# short vs. long chainstay climbing traction



## adinpapa (Dec 4, 2007)

I'm beginning the custom frame design process and need some input strictly through a singlespeed perspective. 

I have always assumed short CS mean more traction (weight over wheel). Yet on a painful long techi climb yesterday, I had this desire for my Pivot LESS to have a longer rear end for traction. (Medium LES is 434mm CS) . 
I desired less rearward movement of hips to maintain traction... 

I understand the benefits of short CSs for cornering and 'flickability', yet with the longer reach, slacker, and dropper post all contributing to improved descending, shouldn't the rear be a bit longer to balance the front? Is there a sweet spot here, or will shorter always result in greater traction? 

Some starting geo numbers I'm mulling over with a 120mm fork : (feedback welcomed!) 
68 HTA , 455mm Reach, 30.8 BB ,


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## mack_turtle (Jan 6, 2009)

I am starting to think that CS length and BB drop need to be considered in relation to one another, as well as reach. actually, the whole geometry needs to be taken into account. if the reach is too long, it will be hard to get weight over the rear axle no matter how short the chainstays are.

are you shooting for a 31mm BB drop? that's a HIGH bottom bracket!

455mm is extremely long in reach for a medium. I think the medium Honzo is not even that long. how tall are you and what size stem would you plan to run with something that long? that might make you feel very stable and "in" the bike but I can't see that being very nimble, especially at low speeds over chunk.

do you have some experience with a few past frames for reference?


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## adinpapa (Dec 4, 2007)

Thanks for the thoughts _turtle . 

Indeed everything is connected in the geo. I'm trying to get a sense of what can be changed independently, and what impacts it will. Such as extending CStays while keeping reach and BB height 

No I have not been on many similar bikes - and no hardtails. I would like to get on a Spot SS or Honzo to compare to my LES. 

Only a brief ride on a RM Element , around 450reach. 
and a very short spin on the Intense Sniper, large. 468mm reach.
The Sniper felt really good.. like ride it-like-a-singlespeed-put-the–power-down type of good.

Correct, the medium Honzo is 450mm 

The Pivot LES BB Height is listed only at 30.7 mm (with 100mm fork)


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## mack_turtle (Jan 6, 2009)

don't take this the wrong way, but be sure you know what those numbers mean before you order a custom frame.

the 30.8 BB you listed is the _BB height, in centimeters, from the ground_. that's a reasonable BB height. so that's a 308mm high BB. the higher the BB, the fewer pedal strikes you will get. depending on the wheel/tire size, a higher BB will also require less _drop_, which means a compromise in handling.

BB drop is usually listed in millimeters and measures how low the BB is from the axles. that number ranges 50-70mm and affects how the bike handles- higher being more "nimble" and lower being more "stable." that's all subjective though. also be sure to know if that BB height/drop takes suspension into account, assuming you're going to use a suspension fork.

as for reach, that's also personal preference and your body dimensions. I am of the opinion that long frame reach has gotten absolutely out of hand. at 5'9", my frame reach is about 440mm with a 70 HTA and I have to use a 50mm stem and a handlebar with a lot of sweep/backward offset to make it tolerable. it worked out for me in the end, but I could use a not-so-long stem and a more conventional handlebar if the reach was not so incredibly long. different bikes made for different kinds of terrain might work better.

I suggest you work closely with your bike fitter and consider the geometry of what others riders near you like to figure it out.


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## *OneSpeed* (Oct 18, 2013)

It's a complicated and involved conversation. What do you want out of the custom frame that the Les doesn't give you? If you could change your current bike what would you change and why?

Some people liked old school XC geo, it worked well for what it was. Others prefer modern geo, for good reason IMO.

The Kona Raijin is still my benchmark for what I consider modern XC geo. KONA BIKES | MTB | MTB HARDTAIL | Raijin I would want a considerably longer reach for my personal frame size (XL), but otherwise this is pretty close to the custom frame I had made last year.

