# How light can you build a HT steel or Ti bike



## longcat (Apr 24, 2008)

The carbon HT's weigh like 1000g now, how light is it possible to build a Ti/ midrange steel/ top notch steel frame these days?


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## Rody (Sep 10, 2005)

How long do you want it to last?

Seriously, many of the Al and carbon frames have a designed life expectency that is far shorter than the consumer market is cognizant of.

The better question is...

given a riders physiologic needs, riding style, terrain, and performance expectations, what is a realistic weight range for a custom hardtail, in steel and ti, that can be designed, fabricated, and safely enjoyed for years.

Personally, it's never about the weight.

Lightest steel I've made in a small/medium frame...around 3.2 pounds

Lightest Ti I've made...around 2.8

Both with lifetime warranties. Both designed and fabricated for the rider, not the physical characteristics of the end product.

cheers,

rody


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## Walt (Jan 23, 2004)

*Not as light as carbon*

The basics:

Light steel MTB frame = 3.5-4#
Titanium = 1/2# lighter than Steel (at twice the cost)
Carbon or Aluminum = 1/2# lighter than Titanium (with a significantly shorter lifespan, generally)

Total weight savings for an average 175# rider+bike+gear of Carbon/Al over Steel: ~0.5%

If weight is your thing, carbon and aluminum are the way to go. No question. I'd like to think there's more to a good bike than half a pound of weight, though.

-Walt


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## longcat (Apr 24, 2008)

No weight is not my thing actually, It was just a question, since there is all these super steels out there now and the tubes are getting thinner. Reynolds 953 is almost twice as strong as some other varieties,I know you cant shave 50% off the weight for that reason only but you should be able to get some weight off there right? 'The reason I asked is that I was researching steel frames and they, well most of them seemed to weigh in at 2.5kg or so (like Orange p7) but I found a few lighter ones (like Chromag at 1.7kg if im not mistaking), and I just thought there has to be lighter bikes than that.

I'm not the one to say weight matters since the only bike I have is kinda heavy (its even heavier now in the winter with studded tires) and I havent rode any other bike in a few years so I have nothing to relate to.

What exactly do you gain when going from like 13kg to 10 or lower? More control?
I wouldnt mind having an ultralight bike myself since I carry it up stairs every day.


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## Bryguy17 (May 19, 2007)

yeah, I bet you could feasibly make a ti or steel frame at competing weights to carbon ones, but personally, I would also rather sacrifice a half pound of weight for the peace of mind that I can wallup on my bike and it won't break in the foreseeable future.


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## Walt (Jan 23, 2004)

*953 is a joke*

A full 953 frame *might* be 150-200g lighter. I have built a couple of things with 953 and as I recall, for a typical MTB front triangle, you save about 75g. The chainstays are actually heavier, and the seatstays they sell aren't really MTB appropriate.

Here are some thoughts I wrote up at the start of the year:
http://waltworks.blogspot.com/2008/01/reynolds-953-second-attempt.html
http://waltworks.blogspot.com/2008/02/953-project-first-impressions.html

For the price, you're better off just buying Ti.

If you want light *bike*, rather than just a light frame, look at the components - click over the to the weightweenies forum and I'll bet they can take a pound off your bike for <$100 worth of parts.

-Walt



longcat said:


> No weight is not my thing actually, It was just a question, since there is all these super steels out there now and the tubes are getting thinner. Reynolds 953 is almost twice as strong as some other varieties,I know you cant shave 50% off the weight for that reason only but you should be able to get some weight off there right? 'The reason I asked is that I was researching steel frames and they, well most of them seemed to weigh in at 2.5kg or so (like Orange p7) but I found a few lighter ones (like Chromag at 1.7kg if im not mistaking), and I just thought there has to be lighter bikes than that.
> 
> I'm not the one to say weight matters since the only bike I have is kinda heavy (its even heavier now in the winter with studded tires) and I havent rode any other bike in a few years so I have nothing to relate to.
> 
> ...


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## themanmonkey (Nov 1, 2005)

Yea, Walt I've put 953 in the same ballpark as Aermet for those that remember the stuff. Easy to work and cheap are 2 of the main reasons to use steel and 953 has neither of those. I'm interested that folks are really pushing the steel envelope, but 953 is at best half baked right now.

Back to the OP, I've heard of some sub-3 lb. MTB frames were made from True Temper S-3. I built a small road frame in that ballpark a few years back with the stuff, but I don't think it would be up to hard off-road use.


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## pvd (Jan 4, 2006)

People focus too much on weight. Building a good bike is harder to do than build a light bike.


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## longcat (Apr 24, 2008)

Sorry "bike" was a typo, I meant frame of course.

So what would be a good weight for a frame that will be very usable and can handle everyday use without breaking (for a 70kg rider)? Like 1.8-2 kg (steel)? Ti?


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## teamdicky (Jan 12, 2004)

I have a soft spot for this 1545 gram Thylacine Ether:

https://news.thylacinecycles.com/2007/05/or-maybe-it-is/


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## playpunk (Apr 1, 2005)

Now I just need one of those with big wheels and a press in bottom bracket. Yummers.


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## Cheers! (Jun 26, 2006)

My lynksey M230 17" came in at 1315g


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## Hand/of/Midas (Sep 19, 2007)

teamdicky said:


> I have a soft spot for this 1545 gram Thylacine Ether:
> 
> https://news.thylacinecycles.com/2007/05/or-maybe-it-is/


Those are so awesome. Wonder if it could be made to use an integrated headset, like my bmx?


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## longcat (Apr 24, 2008)

Sorry for going a bit OT but how much can I expect to pay for a custom steel bike with, for example Reynolds 853 tubing, no bling, nothing special? Is Ti much more expensive? Im not looking for the lowest bidder since I know people have to eat too but more like a median price so I know how long I have to save up.


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## smudge (Jan 12, 2004)

Hand/of/Midas said:


> Those are so awesome. Wonder if it could be made to use an integrated headset, like my bmx?


It would most likely negate any potential weight savings. I handled a couple of steel head tubes today for use with an upcoming product release...holy nuts were they heavy. My ti sample should be here shortly and I'll be sure to weigh it vs. a standard head tube for future informational purposes.


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## smudge (Jan 12, 2004)

longcat said:


> Is Ti much more expensive?


Yes. Material costs are _*much *_higher.


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## dbohemian (Mar 25, 2007)

smudge said:


> Yes. Material costs are _*much *_higher.


Well, that really depends...Like everything. If the same quality parts are used like paragon dropouts and the like, expensive steel tubing (Life, 853, 953) the costs for titanium will be higher of course but not drastically.

Here is the beef. It is no harder to make a titanium bicycle when you are geared up for it than a steel one. In some ways it's easier. It is an opportunity though for a builder to make a higher profit margin or at least historically because titanium has a gee whiz factor you can charge for. Labor is always a much higher cost than materials and makes up the brunt of any handmade frame price.

I have always been adverse to pricing schemes that for example may have one frame at 1000 dollars and another at 2000 dollars but the price difference in materials is 200 bucks. The way I look at it is that the labor is the same for both frames. Most every framebuilder I know would not do any lesser of a job just because the materials have a price difference so I don't have upcharges for materials. There is the right material for the job and the labor is the labor.

To answer the other questions. Price? So variable, but 1500-2k for a custom MTB seems about what things are going for now. That could swing either way a bit. I think there may even be a lowering of pricing while some of the framebuilders eat each other alive during this hard time, then thing will go back to normal and pricing will increase.

Weight, like it has been said, doesn't really matter....but something that has not been mentioned. By the time you make lets say multiple frames of differing materials that all had the same longevity, stiffness, strength etc they would all begin to weigh similar amounts within a pound or so. Engineers have to make compromises with all materials for the job they are designing around. Yes, a carbon bike could be made lighter than a metal one but then again, it may not have the failure mode one would want in a MTB. It is always a give and take.

Dave Bohm
Bohemian Bicycles
http://www.bohemianbicycles.com


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## pvd (Jan 4, 2006)

dbohemian said:


> I have always been adverse to pricing schemes that for example may have one frame at 1000 dollars and another at 2000 dollars but the price difference in materials is 200 bucks.


That is counter to almost every example of modern mass maufacturing models. A car or motorcycle company will use a $2.00 part instead of a $5.00 part because the $3.00 difference will add $50.00 to the end consumers cost. In addition to this cost view, you also have to look at it from the investment side. That $3.00 additional investment has to generate it's own return. $3.00 invested over 6 months at 30% (yes, 30%) adds about a dollar to the end cost just for tying up the money before payment. So $3.00 costs you $4.00 at the manufacturer. Then you go to the importer, then the wholesaler, then the retailer, then the state and federal taxation... Add to that the additional inventorying costs in the parts distribution stream and you are really talking about a bunch of money.

In case we forget, even if it sounds more like a joke these days...

"General Motors is not in the business of making cars. General Motors is in the business of making money"

Oddly enough, General Motors would be in a much better position right now if it had followed Toyota's lead and made money AND cars.