As for CS length, I'm definitely in favor of shorter chainstays. 415-435 depending on what your after. When you stand to climb SS, your weight is shifted forward. If you put the rear wheel too far back there will be less weight on it and you'll lose traction easier.

(side question: where you sitting or standing on the long tech climb you described?)


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## adinpapa (Dec 4, 2007)

mack_turtle said:


> as for reach, that's also personal I suggest you work closely with your bike fitter and consider the geometry of what others riders near you like to figure it out.


Thanks for the explanations . I get the difference between bb height and drop. I'm of the mindset that bb should be as low as it can be , for the type of riding I do. The LES is pretty dialed in that way- few strikes and great for dropping weight into corners.

Sounds like I need to slow this process down and read more.

Sent from my iPhone using Tapatalk


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## adinpapa (Dec 4, 2007)

*OneSpeed* said:


> (side question: where you sitting or standing on the long tech climb you described?)


Standing , weight back front end light and avoiding chunk . I was under knobbed out back (Mezcal) and 2 hrs into a hard ride , but still... 
Sitting climbing is usually fine - I can get cadence up and maintain traction and control

Sent from my iPhone using Tapatalk


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## *OneSpeed* (Oct 18, 2013)

adinpapa said:


> Standing , weight back front end light and avoiding chunk . I was under knobbed out back (Mezcal) and 2 hrs into a hard ride , but still...
> Sitting climbing is usually fine - I can get cadence up and maintain traction and control


So you were forced to keep your weight back over the rear wheel to keep traction, which sucks while standing on a SS, and it caused the front end to get light? Also the Les has a really short reach which will cause the front end to come off the ground more easily.

A longer front end and shorter chainstays shift weight forward. The Les also has a slack STA (not as important on a SS where your standing a lot of the time) but I'd still want the STA in the 74-75 degree range.


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## mikesee (Aug 25, 2003)

adinpapa said:


> I desired less rearward movement of hips to maintain traction...


This points to needing (or at least wanting) to _shorten_ the chainstays, which would bring the wheel up under your CoG more, which would give you better traction.


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## coleam (Aug 8, 2009)

adinpapa said:


> Sounds like I need to slow this process down and read more.


Probably a good idea. If you're on a medium LES (short reach for a medium) and a large Sniper (pretty long reach for a large) felt right, then you may want to put a lot of thought into the reach you want - more so than the chainstays (the LES and Sniper aren't so different in that respect - the Sniper's chainstays are ~4mm longer). To put things in perspective, the large Sniper is a full 55mm longer in the reach department compared to the medium LES. That's a massive difference. You're probably running a longer stem on the LES, which would compensate for it a bit, but that gives a totally different feeling to the steering. Maybe look into getting a professional fit done to get a ballpark of the numbers you should be looking for in terms of stack/reach/seat tube angle, then test some bikes with similar measurements to see how they feel on the trail.


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## adinpapa (Dec 4, 2007)

Thank you all for your thoughts.

I do see a bit of a contradiction in these statements above, that relate to my original inquiry - short vs. long CS:

OneSpeed (post #8): A longer front end and shorter chainstays shift weight forward.

mikeSee (#9): This points to needing (or at least wanting) to shorten the chainstays, which would bring the wheel up under your CoG more, which would give you better traction.

It sounds like long front and short rear brings weight forward (reducing traction assumedly) yet short CS wheel under improves traction... So the long front brings weight forward yet without reduction in traction if CS are short so wheel is tucked?

I stayed up too late digging into Peter Verdone's writings. 
I know he's a staple around here. As a noob to geometry philosophies, I really enjoyed his blog. I'll leave this here, in case any other's aren't privy to his Forward Geometry approach Forward Geometry | Peter Verdone Designs
and a more recent project: 'Blackbird' SR-71 Blackbird | Peter Verdone Designs

It's fantastic reading his iterations on different bikes and the detail how handling is impacted.