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## dbohemian (Mar 25, 2007)

PVD, I agree with your overall statement but I am little confused as to the content for a tiny little framebuilder?

I was only referring to this micro, no make that nano business model we call custom steel/ti/aluminum framebuilding. In this model where I takes your money up front, buy materials and then craft a frame from it, I figure labor is where it's at. The way I look at it is why would I give away the frame with lesser materials and make what I need to, to survive on the high end material frames?

I am all about making a living. My frames cost what they cost exclusive of the material used. One is hopefully buying my skill, not metal when they get a frame from me.

I think we are on the same page. I am watching this big 3 thing. It's like that car wreck in a race you know just has to happen, but you can't stop watching... 

Dave Bohm
Bohemian Bicycles


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## dirtdrop (Dec 29, 2003)

I had an 1191g frame once and it flexed so bad. It was sold quite promptly.


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## DWF (Jan 12, 2004)

dbohemian said:


> I am all about making a living. My frames cost what they cost exclusive of the material used. One is hopefully buying my skill, not metal when they get a frame from me.


It's not just the cost of the materials that inflate the price.


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## themanmonkey (Nov 1, 2005)

Getting back to the OP the thing I find interesting about the whole search for light weight has been done again and again, over and over. Who here remembers to popularity of the sub-5 bl. FS frames of the early 90s? How about the Columbus KL and Record frames of the early-80s? Heck look at the French and English builders before and after WWII.

I'm a bit of a weight dork, but I don't expect these things to last very long. One of the all time coolest bikes I've ever had in my possession was a Bill Philbrook made from KL and it as a work of art and scary light. The new materials really are coming along and soon we may see reliable sub-3 lb. steel frames, but not for a while I believe.


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## pvd (Jan 4, 2006)

dbohemian said:


> My frames cost what they cost exclusive of the material used.


That is certianly the case with your bikes. They aren't my thing, but I love looking at them. They are truely jewlery at the scale of bicycles. Can't wait to see a few more.


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## pvd (Jan 4, 2006)

DWF-

It looks like your site is down.


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## dbohemian (Mar 25, 2007)

Agreed with the great DFW 100%. I guess what I should clarify is that I don't "lower" the price based on a tube set being cheaper.  

Brandon, I have some of that KL in stock. Wasn't record .3 wall? Anyways, light is nothing new of course. I think once people have mastered a certain material they naturally begin to investigate how light they can get something until failures outweigh any perceived benefit to being lighter.

That is a beautifully done frame BTW. I like everything. The drops are especially nice.

Dave Bohm
Bohemian


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## dbohemian (Mar 25, 2007)

pvd said:


> DWF-
> 
> It looks like your site is down.


Working perfectly for me as of 10 seconds ago?

Dave B


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## DWF (Jan 12, 2004)

pvd said:


> DWF-
> 
> It looks like your site is down.


Could be, it's getting some work done on it today.


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## DWF (Jan 12, 2004)

themanmonkey said:


> Getting back to the OP the thing I find interesting about the whole search for light weight has been done again and again, over and over. Who here remembers to popularity of the sub-5 bl. FS frames of the early 90s? How about the Columbus KL and Record frames of the early-80s? Heck look at the French and English builders before and after WWII.
> 
> I'm a bit of a weight dork, but I don't expect these things to last very long. One of the all time coolest bikes I've ever had in my possession was a Bill Philbrook made from KL and it as a work of art and scary light. The new materials really are coming along and soon we may see reliable sub-3 lb. steel frames, but not for a while I believe.


That is a cool bike. Sometimes less is more. Like the dropouts too but they don't "fit" the style of the bike.


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## DWF (Jan 12, 2004)

dbohemian said:


> Agreed with the great DFW 100%. I guess what I should clarify is that I don't "lower" the price based on a tube set being cheaper.
> 
> Brandon, I have some of that KL in stock. Wasn't record .3 wall? Anyways, light is nothing new of course. I think once people have mastered a certain material they naturally begin to investigate how light they can get something until failures outweigh any perceived benefit to being lighter.
> 
> ...


Lightest I did was 2.8 for a steel road frame. Too light, IMO. Extra 1/4 -1/2 pound can make all the difference in the world. Didn't like building sub 4 pound frames for MTBs, it's inevitable that someone is going to put a longer than design fork on it or AM an XC race bike, etc. A well made four pound steel MTB frame is going to be plenty burly for most folks and still have those delicious steel ride qualities. 4 is the magic number for bike frames in all materials.


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## smudge (Jan 12, 2004)

dbohemian said:


> Well, that really depends...Like everything. If the same quality parts are used like paragon dropouts and the like, expensive steel tubing (Life, 853, 953) the costs for titanium will be higher of course but not drastically.
> 
> Here is the beef. It is no harder to make a titanium bicycle when you are geared up for it than a steel one. In some ways it's easier. It is an opportunity though for a builder to make a higher profit margin or at least historically because titanium has a gee whiz factor you can charge for. Labor is always a much higher cost than materials and makes up the brunt of any handmade frame price.
> 
> ...


Dave, rather than write up a point by point argument (which I just deleted because I realized how boring it was) I'll just say that I disagree with your first statement (cost of materials). If you want to compare high end steel to SG ti, the ti is still more expensive, often by a long shot. Compare it to the butted tubing available to small builders and even to the seemingly non-existent 6/4 butted Reynolds ti and the costs runaway quickly.

Anyone carving lugs or filing fillets knows how much labor is required and I respect the amount of time those guys put into it. Welding ti versus steel isn't necessarily the same process and as is the case with many builders, ti can be much more time consuming in every step of the building process. Stating that they're the same and that profit margins are higher because of the ti cachet is doing a disservice to the builders. My understanding is that one prominent builder can build a steel bike in 4 hours but needs 16 for a ti one.


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## dbohemian (Mar 25, 2007)

I respect your opinion. All I can really gauge things on is how I do them.

just an example. If one wants to do the very best job they can TIG welding high end steels vs. Titanium. I for one would take exactly the same cleaning steps, backpurge, etc as I would with Titanium (I did build some ti bikes in the past, I realized there were better than I and stuck with steel)

I agree one could skip those steps which of course is not possible with Ti but if everything is followed then they will take a similar amount of time to produce. Granted I am talking high end one at a time builders, not production.

I mean no dis-service. I think if you ask most Ti guys and gals they will tell you that Ti has a higher profit margin and I think that is great!

Dave Bohm
Bohemian


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## smudge (Jan 12, 2004)

dbohemian said:


> I respect your opinion. All I can really gauge things on is how I do them.
> 
> just an example. If one wants to do the very best job they can TIG welding high end steels vs. Titanium. I for one would take exactly the same cleaning steps, backpurge, etc as I would with Titanium (I did build some ti bikes in the past, I realized there were better than I and stuck with steel)
> 
> ...


I understand what you're saying and am not trying to stoke anything but with the disclaimer that I know how a lot of guys around here do it...

I do all my own seat and chain stay bending, many steel builders have the luxury of choices when it comes to buying stays.

Many, but not all, ti builders run multiple weld passes which not only adds significant time to the weld process, argon consumption goes up. I'm not aware of any steel builders who admit to multiple passes.

I know a lot of subtle information gets lost during internet communication. I'll come out and say that you're one of the guys for whom I have a great deal of respect with regards to ability, vision and willingness to present a well thought out and unemotional opinion on the internet. :rockon:


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## dbohemian (Mar 25, 2007)

Thanks man,

Some serious work goes into most of the Ti frames I have seen and your right, the choices that steel builders just usually don't exist for the Ti guys so huge props to doing that stuff.

To add some MTB content here. Here is a small preview of a 29nr I am finishing up. It will be complete and then I want to get some really good shots of it. The paint scheme is based off of a five lined skink....























































Every lug, reinforcement etc. was turned on my lathe. I tapered each one to distribute stress and forged the tips over so it is kind of a half lug/half fillet braze joint.

To keep things on topic. It weighs 4.4 Lbs

Dave Bohm
Bohemian Bicycles

P.S. there is a little more at my flickr page.

https://www.flickr.com/photos/bohemian_bicycles/?saved=1


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## byknuts (Aug 9, 2008)

Dave... you are absolutely batshit with those details 
(in a good way... a very VERY goooood way)


I just want to have it in my hands to stare at it. 
Pure art.
(words kind of failing me here... sorry!)


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## SuspectDevice (Apr 12, 2004)

DWF said:


> 4 is the magic number for bike frames in all materials.


Alumo-phobe!

2 pounds is as light as we are able to design an aluminum road racing frame. IE, one designed to last indefinitely under pro-level use, and have the proper comfort and handling characteristics.

2.8 pounds is the sweetspot for a well designed aluminum xc race/trail frame.

I got the weights nice and low without compromisg anything on those bikes.

The lightest steel xc frames I've been able to stick together are right at 3.75lbs... I would never want to go lighter than that for a steel mtb frame, especially with a rear end that holds up to discs, and a front end that works with a 4"+ fork. It is, of course possible to build a super duper 3pound or sub 3 pound steel frame, but um... Why when I can sell someone an Aluminum frame at the weight that will likely ride better?

I wouldn't ever want to go below three pounds or really, much above 3pounds for a steel road frame either. So many near-perfect steel tubes out there to build with makes it easy...

The frame is, literally, the heart of the bike. Anything too far out of the ordinary safe-zone, weight wise is just so phenomenally gimmicky, IMO. Light bikes come from all the parts being light, not just a super-light frame.


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## Thylacine (Feb 29, 2004)

I think an issue here that hasn't directly been discussed, is if you have your own little frame company, do you want to be known as the guy that makes the lightest bikes in the world that also ride like complete crap?

For me there's a chasm of difference between a frame made for racing and a frame made for resting against a wall while sipping a decaf soy latte. I want racing credentials because that pushes Design, which is my key interest. It tells you exactly where the edge of the cliff is.

The Ether that Dicky posted was 2 years or R&D and prototyping (That's an early proto). The guy testing it was Erin Francis, one of the top 10 U23's in Australia. He broke a stack of them, but the value here is that I know where the bottom really is, and I think that's valuable even just for the sake of knowing what's _actually_ possible, rather than just the theory.

Any lighter and it would break or ride very badly.

Any extra weight is just for longevity and/or riders who aren't 69kgs.

Personally I don't care in the slightest about frame weight, but the market does, and so does my curiosity to find out what's possible.


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## Thylacine (Feb 29, 2004)

dbohemian said:


> I am all about making a living. My frames cost what they cost exclusive of the material used. One is hopefully buying my skill, not metal when they get a frame from me.


That's exactly it, Dave.

But they're also buying your ability to reinvest in your business. That means having capital to grow it.

I probably shouldn't mention also that people love paying for the intangible, which more often than not means paying a lot of money for a companies advertising, sponsorships, and precieved or real image. It costs a lot to develop and maintain that.

The prime example is Oakley sunglasses, where in terms of pure costs, the glasses themselves are a very minor part of that.

How successful would they have been if they sold for 50 bucks rather than 200? The production cost on those things is in the vicinity of 7 bucks.


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## Vlad (Feb 7, 2004)

Dave, the frame that you posted is b!tchin'. How does lugged construction hold up for hard off-road riding? I keep fantasizing about a rigid 26" single speed, but I'm not sure what I want yet (and I got laid off yesterday, so I'm pinching pennies).

--Antoine


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## dbohemian (Mar 25, 2007)

Vlad said:


> How does lugged construction hold up for hard off-road riding? I keep fantasizing about a rigid 26" single speed, but I'm not sure what I want yet (and I got laid off yesterday, so I'm pinching pennies).
> 
> --Antoine


Sorry about your job man :cryin: Hopefully you will get something better will come your way.

As we all know, TIG welding, Fillet Brazing, heck even bonding can make a very durable structure. Lugs, although an unknown joining method for MTB nowadays can make a frame that is every bit as durable as the other methods.

Keith Bontrager did some tests back in the day and found that I believe fillet brazing was the most durable as far as fatigue was concerned. Paramount did some tests and found lugs were the most fatigue resistant. I don't think this has been definitively answered.

Lugs are dead for many reasons. They don't fit the majority of MTB designs (which is why I custom fabricated these) you can't change up design or tubing on the fly. They cost as much as the tubing itself sometimes. A specific skillset is needed to put them together that is essentially dead, they take a lot more finishing both before construction and afterwards along with paint. They can weigh more (not always) than purely welded frame. Lugged bikes are expensive. But durable they are...Sweet looking too IMHO.

Dave Bohm
Bohemian Bicycles


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## jmoote (Aug 31, 2007)

pvd said:


> People focus too much on weight. Building a good bike is harder to do than build a light bike.


Building a good and light bike even harder yet. All the more reason to try, as far as I'm concerned.

As has been said the frame is not really the place to save 100g though. There are reasonable weights for frames of all materials. I strongly agree with SuspectDevice's numbers for the various materials and uses. My steel XC frame @ about 3.75 lbs gives precisely the ride quality that you'd expect from a great steel frame.


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## Vlad (Feb 7, 2004)

dbohemian said:


> Sorry about your job man :cryin: Hopefully you will get something better will come your way.
> 
> As we all know, TIG welding, Fillet Brazing, heck even bonding can make a very durable structure. Lugs, although an unknown joining method for MTB nowadays can make a frame that is every bit as durable as the other methods.
> 
> ...


Thanks!

And thank you for the info re. lugs and whatnot. So many cool bikes to ogle.....


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## BeatAFool (Jan 14, 2008)

How light can a steel frame be??? Light enough........... I've never weighed any of my bikes, I have no clue what any of them weigh but if I had to guess I'd say............ "light enough" or "not heavy"


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## DWF (Jan 12, 2004)

SuspectDevice said:


> Alumo-phobe!
> 
> 2 pounds is as light as we are able to design an aluminum road racing frame. IE, one designed to last indefinitely under pro-level use, and have the proper comfort and handling characteristics.
> 
> ...


Suspect, I'm sorry, but I'm gonna have to go all Missouri on you and say "show me" on the 900-gram aluminum frame tested to demonstrate an indefinite life under a capable rider.


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## dbohemian (Mar 25, 2007)

Does any frame last indefinitely? That is excepting my flying pigeon










Dave Bohm


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## jmoote (Aug 31, 2007)

Exactly - every frame has a lifespan. It's all about making it reasonable. If you want a disposable frame for racing, any builder can make you a 1 season frame, 3 season frame, or whatever. For more general use, it seems wise to make the lifespan in the range of 5-10 years. Any longer than that and you're unlikely to be riding the same frame anyway as things change (different riding style at the time, new technologies - BB standards, etc.)


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## SuspectDevice (Apr 12, 2004)

DWF said:


> Suspect, I'm sorry, but I'm gonna have to go all Missouri on you and say "show me" on the 900-gram aluminum frame tested to demonstrate an indefinite life under a capable rider.


I should have been more speecific, 2.2 pounds IE a thousand grams. Riding A 900 gram frame would make me very, very nervous...


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## themanmonkey (Nov 1, 2005)

One of the things I was taught years ago was all frames break, the trick is figuring out how it will break. Predictable failure mode is a basic engineering design concept I understand (actual engineers please correct me if I'm wrong) and this is part of my personal thought process. The idea can be illustrated by thinking about wanting a part to bend or crack instead of shear, or have at ST/BB joint fail instead of DT/HT joint. It's not an 'if' it's a 'when' and most builders and designers don't think of it in such a way.

A good real world example is forks. Back in the day ('80s and before) you rarely ever saw a properly built fork fail first. Instead you saw lots of frames with buckled TTs and DTs. Rarely did you see really bad injuries. Lots of folks complained that forks were too beefy and could be lighter, also that the most expensive part of the bike (i.e. frame) was destroyed and a cheap part (i.e. fork) was just fine. When carbon forks started becoming popular we saw a lot of failures at the fork end of things and also a large increase in bad injuries. It didn't take long for the fork designers to start beefing things up and making stronger parts.

I've broken tons of "unbreakable" bikes and parts and I'm not big, heavy, or that aggressive a rider. I am willing to ride trials ona CX bike and take road bikes off-road. If a bike stands up to serious riding and abuse that is a bonus, but it shouldn't be a given. Oh, and one other thing. Overbuild should never be an excuse for poor design which is something we see way too much of in the real world.

Build it, Ride it, Break it.


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## TimWoo (Oct 6, 2007)

dbohemian said:


> Thanks man,
> 
> 
> 
> ...


offtopic. Just want to say that's absolutely beautiful.


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## coconinocycles (Sep 23, 2006)

i never weigh my stuff, but one of my customers just did. disclaimer: small bike, small customer = 3.7lbs. steve.


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## jmoote (Aug 31, 2007)

Just curious, Steve - what do you tell a customer who wants some idea of what the weight will be on their prospective frame? Do you tell them you don't know, and they can take or leave that, or do you give them a stab in the dark estimate?


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## DWF (Jan 12, 2004)

jmoote said:


> Just curious, Steve - what do you tell a customer who wants some idea of what the weight will be on their prospective frame?


"You gonna' weigh it or ride it?"


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## coconinocycles (Sep 23, 2006)

jmoote said:


> Just curious, Steve - what do you tell a customer who wants some idea of what the weight will be on their prospective frame? Do you tell them you don't know, and they can take or leave that?


 yep. i pick out the appropriate tubing and build it. = happy customer!


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## jmoote (Aug 31, 2007)

Sounds good


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## Vlad (Feb 7, 2004)

I've four bikes in rotation--BMX, MTB, track, and 26/24 trials/urban nonsense, and I don't know how much any of them weigh. I can estimate, but I really don't care. They feel just right.


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## perttime (Aug 26, 2005)

*What about the rider?*

When doing a custom frame (and maybe fork too), surely the 60kg and the 100kg guys get different tubes and/or designs for similar uses.