My tight New England trails and marathon race ambitions, have me looking for a singlespeed focused bike with a 'Forward' approach a bit less extreme than PV's, but I'm starting to get how it fits together and the benefits of 'long , short, low' . I get lost with the Front Center references...

Is the 'Front Center' value something to design to ? Or is it a by-product of a the other key numbers (reach, STA, CS, drop) ?


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## *OneSpeed* (Oct 18, 2013)

adinpapa said:


> I do see a bit of a contradiction in these statements above, that relate to my original inquiry - short vs. long CS:
> 
> OneSpeed (post #8): A longer front end and shorter chainstays shift weight forward.
> 
> ...


Mike and I were saying the same thing. Based on your description you want/would benefit from shorter chainstays, not longer. If you only shorten the chainstays on your current bike the front end would come off the ground even more than it currently does. In order to counteract that when you shorten the rear end you need to lengthen the front to balance it back out. (as someone else pointed out the Les has a very short reach).



> I stayed up too late digging into Peter Verdone's writings...
> 
> It's fantastic reading his iterations on different bikes and the detail how handling is impacted.


Agreed, it's entertaining to read, but don't design your bike around an extreme example of what one guy thinks is great, especially if you can't experience it yourself before you commit.



> My tight New England trails and marathon race ambitions, have me looking for a singlespeed focused bike with a 'Forward' approach a bit less extreme than PV's, but I'm starting to get how it fits together and the benefits of 'long , short, low' .


Think "modern" not necessarily "forward". Keep reading about recent/current hardtails and SS frames. Take notes and compare to your current bike, and/or what you think you want out of the custom frame.



> Is the 'Front Center' value something to design to ? Or is it a by-product of a the other key numbers (reach, STA, CS, drop) ?


Depends who you ask.


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## mack_turtle (Jan 6, 2009)

https://singletrackworld.com/forum/topic/chainstay-length-vs-bb-drop/

Relevant

also go read the Frame Building forum. Walt has some good insight on the topic of BB drop and CS length.

I would design the bike around building it so the grips and the BB are in the right place relative to one another to maximize your range of motion. I subscribe to Lee MacCormack's theory, which favors a pretty short reach + short stem. then figure out what balance of flickability and stability you need with the back end.


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## alexbn921 (Mar 31, 2009)

Chain stays are some what limited by the size of wheel/tire you are using. Most manufactures design frames around a medium sized rider and basically use the shortest CSL they can design around the rear wheel.

One thing to note. Long front center and short rear = More weight on the back wheel. When you shift the BB backwards with a shorter rear or a longer front, you increase the weight on the rear axle. This is a ratio and needs to be monitored when changing frame size.

I'll give my perspective as a very tall rider. Short chainstays suck! Having a 505 reach with a 50/60 stem shifts the majority of my weight to the rear axle. Getting that weight back on the front requires a low handle bar height or some weird body positions.

The bike is a system and must be considered as a whole unit. Your size will have a dramatic effect on how the bike needs setup. The relationship of the front to rear lengths, seat tube angle, preferred handlebar height..... All have an effect.

New bikes with short stems = same rider position as old bikes with long stems. CG is the same but the front center is longer
Longer front center = more weight on rear axle.
Shorter stays = more weight on rear axle.
Slacker seat tube = more weight on rear axle and moves your CG back while seated.
Larger BB drop makes bikes more stable.
Short stems speed up steering
Long bars slow down steering
Slack HTA slow down steering.
Less fork offset adds trail (centering effect) and reduces front center.
Higher handlebars = more weight on the rear axle.
Even things like tire/rim weight change how nibble a bike feels.

If you can climb steep hills to the limit of traction without flipping over backwards and you like the stability of your bike then your CSL is fine.


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## ninjichor (Jul 12, 2018)

You want a longer front center, to combine with short CS.

[HR][/HR]
A longer front center has the effect of making your position, to get balanced weight distro between the wheels, more forward than usual. This has a side benefit of making the front pitch up less over bumps, making them feel smaller.

Rear center (RC, aka "horizontal chainstay length") being lengthened would encourage you to be more rearward for proper weight distro. A shorter CS has the downsides of limiting clearance for the tire, chainring, and making bumps feel bigger. Bumps feeling bigger in the rear is sometimes seen as added challenge though, encouraging the rider to be more active/engaged, and such challenge+engagement is considered to be more fun. If you get lazy, your rear will take a pounding though. If you're more of a cruising/lazy rider, you'll be better off with longer CS. Lazy riders, who prioritize comfort above all else, benefit from long CS as it offers good control and safety with the rider hanging behind their saddle on descents. It also allows them to run extremely low gearing, without the torque causing their front tire to lift, which forces other riders with short CS to move to the tip of the saddle. Low gearing isn't ideal for tech though...

[HR][/HR]
Good cornering comes from good traction, plain and simple. Having a good weight balance and low CoG, helps to keep the bike from feeling unsettled and inconsistent.

Flickability comes from lightness foremost, especially at the extreme ends, as you're fundamentally working against a "moment of inertia" measured from where you're touching the bike, to the far end of the wheel you're trying to flick.

Improved descending comes from improved stability and control, and reduced feedback. Suspension, longer wheelbase, tires that don't bounce...

Regarding "greater" traction... what you want is to not increase your max traction, but to increase your minimum traction, so the variance between minimum and max traction is not so extreme. You wouldn't be able to take advantage of having velcro-like traction on granite if you're trying to be careful, watching out for those super traction moments, like that one slimy moss covered bit of rock in the shade, keeping things in check in case you run into it.

[HR][/HR]
Getting geo right is a juggling act, as it determines weight distro, which is all important. How something carries its weight is something that cannot be understated.

I advise you to get the lowest BB you can get away with. Don't be afraid to go extreme with lengthening the front and steepening the STA, to get your position where you like it. Show the builder a photo of your natural standing position, and simply suggest that you want the front lengthened enough to have the seat moved under you, so the standing and seated position kind of match, both offering sweet spot weight distro.

Personally, I'm not picky enough to get another bike just so I am more comfortable holding a position that grants better traction. If I must push my hips back when out-of-the-saddle, to an area above where my saddle would be, to get traction, I'll do it and practice/work on generating power more efficiently from that position.


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## *OneSpeed* (Oct 18, 2013)

^ that was a lot of mostly useless words with a few bits of accurate info. Making suggestions based on a seated climbing position and a low climbing gear? Doesn't happen much on a SS. Hence the SS specific question.


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## mack_turtle (Jan 6, 2009)

Generally speaking, I am always weary of advices about SS bikes from the perspective of gearies. You don't ride SS the same way you ride a geared bike. Rigid and hardtail riding also changes the technique required to wrangle the bike such that you need to tweak your approach to riding and bike setup.

Bottom line is that you need to get what works for you the way you ride your trails. I am still weary of these super-long bikes with the BB practically dragging on the ground as those are features I don't want on a singlespeed bike on my local terrain. I am sure that kind of thing is great for shuttle runs on actual mountains though.

I agree with something that someone said above- chainstay length and rider height do have some correlation. I met a guy who was riding a Unit the other day and we got talking about bikes. I told him I never had interest in the Unit because of the long chainstay. He said that, being nearly six and a half feet tall, he wishes the CS was longer so he could keep the front wheel down. That makes sense to me.

Pete Verdone Blackbird is probably a great bike- for him, on his local terrain, for his riding style.


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## *OneSpeed* (Oct 18, 2013)

^ I won't argue because bike setup, terrain, and personal preference make a big difference in one persons description of a bike (or geometry, or component) will vary greatly from someone else's, as we know. 