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## coconinocycles (Sep 23, 2006)

perttime said:


> *What about the rider?*
> 
> When doing a custom frame (and maybe fork too), surely the 60kg and the 100kg guys get different tubes and/or designs for similar uses.


ya, youbetcha! that's part of the deal with a good custom builder. weight, body type, age, intended use, many factors.........steve.


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## perttime (Aug 26, 2005)

coconinocycles said:


> ya, youbetcha! that's part of the deal with a good custom builder. weight, body type, age, intended use, many factors.........steve.


Exactly as I thought.

So, there's no simple answer to the question "How light can you build a HT steel or Ti bike", before you know quite a lot about the rider and the intended use.


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## themanmonkey (Nov 1, 2005)

perttime said:


> Exactly as I thought.
> 
> So, there's no simple answer to the question "How light can you build a HT steel or Ti bike", before you know quite a lot about the rider and the intended use.


Uh, no. It is quite simple because you become limited by the materials. Sure you could try and build a 2-lb steel frame for you 50 lb kid, but good luck finding material to do it. And even at that if you scale it up you've got a 6-lb frame for a 150 lb rider. There really is a small window that a good build and quality materials wall into.


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## perttime (Aug 26, 2005)

I'll put it differently: looks like it is possible to build a steel XC race frame for an adult height person close to 1.5kg. Right? I don't think it would be a quite that feasible to make an everyday steel trailbike frame for a 100kg guy at that weight.


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## themanmonkey (Nov 1, 2005)

Go back and read post #2. 3.3 lbs (1.5 kg) is light, but not crazy light. That is the bottom of the narrow range I talked about, 4.5 lbs (2 kg) being the upper range. The magic lower window for steel has usually been 1.3 kg (<3 lbs).


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## coconinocycles (Sep 23, 2006)

themanmonkey said:


> Uh, no. It is quite simple because you become limited by the materials. .


 yeah, one of the things i think about is pure durabilty - no necessicarily breakage, but denting and scaring too. i assume that since i build mostly MTN bikes that they are gonna see rocks, roots, get thrown around. i built quite a few 7/4/7 bikes, but they just got pinger dents and scars from falling {esp the seatsyays} 8/5/8 and 9/6/9 are just less "denty" it may be just me, but true temper seems less "denty" for some reason.  just thoery.......but it sure seems so.....fwiw, 4-4.5lbs seems like a sweet spot for "average" joes........steve.


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## jmoote (Aug 31, 2007)

coconinocycles said:


> fwiw, 4-4.5lbs seems like a sweet spot for "average" joes........steve.


I assume the "average" cross country racer doesn't fit into that category of "average" joes? I don't see a problem with a 4-4.5 lb frame for just riding around, but for a steel race bike I would expect under 4 lbs - not just to have a light bike, but to handle the way you want it to. I would guess my (mostly) 0.7/0.4/0.7 OX Platinum 29er frame is around 3.6 lbs though I've never had the frame only on the scale (amazing for someone like me, but it was half built up when I got it...)


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## coconinocycles (Sep 23, 2006)

jmoote said:


> I assume the "average" cross country racer doesn't fit into that category of "average" joes? I don't see a problem with a 4-4.5 lb frame for just riding around, but for a steel race bike I would expect under 4 lbs - not just to have a light bike, but to handle the way you want it to. I would guess my (mostly) 0.7/0.4/0.7 OX Platinum 29er frame is around 3.6 lbs though I've never had the frame only on the scale (amazing for someone like me, but it was half built up when I got it...)


disclaimer: i don't build race bikes. i do build bikes for "just riding around" be it on local trails, to work, or the length of the pan-american. {although, heck - race them if you want, i raced the heck outta mine, with great results! so do many others...} steve.


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## jmoote (Aug 31, 2007)

Thanks, that clarifies lots Steve. The way you put it is perfect - race it if you want, but it's not a race bike. I'm glad you're honest enough to say so, as I feel many builders would not be. I'm lucky enough to have a builder who enjoys building race bikes, and that's cool too.


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## themanmonkey (Nov 1, 2005)

Weight does not a race bike make.


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## Walt (Jan 23, 2004)

*"Race" bikes*

This might start to sound like a rant at some point, but please don't take it personally.

I love the idea that there is some fundamental difference between a "race" bike and a "trail" bike. As if somehow a race bike needs to handle differently or be built in some specific magical way that will make it raceworthy.

Here's what I know - I've raced as a pro here in Colorado (a really crappy one, but then again I don't do any training) for almost a decade. In that time I've had an awful lot of bikes, some of them advertised as "race specific geometry" high-speed podium finishers, others as just regular old mountain bikes, and everything in between. For a good portion of that time, I've built my own bikes and raced them. Here's what I've learned:

-Race _geometry_ is actually the opposite of what most people think. You do not want a bike with a low trail number for racing, at least in the Rockies, because by the time you get to the downhill (and the bike handling) you are way too tired to be fighting to keep the bike going in a straight line at speed. Predictability and stability are key for race bikes, even if that means sacrificing some low-speed nimbleness. You're always faster if you don't crash and aren't afraid to let her rip on the straight stuff. This goes double for enduro racing, where you're going to be completely wasted both mentally and physically by the end of the race.

-Frame weight is virtually unnoticeable. Sure, an extra pound of weight won't make you faster, but it also isn't going to change where you finish unless you're within a few seconds of the next guy or gal. A pound of frame, for an average guy, is 1/2 of 1% of the total weight of bike/rider/gear. Do you want to ride a heavy bike? No, not really. But a frame that handles predictably and fits well is WAY more important than a few hundred grams of weight. The frame is the last place to try to save weight, IMO. Most other components merely need to be durable - as long as your seatpost doesn't break, it doesn't matter, so get the lightest one you can. But if you have a frame that fits or handles poorly, you're not going to be fast no matter how light it is.

-Unless you're getting your frames for free, or you're independently wealthy, a durable frame is a better choice than an ultralight one. I think I broke 2 different Homegrown frames when I rode for Schwinn - and I never could have afforded replacements if they weren't free. There's a reason the really fancy bikes you see at a race are mostly ridden by Sport 45-49 guys who are tax attorneys by day. Look at the pro field and you'll see some fancy bikes ridden by the top guys (who are increasingly rare these days) and then a whole bunch of *random crap* ridden by the rest, most of whom are really, really fast. These guys are well aware that they could buy a "nicer" bike, but they also know that it won't make them any faster, _so they save their money for entering races and/or not working as much so that they'll have more time to train._ If you aren't rich, and you're buying a new bike every year you're being penny wise and pound foolish, as far as race results go. _Less bike and more training will make a huge difference, so save your $5k (assuming you like your current bike), take some unpaid vacation days to train, and hire a coach while you're at it._

Bottom line, I guess, is that for me, a bike that is a good bike for riding trails with your friends is *also* a good bike for racing. There is no such thing as a "race" bike in my book. Most of us "race" our buddies up and down certain trail sections on pretty much every ride, and try to go as fast as we safely can all the time - hence the bike is really doing the same duty it would in a race. Ultralite disposable frames (how many Trek 9.9s are still around, only about 5 years after being the most popular race bike on the planet?) are a poor investment if speed is what you're after - invest your money and time in your fitness and skills, not fancier equipment.

-Walt



jmoote said:


> Thanks, that clarifies lots Steve. The way you put it is perfect - race it if you want, but it's not a race bike. I'm glad you're honest enough to say so, as I feel many builders would not be. I'm lucky enough to have a builder who enjoys building race bikes, and that's cool too.


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## jmoote (Aug 31, 2007)

Walt, I do not disagree with a single thing you said, but it's all in how one applies these ideas:

You say a bike with a low trail figure does not make a good race bike _in the rockies_. We don't all live in CO. Race geometry is something different everywhere you go. For twisty flat stuff low trail numbers are exactly what you want.

I also agree that frame weight is hugely secondary to how a frame handles. Are you disagreeing that for some folks a lighter whippier frame is not their idea of better handling? I like a frame that has some spring to it, but is stiff enough that it is still predictable when descending.

I also agree that a less expensive frame that is durable is the better investment. We're in a forum where we are largely talking custom frames, however. I don't feel it's a stretch to say that you can make a sub 4-lb steel XC bike that will also last as long as you could possibly want it to. I don't get my frames for free, but if it breaks and I didn't do something stupid to cause that, the builder will stand behind his work. If I did do something stupid, he'll still fix it but of course I will pay for it since it was my fault.


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## coconinocycles (Sep 23, 2006)

*warning: straight talk.*

OK - remember, i sell custom steel bikes for a living, so take that into account when you read this. sooo.... you want a 3lb ish race frame? well, anything that weighs that much and gets ridden hard {you're RACING, right?} is gonna bust. so, rather then wait a long time and pay a bunch of $$ for a custom steel frame, just buy last year's closeout scam-dium frame and have at it! when it busts, try to warrenty it, or if you get tired of it, give it to a kid or something. a custom steel frame is an investment meant to last a long time. there are probally features built into it {like say, a seat tube sleeve} which, while making it slightly heavier, will make it last longer. "it's not the fastest rider that wins the down hill, it's the one who gets there 1st" - Greg Herbold. "a heavier bike is faster then a broken one" - Steve Garro. "shred it, don't pet it" Brockstar. i know this is OT as per original question, but there you go. i'm pretty much 100% with walt's last post as well. steve.


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## DWF (Jan 12, 2004)

coconinocycles said:


> OK - remember, i sell custom steel bikes for a living, so take that into account when you read this. sooo.... you want a 3lb ish race frame? well, anything that weighs that much and gets ridden hard {you're RACING, right?} is gonna bust. so, rather then wait a long time and pay a bunch of $$ for a custom steel frame, just buy last year's closeout scam-dium frame and have at it! when it busts, try to warrenty it, or if you get tired of it, give it to a kid or something. a custom steel frame is an investment meant to last a long time. there are probally features built into it {like say, a seat tube sleeve} which, while making it slightly heavier, will make it last longer. "it's not the fastest rider that wins the down hill, it's the one who gets there 1st" - Greg Herbold. "a heavier bike is faster then a broken one" - Steve Garro. "shred it, don't pet it" Brockstar. i know this is OT as per original question, but there you go. i'm pretty much 100% with walt's last post as well. steve.


It's a trifecta. I agree with WW too. Here's my problem with superlight bikes/frames regardless of the material they're made out of: I know a little something about materials and I know that anything that breaks in front of the BB shell is potentially the end of your life as you know it. Head tubes, top tubes, down tubes, forks, stems, handlebars, or front wheel failure can end you. The last thing I want going through my mind entering a rock garden as speed is whether or not my bike is up to it.


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## Walt (Jan 23, 2004)

*Clarifications*

J -

Agreed that not everyone lives on the West Coast or in the Rockies. And geometry has to reflect local conditions.

Frame flex isn't related all that strongly to weight, though. I can build a heavy flexy frame, or a light stiff one. That's a tube diameter question, not a weight/tube wall thickness issue.

Finally, a bike goes through MORE abuse in most cases during a race than it ever goes through on ordinary rides - people (myself included) do absolutely idiotic things, crash more, and ride lines they never otherwise would during a race. Of course, we spend a lot more time riding than we do racing, but I'd still argue that a "race" bike needs to be at least as durable as a bike that will never be raced at all.

-Walt



jmoote said:


> Walt, I do not disagree with a single thing you said, but it's all in how one applies these ideas:
> 
> You say a bike with a low trail figure does not make a good race bike _in the rockies_. We don't all live in CO. Race geometry is something different everywhere you go. For twisty flat stuff low trail numbers are exactly what you want.
> 
> ...


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## Thylacine (Feb 29, 2004)

I don't think there is a builder alive that doesn't agree that good design (building the appropriate bike for the particular rider) and longevity (we're selling privateer, investment bikes) are essentially what custom bike building is all about.

I predict within 18 months there will be a slew of people coming back to - or considering custom steel or Ti for the first time - because they've discovered that their 1200g carbon hardtail has about the same trail-worthiness as papier mache.


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## Flystagg (Nov 14, 2006)

This discussion sure has gone all over the place, from bashing titanium, to bashing lightweight steel to bashing lightweight bikes in general. I admit, I'm not very well versed in steel, (I have 4 lb steel frame that I enjoy), but to my bike knowledge I've seen lots reliable of sub 3lb titanium bikes. The merlin xlm comes to mind right off the bat at about 1300 grams, and I know guys winning xc and downhill races on 10 year old xlms today. So to re-ask the op question what would be the cost of a custom reliable 13-1450 gram titanium frame?


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## SuspectDevice (Apr 12, 2004)

Flystagg said:


> . So to re-ask the op question what would be the cost of a custom reliable 13-1450 gram titanium frame?


If you could afford one, you wouldn't need to know.


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## Thylacine (Feb 29, 2004)

Clearly you haven't seen DH racing for a couple of decades.

Winning a DH on a Merlin?


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## longcat (Apr 24, 2008)

Which frame out of these would you guys recommend? 

Chromag sakura @ 3.75lb (which is under the 4-limit)
or Chromag Samurai @ 4.75lb? Will there be any noticeable difference between those 2 frames? Thinking about if the heavier one will be a worse ride, or overbuilt for my weight. My weight is around 70kg. I like the looks of the Samurai better but I dont know if i should get the lighter one instead because its lighter and may be a softer/more comfortable ride.


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## TortugaTonta (Jun 14, 2004)

The interesting thing is that from years of building steel frames everyone has a good idea of how to build a reasonably light and good riding steel frame, you look at the alloy, the wall thickness and butts and you know what tubes to pull off the shelf.

With carbon, people sit in front of a computer and simulate loads to try to get an idea of how to make the strongest and lightest frame. Some would argue that this is a better way of designing a frame than just going by years of experience building steel. But in reality the computer model tests riding the bike under perfect conditions and here is my example to show this. A good friend of mine is a mechanic for a large national road team, by june this year they had broken 12 carbon frames, yes 12. Most failures were believed to be caused by road debris. Situations like entering a turn while braking and having a pebble kick up from the front tire and hit the down tube which would cause the down tube to crack and fail. Yes the computer model said the wall thickness should be sufficant to handle the load but it seems they dont take stuff like pebbles into consideration. He also told me his team was not alone and other teams were having similar problems.

I have a 2004 Madone that I love, rides great, I was hit by a car on that bike and had to replace the fork but the frame still rides great, But I do not think I will buy another carbon road bike because I really think they are trying to build them too light now.It is just not safe.


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## SuspectDevice (Apr 12, 2004)

longcat said:


> Which frame out of these would you guys recommend?
> 
> Chromag sakura @ 3.75lb (which is under the 4-limit)
> or Chromag Samurai @ 4.75lb? Will there be any noticeable difference between those 2 frames? Thinking about if the heavier one will be a worse ride, or overbuilt for my weight. My weight is around 70kg. I like the looks of the Samurai better but I dont know if i should get the lighter one instead because its lighter and may be a softer/more comfortable ride.


What are you going to do with the bike? There will be super huge differences between them, as they have completelely different tubesets and machine parts and intended use.

We build a bike with the same dropouts and most of the same tubes as the Sakura (the Horror Taxi. I sell it as xc race/trail frame. The Samauri is something you can and should ride far more agressively, IE a pure trail bike that you could race 4x on.

The Sakura and Samuri are very different bikes, for different uses.


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## dbohemian (Mar 25, 2007)

TortugaTonta said:


> A good friend of mine is a mechanic for a large national road team, by june this year they had broken 12 carbon frames.


Good post. What I think a lot of people don't understand is that everything is a compromise in designing. Even with wonder materials to obtain the ultimate in lightweight one must have a shorter lifespan/reduced crash resistance/toughness.

In motorsports for instance it is a given that components do not last forever. An extreme example of this is top-fuel dragsters. they only go a 1/4 mile before an engine overhaul. All other forms of racing have replacement schedules and even considering this there are failures. Often it is the more reliable car/motorcycle that wins over the fastest one, that is if the fastest one does not complete a race.

It has become the same with bicycling to some extent. I don't see a big issue with a professional rider trading out a bicycle a few times a year. I don't think that your average joe who chunks down a lot of their hard earned money really understands the limited lifespan of some of these frames/components.

Dave Bohm
Bohemian Bicycles


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## Thylacine (Feb 29, 2004)

dbohemian said:


> I don't think that your average joe who chunks down a lot of their hard earned money really understands the limited lifespan of some of these frames/components.


Well if you look at the fine print on most of the warranties, they're "void if raced" anyway, so if they don't understand the concept, it won't be long before they do!

We shouldn't forget too, that some risk manager has already done the sums so the risk of failure of these 900g road frames is offset by their low production cost and high margins.

It just pains me that people will still pay the same amount of money for a high end stock road frame rather than a similar custom frame, and a large chunk of that reasoning is the warranty (or percieved warranty).


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## hoovermd (Dec 22, 2007)

Now granted I'm no world class racer but... the difference between my "race" bike and my "day" bike is simply the rim/tire combo...

Durability is key... Here is one of my favorite local Cyclocross challenges.
In this photo I pinch flatted the front.
On this particular downhill I've passed many an MTBer, OTB'd a few times. Even busted a carbon fiber handlebar but I've never damaged my frame.


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## anthonyinhove (Nov 3, 2007)

Can you guys please explain a bit more the concepts you’re talking about?

The OP asked about ti as well as steel. Am I correct in thinking that ti has a different limiting factor? i.e., that as ti gets very light, it will become too flexy for XC before it will fail, so the limiting factor is flex. Whereas the limiting factor for steel is almost equal between flex and durability? And the limiting factor for aluminium is purely durability. i.e., aluminium is still stiffer than you might want, even when it has become marginal for strength - the opposite of titanium?