Being 6'3" and riding the Honzo in a couple different configurations with 415mm chainstays I never once though anything other than "this is awesome and much more balanced than I expected". Actually the BB was a bit low, but the other seemingly "extreme" (compared to my old XC Kona Unit) geometry numbers don't translate to how the bike handles. When you add it all up and actually ride it, it really works well together. 

Having also owned a Unit with 440 ish (I forget) with old school XC geo, I never felt that bike was unbalanced either. It was seriously different but worked as it was designed to, but I honestly never felt that the geometry was flawed in any way. If another frame became available at a reasonable price in XL (I still look almost weekly) I'd buy it in a heartbeat. I still have all my old parts. 

As others have stated, it's really about the whole package. You shouldn't single out any one dimension of a frame and expect to know how it will handle or fit. You have to consider the big picture, and that's where I think picking the right frame builder and good communication is the most important part of the process.


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## mack_turtle (Jan 6, 2009)

With all that has been said, does OP not trust his frame builder to do it right without a ton of specifics? A good frame builder should be able to take your measurements, and make a frame that fits and handles well for your riding style.


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## adinpapa (Dec 4, 2007)

This has all been really helpful. I'm currently compiling a Google Sheet of many modern bikes to compare geo numbers. I'll post it here if others are interested to see or add to. 

For tomorrow's ride, I'm going to adjust my LES with a longer stem to play with reach a bit (knowing handling will be different than a bike designed with longer reach/shorter stem)

In terms of frame builder relationship.... I'm still considering custom steel or ti and getting reality checked around budget etc. Building a race whip with proper trail properties in a <4lb frame, may be asking too much.

Before engaging builders, I'm doing my research first. As a consultant in the home energy efficiency field, I always appreciate a well informed client that I can get deep with real fast because they understand core concepts.


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## ninjichor (Jul 12, 2018)

*OneSpeed* said:


> ^ that was a lot of mostly useless words with a few bits of accurate info. Making suggestions based on a seated climbing position and a low climbing gear? Doesn't happen much on a SS. Hence the SS specific question.


What's not accurate? It's generalized based on the info they gave. If they want more precise advice, they need to supply more info.

How's it useless? I'm sensing some logical fallacy coming from your end. What gives you the jurisdiction to judge the usefulness of my advice, which I gave to @adinpapa? You got some special SS armband? Stasi? Is speaking of low gearing and seated positions immediate disqualification? Consider the context, I said low gearing when referring to lazy/cruising types of riders (heavyweight riders esp), leading to a front tire lifting (a sign of weight being too rearward). I mentioned seated position in relation to standing, to give the idea that shrinking the difference between the two would be a step in the right direction, which assumes that the bike designer makes the weight balance sweet spot very close to the seated position (generally a little forward of it). I gave an example, saying that I have my hips pushed back, above where my saddle would've been, to hit the weight distro sweet spot (e.g. for traction to climb up loose gravel).

I told @adinpapa, with confidence, what they need to know. It's a straight-forward solution to their problem: they're losing traction on climbs, and feel a need to push their hips back to improve traction. They were looking for geo advice to go custom. They had concerns with cornering and flickability, and seemed confused about longer reach, slacker HTA, and droppers needing to be balanced somehow. Based on the starting numbers they gave, I simply put that they need to go longer up front, in combination with a short rear. I gave reasons why, and suggested the numbers that would suit them would be much beyond their starting ones, to a range that may be scary/unknown. I suggested what kind of rider would want long chainstays.

More info, like videos from many angles in which this problem can be witnessed, and words describing how they feel in those scenarios, and how they want to feel, would enable more useful advice. I'm working on open possibilities, not trying narrow my perspective based on limited statistics and assumptions. @adinpapa didn't divulge any personal info really, such as gender, let alone if they were a SS jock. If there's any clarification needed with what I posted, ask more specifically. If there's an error, correct it. Casual judgement is worthless.

P.S. I'll admit that I forgot to type in "low", when speaking of minimizing the difference between max traction and "super *low* traction moments". Hopefully that didn't confuse anyone too much.