And what does durability mean? My understanding was steel doesn’t deteriorate much with age. So if it can withstand an impact force of X once, can it carry on withstanding further impacts of X over many years? Some of the talk about durability here suggests that a frame might withstand X once, but with some damage - and that the damage builds up until after maybe 100 impacts of X over maybe a year, the frame breaks, is that right? And is it the tube that fails or the weld?


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## dbohemian (Mar 25, 2007)

Materials science gets pretty complicated. It is not always obvious how something works.

This is a great into to how materials behave. Scot Nicol's metallury for cyclist article

http://www.ibiscycles.com/tech/materials_101/

and if you need a T-shirt with the opening tidbit of barbarian wisdom on it. They are for sale here:

http://www.bohemianbicycles.com/tchotchke.html

Hope that helps.

Dave Bohm
Bohemain Bicycles
http://www.bohemianbicycles.com


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## themanmonkey (Nov 1, 2005)

One other thing to remember as folks continue to slag on CF as a building material. CF is used for light weight in the bicycle world and can be just as strong as as the metals we're discussing. If you built a 3 lb CF frame you would have something just as strong, if not stronger than steel or ti.


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## TortugaTonta (Jun 14, 2004)

here is a good read ....

http://www.amazon.com/Why-Things-Br...=sr_1_1?ie=UTF8&s=books&qid=1229435826&sr=1-1

Another thing I would like to point out is this.

The difference in weight of ti, steel and aluminum tubes is minor. If you hold 3 down tubes in your hands you really can't tell a difference. The difference can be felt in the head tube, bottom bracket, drop outs and brake mounts. A .049 thick steel drop out would probably be as strong as an conventional aluminum one, but you would not have enough material to interface with the axel or thread in a rear derailleur. So basically you need to have a minimum amount of material for mechanical interface at the bb, ht and drop out reguardless of overall strength and that is where you feel the difference in weight.

Where you can't tell the difference between 3 down tubes you will feel a difference between the three drop outs, the steel ones feeling twice as heavy as the aluminum and 50% heavier than the ti.

Another thing I would like to point out for those with little experience. You really can't believe the difference in "toughness" between regular 4130 and say reynolds 853 and other air hardening alloys. A crappy home depot hole saw will mitre 4130 with ease, but try one on some 853 and watch the teeth fly  those tubes are amazingly tough. But also very difficult to work with when you are trying to tig a down tube onto a bottom bracket where the 853 has less than half the wall thickness of the bb shell and you vaporize the 853 long before the bb shell goes molten


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## anthonyinhove (Nov 3, 2007)

themanmonkey said:


> One other thing to remember as folks continue to slag on CF as a building material. CF is used for light weight in the bicycle world and can be just as strong as as the metals we're discussing. If you built a 3 lb CF frame you would have something just as strong, if not stronger than steel or ti.


But isn't the suggestion that CF fatigues? And therefore you need to build frames with a greater contingency margin of strength if you want them to last ten years than if you are content for them to last just one? Whereas steel fatigues very little, so will survive a long life if it's strong enough to survive at all?


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## dbohemian (Mar 25, 2007)

composites do not fatigue in the way that metals do. Often it is for other reasons. 

Composites theoretically should have equal to greater fatigue resistance than steel or titanium. Other things happen like degredation of the epoxy over time, things like that. These are improving constantly so what is an issue today, may not be an issue tomorrow.

The real issue and Don Ferris mentioned it before. All frames basically turn out to weigh a similar amount if they are optimized for the same levels of durability. CF frames are often much lighter, because lighter sells and they sacrifice some durability for it. 

Really, they are not typically as resistance to damage that leads to an eventual failure and then of course that failure looks terrible. For instance. A crash leads to a small localized failure, this propagates over time and then fails. To the owner it seems that it "just happened" Steel on the other hand would most likely just have a dent you could ride that way forever.

This is complicated stuff. People often try and simplify it and that just doesn't really tell the whole story.

Dave Bohm
Bohemian Bicycles


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## themanmonkey (Nov 1, 2005)

anthonyinhove said:


> But isn't the suggestion that CF fatigues? And therefore you need to build frames with a greater contingency margin of strength if you want them to last ten years than if you are content for them to last just one? Whereas steel fatigues very little, so will survive a long life if it's strong enough to survive at all?


No. There is so much hype, in both good and bad directions, in the bike industry about CF and composites that I don't look at the bike industry for info. Start reading about CF in aeronautical and military applications. Even the automotive world. Look at the stresses a F-1 racecar body undergoes in just one race. There are more and higher fatigue cycles in one race than a bicycle will see in 3 lifetimes.

Steel has a ton of downsides too, but we rarely hear about them because of the nostalgia associated with the material. I love steel and build with it and 95% of my personal bikes are made of the stuff, but it doesn't mean I keep my eyes closed to the usefulness of other materials.


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## shandcycles (Jan 15, 2008)

Cheap. Light. Strong. Pick any 2.


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## longcat (Apr 24, 2008)

SuspectDevice said:


> What are you going to do with the bike? There will be super huge differences between them, as they have completelely different tubesets and machine parts and intended use.


Thanks for taking time to respond.
Its for my next "only bike", I'm gonna use it as a commuter and only form of transport, probably with a rack on it, and a rigid fork. I guess the most demanding things it will see is jumping off curbs and some riding on the front wheel, but no punishement like a xc race or similar. Its a citybike.

Do you know how thick the tubes are in those 2 bikes, I guess it would be nice to have a little more robust bike that I can park/lock next to poles and stuff without worrying about dents and such. I just dont know how "durable" the lighest frame is in everyday use.



anthonyinhove said:


> The OP asked about ti as well as steel. Am I correct in thinking that ti has a different limiting factor? i.e., that as ti gets very light, it will become too flexy for XC before it will fail, so the limiting factor is flex. Whereas the limiting factor for steel is almost equal between flex and durability? And the limiting factor for aluminium is purely durability. i.e., aluminium is still stiffer than you might want, even when it has become marginal for strength - the opposite of titanium?


The biggest factor determining flex is diameter of the tubes, the thicker the less likely to flex, if you take a sheet of metal 1m long 10cm wide and 1 mm thick, you can easily find out in which direction its most flexible in, even tho its the same amount of material.

Then there is the inherent properties of the materials which plays much less difference than diameter of tubes in this case (I think), stiffness can only be applied to a construction, a part, but still different materials have different "stiffness".

I stole this from wikipedia:
http://en.wikipedia.org/wiki/Stiffness

Relationship to elasticity

In general, elastic modulus is not the same as stiffness. Elastic modulus is a property of the constituent material; stiffness is a property of a solid body. That is, the modulus is an intensive property of the material; stiffness, on the other hand, is an extensive property of the solid body dependent on the material and the shape and boundary conditions. For example, for an element in tension or compression, the axial stiffness is

k=\frac {AE} {L}

where

A is the cross-sectional area,
E is the (tensile) elastic modulus (or Young's modulus),
L is the length of the element.

For the special case of unconstrained uniaxial tension or compression, Young's modulus can be thought of as a measure of the stiffness of a material.

http://en.wikipedia.org/wiki/Young's_modulus

Material: Young's modulus (E) in GPa

Rubber (small strain) 0.01-0.1
Oak wood (along grain) 11
Magnesium metal (Mg) 45
Aluminium alloy 69
Titanium (Ti) 105-120
Carbon fiber reinforced plastic (50/50 fibre/matrix, unidirectional, along grain) 125-150
Wrought iron and steel 190-210
Tungsten carbide (WC) 450-650 
Single carbon nanotube 1,000+
Diamond (C) 1220

As you can see aluminum is only maginally better than wood, and its about the same strength too, so its a crap material, and therefor needs to be done with thick diameter tubes to combat its low "stiffness", cos if it bends its ruined.



TortugaTonta said:


> Another thing I would like to point out for those with little experience. You really can't believe the difference in "toughness" between regular 4130 and say reynolds 853 and other air hardening alloys. A crappy home depot hole saw will mitre 4130 with ease, but try one on some 853 and watch the teeth fly those tubes are amazingly tough. But also very difficult to work with when you are trying to tig a down tube onto a bottom bracket where the 853 has less than half the wall thickness of the bb shell and you vaporize the 853 long before the bb shell goes molten


I believe you think about hardness (hardness=resistance against abrasion) and strength, and strength is a direct function of hardness in these low alloyed steels (its another thing when massive amounts of carbides are involved). Toughness (impact toughness) is tested by letting a pendulum hammer drop onto the material then, you measure how many Joules it absorbed before it broke. The harder a material gets (more carbon, more alloying elements) the more brittle it is, the easiest way to make steel brittle is to add carbon, the next easiest thing is to add more than a few % of Cr (like 8-10 or so).

Neither 4130 or 4340 are real air hardening alloys, air hardening means you get full hardness (or close to it) with an air quench instead of quenching the steel in brine/water/molten salt/oil which cools more aggressively (usually air hardening steels are too high alloyed to be quenched any other way, they crack). Air hardening alloys are alloys like high speed steel, stainless hss, very high alloyed tool steel etc. To get air hardening properties (usually you want to avoid this you then have to harden it it air), you need like 5-20% Cr, a few % (like 2-4) of Mo and like 0.85%+ of C.

I bet a a good hardened and tempered piece of 4130 will be just as hard for you to saw as the 853 tubes. Normalized 4340 tubes a simply semihardened untempered tubes, which are hard but with lots off stress

I'm just guessing here but when you weld 4130 or 4340 you are actually only partially austenizing it (this is where the carbon dissolves into the steel lattice and [martensite transformation]> gets trapped there when you quickly cool it causing it to get harder since you locked carbon inside when there is no space for it) it, but instead of the aggressive water or oil it needs it gets a slow quench (and is not able to reach a full martensite transformation) therefor you lose out on the potential strength and performance.
It gets "normalized and air cooled".

all steel should be quenched and tempered otherwise you lose out imo,
this is from reynolds site

853
SEAMLESS AIR-HARDENING HEAT-TREATED STEEL
UTS: 1250-1400 MPa, density 7.78 gm/cc

sounds low compared to
http://www.matweb.com/search/DataSheet.aspx?MatGUID=b5fe87c8cdde4431b62ad990d4f2042c
http://www.matweb.com/search/DataSheet.aspx?MatGUID=cce7e56c64da4fe695b30fe3cfaed2c7
http://www.matweb.com/search/DataSheet.aspx?MatGUID=3694717896344e7caaf0fb8780da513e


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## dbohemian (Mar 25, 2007)

longcat said:


> The harder a material gets (more carbon, more alloying elements) the more brittle it is, the easiest way to make steel brittle is to add carbon


Hey, you got carbon in my iron.....No I got iron in your carbon...










so see we are not so far apart. Without carbon we can have no steel.

Dave Bohm
Bohemian Bicycles

I should advertise that I produce carbon reinforced iron-nickel-chromium-titanium alloys


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## SuspectDevice (Apr 12, 2004)

longcat said:


> Thanks for taking time to respond.
> Its for my next "only bike", I'm gonna use it as a commuter and only form of transport, probably with a rack on it, and a rigid fork. I guess the most demanding things it will see is jumping off curbs and some riding on the front wheel, but no punishement like a xc race or similar. Its a citybike.
> 
> Do you know how thick the tubes are in those 2 bikes, I guess it would be nice to have a little more robust bike that I can park/lock next to poles and stuff without worrying about dents and such. I just dont know how "durable" the lighest frame is in everyday use.


I would guess Ian uses the hoxplat07 TT. that's a 7/4/7 with a pretty long reduced section. You aren't going to dent it leaning it anywhere though. If you decide to start throwing your bike against poles, or using it as a mallet for polo....


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## Rody (Sep 10, 2005)

longcat said:


> Thanks for taking time to respond.
> Its for my next "only bike", I'm gonna use it as a commuter and only form of transport, probably with a rack on it, and a rigid fork. I guess the most demanding things it will see is jumping off curbs and some riding on the front wheel, but no punishement like a xc race or similar. Its a citybike.
> 
> Do you know how thick the tubes are in those 2 bikes, I guess it would be nice to have a little more robust bike that I can park/lock next to poles and stuff without worrying about dents and such. I just dont know how "durable" the lighest frame is in everyday use.


Seriously...this whole discourse that has played out over the last week has been to aid in the decision of whether or not a pound in frame weight is going to make a difference to the OP in his "City Bike" that he plans on using with a rack?

Dude, get the heavier frame and ride it knowing that it will last a lifetime under your use and smile when you think of how much more fit you will be for pedaling the extra pound of non-rotating center mass.

seriously? you betcha! :thumbsup:

rody


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## Walt (Jan 23, 2004)

*Agreed*

For a city bike? Seriously?

Best troll ever, I think! If this whole thread was really about what frame to use for a townie, then I have to say, gentlemen - we've been had!

-Walt



Rody said:


> Seriously...this whole discourse that has played out over the last week has been to aid in the decision of whether or not a pound in frame weight is going to make a difference to the OP in his "City Bike" that he plans on using with a rack?
> 
> Dude, get the heavier frame and ride it knowing that it will last a lifetime under your use and smile when you think of how much more fit you will be for pedaling the extra pound of non-rotating center mass.
> 
> ...


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## perttime (Aug 26, 2005)

Walt said:


> If this whole thread was really about what frame to use for a townie, then I have to say, gentlemen - we've been had!


Oh, I think some of us may have learned something about frames in the process, whatever the OP.


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## anthonyinhove (Nov 3, 2007)

Rody said:


> Seriously...this whole discourse that has played out over the last week has been to aid in the decision of whether or not a pound in frame weight is going to make a difference to the OP in his "City Bike" that he plans on using with a rack?
> Dude, get the heavier frame and ride it knowing that it will last a lifetime under your use and smile when you think of how much more fit you will be for pedaling the extra pound of non-rotating center mass.
> seriously? you betcha! :thumbsup:
> rody


I strongly disagree. He who pays the piper calls the tune, Mr Groovy, and whatever the purpose a prospective buyer might have, there is surely a sensible discussion to be had with him as to what is the 'right' weight strategy to employ in choosing a tube spec. You of all people are renowned for the rewarding nature of those discussions, so I can't really believe that you truly meant that.

If durability were the only criterion, what you say here might be correct, but it is not. Enjoyment is another criterion, and heaping excess weight into a frame just for the sake of durability and making him a dead-feeling frame rather than a springy-feeling frame, will surely reduce the guy's enjoyment of the cycling experience, even if it is mainly around town. And who knows, if he *really* enjoyed cycling around town on his optimal-lightweight mtb, might he not be tempted out into the great wide yonder someday?


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## DWF (Jan 12, 2004)

anthonyinhove said:


> I strongly disagree. He who pays the piper calls the tune, Mr Groovy, and whatever the purpose a prospective buyer might have, there is surely a sensible discussion to be had with him as to what is the 'right' weight strategy to employ in choosing a tube spec. You of all people are renowned for the rewarding nature of those discussions, so I can't really believe that you truly meant that.
> 
> If durability were the only criterion, what you say here might be correct, but it is not. Enjoyment is another criterion, and heaping excess weight into a frame just for the sake of durability and making him a dead-feeling frame rather than a springy-feeling frame, will surely reduce the guy's enjoyment of the cycling experience, even if it is mainly around town. And who knows, if he *really* enjoyed cycling around town on his optimal-lightweight mtb, might he not be tempted out into the great wide yonder someday?


There are two parties in every transaction. If a builder doesn't agree with what the "customer" want, he just tells him no, shop elsewhere. The customer is not always right.


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## dbohemian (Mar 25, 2007)

I agree with DWF. 

I will say though that at least with the customers I have had, not one time can I think of that any one of them seemed concerned with weight or tube choice but instead just deferred to me to make the right decision for them.

Isn't that why they are purchasing from a professional? 

Dave Bohm
Bohemian Bicycles


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## themanmonkey (Nov 1, 2005)

anthonyinhove said:


> heaping excess weight into a frame just for the sake of durability and making him a dead-feeling frame rather than a springy-feeling frame, will surely reduce the guy's enjoyment of the cycling experience,


Looking at your previous posts I can't figure out if you're trolling or just have bought the whole weight thing hook-line-and-sinker. Weight and material has little to nothing do do with "dead-feeling" or "springy-feeling." Where are you getting this stuff?


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## Walt (Jan 23, 2004)

*Good point.*

Yes, that's certainly true. It was a productive discussion, regardless of the original intent of the OP.

You have to admit that it's funny, though.

-Walt



perttime said:


> Oh, I think some of us may have learned something about frames in the process, whatever the OP.


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## anthonyinhove (Nov 3, 2007)

themanmonkey said:


> Looking at your previous posts I can't figure out if you're trolling or just have bought the whole weight thing hook-line-and-sinker. Weight and material has little to nothing do do with "dead-feeling" or "springy-feeling." Where are you getting this stuff?


You do yourself no credit by being offensive. You should have respect for others, and assume that if they take the trouble to say something it is on the basis of personal experience and knowledge, even if that differs from yours.

I am quite light and my personal experience is that I have yet to find an mtb frame that felt too light for me, either in terms of excessive flex or concerns about its strength. When I have ridden bikes that were heavier - of thicker-gauge tubing, even plain gauge, these often had a dead feeling, compared to the springyness of a frame with thinner-gauge tubing. I personally don't care what a frame weighs per se, but I have found weight to be a reasonably good proxy for springy and I have found that frames with more compliance are faster (for me) in give-and-take cross country riding. A stiffer frame gives better power transfer, but for me can feel less stable the rougher the terrain gets, which makes it slower over a distance.

I know plenty of people who have broadly the same experience and tastes as this. If you feel on the basis of your own experience that a heavy plain-gauge frame is just as springy and lively as a light double-butted one, I should find that very interesting news.

Personally I felt the OP's question was worthwhile, although it seems a little abstract until you define the circumstances. Once you know what kind of rider somebody is and what kind of stuff he/she wants to do, you then have a range of choices between tubes of different characteristics (inter alia weight), which give them a variety of different end products. On one extreme of that range may be the answer to the OP's question for that particular rider.