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## geraldooka (Jul 3, 2012)

I’ll keep out of every geo suggestion but one B.B. height (drop) primarily because this one has a hard target for everyone. It may be low for some and higher for others but there is always a limit or range one is willing to live with. So consider that figure carefully as there are limited options to change it in the future. Think about your preferred crank arm length, tire sag, fork sag, terrain etc. 

Everything else won’t make for an unrideable bike, you may not like it but altering head angle with an angle set is easy, moving your saddle to alter seat angle is easy and if you get sliders you could even adjust your chain stay by up to 15 or so mm...


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## ninjichor (Jul 12, 2018)

Shortening your crank allows for lower BB. There's all sorts of fear and bias surrounding that, like less torque output, but it's overdramatized. Less torque from the crank is similar to getting less torque from your gear ratio. Losing 5mm of crank length is equivalent to gaining 1 tooth on your chainring. There's a surprising amount of research done on the topic, and I'm convinced that there's plenty of room to go shorter, getting overall gains (I'd dare to go 155mm).

I suggest reading up on Walt's experiments on the BB height and crank length (and chainstay length) topic here: http://forums.mtbr.com/26-27-5-29-plus-bikes/paradigm-drift-omg-i-built-myself-bike-1078271.html


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## geraldooka (Jul 3, 2012)

ninjichor said:


> Shortening your crank allows for lower BB. There's all sorts of fear and bias surrounding that, like less torque output, but it's overdramatized. Less torque from the crank is similar to getting less torque from your gear ratio. Losing 5mm of crank length is equivalent to gaining 1 tooth on your chainring. There's a surprising amount of research done on the topic, and I'm convinced that there's plenty of room to go shorter, getting overall gains (I'd dare to go 155mm).
> 
> I suggest reading up on Walt's experiments on the BB height and crank length (and chainstay length) topic here: http://forums.mtbr.com/26-27-5-29-plus-bikes/paradigm-drift-omg-i-built-myself-bike-1078271.html


I'm not sure if that's in reply to me or not. If so I didn't suggest it wasn't possible to shorten your crank just that it is more difficult as an option to fix a too low B.B. there are very few cranks on the market shorter than 170 especially if you are looking for lightweight and performance oriented. I have the White Brothers MR30 which are excellent, still the shortest is 165 and SRAM have a 165 but it's really a 170 with an offset pedal hole. There's Canfield but they weigh a ton. That's really about it.

I'll leave the power torque debates to others as I give zero F's to that.


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## adinpapa (Dec 4, 2007)

@ninjochor, thanks for your contributions- helpful. I've read Walt's crank stories. I"d be willing to try a 170 , but I just invested in an eeWing 175mm (after breaking 2x Nexts SL, one that put me out of a race battling for first ,five hours in) ... I'll be sticking with 175 , hopefully for a very long time.
It will be interesting if shorter cranks catch on. Personally, I think my Pivot LES (M) has an ideal BB height for me and will likely be going with that... it drives the corners with very occasionally pedal strikes.


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## mack_turtle (Jan 6, 2009)

ninjichor said:


> Shortening your crank allows for lower BB.


shorter cranks might mean fewer pedal strikes. that is not the only reason why some prefer a higher BB. some riders prefer the handling characteristics of a higher BB and where that puts the CoG. think of the extremes of BB drop (regardless of how they effect height): a trials bike with the BB above the axles, and a touring bike with the BB far below the axles. higher CoG makes the bike easy to toss around while jumping, while the latter's low BB makes it stable while riding long distances on roads while loaded down with camping gear. a typical mtb ought to be somewhere in the middle.

for where and how I ride, I sometimes would like my bike to be easier to pop the front end up while I wrangle a rigid bike over rock gardens. you can do this by shortening the reach (not preferable), shortening the CS (harsh and hard to do after a certain point), or raising the BB a bit. the question is: can you overcome the difficulty of handling a low-BB bike by shortening the chainstays, or should you keep the BB high and let the CS be long. that's why there are several bikes on the market for different riders with different styles.

some people just ride and don't care. ignorance is bliss, but as someone pointed out to me the other day, awareness is euphoria.