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## Rody (Sep 10, 2005)

anthonyinhove said:


> Once you know what kind of rider somebody is and what kind of stuff he/she wants to do, you then have a range of choices between tubes of different characteristics (inter alia weight), which give them a variety of different end products. On one extreme of that range may be the answer to the OP's question for that particular rider.


Anthony, I totally agree, and as such, that's what I posted in the OP's first response.

I guess I was taken aback. Here is a thread that has generated much response, both positive and negative, as many have debated the design, construction, and physical characteristics/limitations of the custom bicycle frame.

The irony is that the piece of the puzzle that has been missing all along is that the OP is trying to decide if a 1 pound differential will make that much difference for his city bike with a rack that is being purchased off the rack from a manufacturer.

Makes me shake my head and laugh because so many have invested much time in this dialog when more complete communication from the start would have answered his query in a hour rather than a week.


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## themanmonkey (Nov 1, 2005)

anthonyinhove said:


> You do yourself no credit by being offensive. You should have respect for others, and assume that if they take the trouble to say something it is on the basis of personal experience and knowledge, even if that differs from yours.


I'm not being any more insulting than you folks that aren't actually reading and digesting what we're saying. We are professionals in this field, this is what we do, period. I've owned around 100 different bikes in the last 30 years and ridden thousands more. These aren't some personal opinion of some random rider guy, this is an educated professional opinion. Do you have a profession? What do you think when non-professionals start talking about how they know as much as you do?

If you want specific information about a bike for YOU IN SPECIFIC ask that question don't hide it in general myth and hype. Until we know what your riding style, weight, age, etc is we can't talk beyond the general. Sure I could build you a sub 3 lb steel frame, but there have to be a few caveats. 1. You weigh under 150 lbs. 2. For cross-country use only. 3. $2200 ($1000 non-refundable up front). 4. NO WARRANTY or refunds. 5. Sign a legal waiver that I am in no way liable if you hurt yourself.


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## longcat (Apr 24, 2008)

I'm sorry for wasting all your precious time with my unserious questions and "unseriuos" not worthy for this forum intent for this frame, I'm better off with a walmart bike right, and that would save me some cash. :thumbsup: 

So what if I'm only using it around town, does it matter? I still want a good frame, and now I know what too look for, I'm very happy everybody took their time to contribute since I learned a lot, your time was not wasted.

I dont know why I should limit myself to lower standards than people riding their bikes in the woods, why would I want any lesser frame? I'm using my bike every day, I depend on it, its important too me that I choose the right frame since I will use it every day.

I dont know about you guys but I feel its more important to get a good frame for every day use than good frame I will use racing what once a month or once a week. Maybe my priorities are off I dont know.


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## longcat (Apr 24, 2008)

Rody said:


> the OP is trying to decide if a 1 pound differential will make that much difference for his city bike with a rack that is being purchased off the rack from a manufacturer.
> 
> Makes me shake my head and laugh because so many have invested much time in this dialog when more complete communication from the start would have answered his query in a hour rather than a week.


I actually had decieded on a custom since I couldnt find any frame that had what I wanted,
slack head tube for a short/eventually rigid fork, steel, not DJ-heavy or DJ-size. It just turned out I could get all that right off the shelf. Sure this will cost me custom money (if not more) , but there is an importer here so I can get it right away. Yeah and btw to me a pound or 2 matters since I have to carry it.


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## Walt (Jan 23, 2004)

*Yes.*

I have ridden virtually identical (ie, same general geometry and same tube diameters) straightgauge and butted tubing frames head to head. They do ride the same, at least as far as I can tell. And I've ridden an awful lot of bikes.

If you do some research you'll find that the tube wall thickness (at least in the range we're talking about) has very little effect on how much a tube will deflect under load. Diameter is everything.

I'm guessing that the beefier frames you've ridden have had bigger diameter tubes, as well as being heavier (and they might very well have had beefier stem/bar/post/wheels which will make a huge difference as well), and that's probably where you're feeling a difference.

To each their own, though - you want what you want, and the OP is right to say that there's nothing wrong with wanting a good city bike that will work exactly right for what they want to do. I apologize for being snide earlier - I'm the type who generally uses dumpster bikes as townies, just because there's a decent amount of theft around here. That doesn't mean my idea of a good townie is the only way to go, though.

-Walt



anthonyinhove said:


> I know plenty of people who have broadly the same experience and tastes as this. If you feel on the basis of your own experience that a heavy plain-gauge frame is just as springy and lively as a light double-butted one, I should find that very interesting news.


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## themanmonkey (Nov 1, 2005)

longcat said:


> I dont know about you guys but I feel its more important to get a good frame for every day use than good frame I will use racing what once a month or once a week. Maybe my priorities are off I dont know.


*longcat* go back and read all the posts again. No one is saying you shouldn't get what you want and that a bike can't be light. We're saying light doesn't matter as much as folks have it worked into their heads. This is particularly true with a bike you're going to bang around town on. Lets break it down to simple terms of a 3.5 lb frame vs. 2.5 lb frame, lets go one step further and say that the custom fork will be 2 lbs vs 2.5 lbs. So total frameset weight is 4.5 lbs and 6 lbs. Now add 25 lbs of parts, fenders, rack, etc which would be a middle of the rad weight estimate.

Now we're at 29.5 and 31 lbs respectively for the bikes. the 1.5 lb weight difference doesn't seem that different now does it? You'd be lucky to tell them apart if you lifted them up. Add yourself and some cargo and the 1.5 lb difference has virtually disappeared. You and *anthonyinhove* have this less weight = automatically better ride in your minds when it's not the truth. A builder can build you a 2.5 lb frame that rides like crap and a 5 lb frame that rides like a dream the weight is not a matter.

Personally I'm a total weight dork, but I know it's all in my head. I was around building up sub-20 lb. MTBs with sus forks 15 years ago and I see how few of them are around these days. Most of us on this list have been down this road before in the past and saw where it lead. I'm all for people making their own mistakes, but just don't ask for advice and then ignore it like it wasn't given.


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## longcat (Apr 24, 2008)

Just one last question: will the samurai and sakura feel pretty much the same regarding plushness/springyness you guys think? they look pretty similar in diameter of tubes etc judging by the pics. Thanks. Take care and merry xmas


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## pvd (Jan 4, 2006)

The way I ride, a bike will weigh 26-27 lbs (hardtail) and 30 lbs (FS). Any lighter and the bike either sucks to ride or is constantly breaking. Ride quality is so important and so many people focus on weight so much more.

When I see people (normal size) on sub 27 lb FS bikes, I always wonder, "How slow do you have to ride to keep that thing together?"


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## SuspectDevice (Apr 12, 2004)

longcat said:


> Just one last question: will the samurai and sakura feel pretty much the same regarding plushness/springyness you guys think? they look pretty similar in diameter of tubes etc judging by the pics. Thanks. Take care and merry xmas


The yokes and big ole rectangular chainstays on the Samurai are going to make it a whole lot stiffer in the rear. Tons and tons and tons. It is certainly massive overkill for what you want.


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## jmoote (Aug 31, 2007)

pvd said:


> The way I ride, a bike will weigh 26-27 lbs (hardtail) and 30 lbs (FS). Any lighter and the bike either sucks to ride or is constantly breaking. Ride quality is so important and so many people focus on weight so much more.
> 
> When I see people (normal size) on sub 27 lb FS bikes, I always wonder, "How slow do you have to ride to keep that thing together?"


This really is a function of how and where you ride though. I don't ride with suspension, but would say that I ride fast for my terrain and the bike I'm on. If I put the parts from my rigid 29er on a 4lb hardtail frame with a Fox F29, it would be a 25 lb bike. Project that to a 6.5 lb full suspension frame and that's 26.5 lbs. With 26" wheels it would easily be 2 lbs less, so for me/my area, a 30 lb full suspension is too much bike by about 4-5 lbs. I didn't build my bike around weight, but with smart choices for its intended use, a 23.5 lb bike was the result. For people with real mountains, real rock gardens, etc I can totally see the proper bike being that much heavier. It comes down to what you want the bike for.


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## anthonyinhove (Nov 3, 2007)

pvd said:


> The way I ride, a bike will weigh 26-27 lbs (hardtail) and 30 lbs (FS). Any lighter and the bike either sucks to ride or is constantly breaking. Ride quality is so important and so many people focus on weight so much more. When I see people (normal size) on sub 27 lb FS bikes, I always wonder, "How slow do you have to ride to keep that thing together?"


I appreciate that I should feel ashamed of myself because I'm not even a good enough rider to break my 23lb hardtail, but may I ask what would it be that would be 'constantly breaking' if you rode it? Say my Columbus Cyber frame (28.6 x 7-4-7 top tube, 31.8 x 8-5-8 down tube etc, no fancy tube shaping, no gussets, weighs 4.2lbs painted). To be specific, is your experience that it would be the tubes that you would break or the welds?


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