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## geraldooka (Jul 3, 2012)

mack_turtle said:


> shorter cranks might mean fewer pedal strikes. that is not the only reason why some prefer a higher BB.i


True. Something I read recently that I had not considered is the concept that a higher B.B. may actually ride smoother given that you are closer to the axle path as the wheel rolls over obstacles... That sounds interesting.

The Radavist recently review a Kingdom hardtail which has a very high by modern standards 30mm drop and thought it ripped...


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## ninjichor (Jul 12, 2018)

I find that 5" trail bikes with a 1150mm wheelbase seem to work well with a 420mm CS. It gives me a nice balanced feel when out of the saddle, where I can just carve and pedal from the same relaxed standing position, with almost all of my weight on the BB (minimal on the handlebar).

Any longer on the wheelbase, and I'll start looking for a longer CS, unless it also comes with long travel and the dynamic/sagged geo is similar.

FYI, my dimensions are:
Torso/Trunk 61cm
Arm 63cm
Crotch-to-floor/Inseam 80cm

If you want to test such out-of-saddle balance feel at a LBS, perhaps jump onto a:
- med Kona Honzo
- large SC Hardball
- large Niner ROS9

Or, for test fit purposes only:
- med SC 5010
- med Intense Spider 275
- med RM Thunderbolt

Note these sizes only. Since brands don't believe in changing CS according to size, you won't get the same feel in other sizes. If you want an example for something in your size, just get a similar ratio between CS length with wheelbase. This ratio works for me, yours might be a bit different, perhaps 430 with 1150, such as found on the Norco Fluid HT.

How the bike gets the front wheel precisely in this location, is up to preference, but the trend of extending reach+steepening the STA reduces the difference between seated and standing, which is a plus in my book. It might not be others, if they prefer to use different muscle groups, as part of a strategy to extend their range. If you want more stability and comfort, extend the wheelbase and CS. How you extend the front is up to you, whether it's slacking the HA or increasing travel or whatever.

For starters, if you haven't tried already, shorten the CS on your Pivot LES as much as possible, so you don't have to scoot your hips back to pedal with decent traction out of the saddle. Then try to push the front wheel a bit more forward by running less sag. Then try extending it further by increasing fork travel. If you want to keep your angles in check, you can keep the front tire size in check at no larger than 2.3, and perhaps stuffing the tallest tire you can into the rear. Extra stem length likely does the opposite of you want, shifting weight away from the rear.

Review of prior posts: 
- balanced weight distro between wheels is priority
- lengthen CS if you have a problem with the front wheel lifting
- shorten the CS if you have a problem with needing to scoot your body back excessively for traction


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## seat_boy (May 16, 2006)

The best climbing bike I've had (and I've gone through a lot of bikes), was my Jones Plus (now called the LWB). With the manly 19" chainstays, the sweet spot between spinning out and flipping backwards felt like it was about a mile long.

It was also my most confidence inspiring bike on descents, suspended or not...


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## *OneSpeed* (Oct 18, 2013)

seat_boy said:


> The best climbing bike I've had (and I've gone through a lot of bikes), was my Jones Plus (now called the LWB). With the manly 19" chainstays, the sweet spot between spinning out and flipping backwards felt like it was about a mile long.
> 
> It was also my most confidence inspiring bike on descents, suspended or not...


Geared or SS?


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## mack_turtle (Jan 6, 2009)

Also Jones-related: I can never find details on the geometry that apparently makes them so magical. Is it a secret?

Also skeptical of people who ride super long bikes and talk about climbing on them. How TF do you get the front wheel in the air while climbing? Or are you climbing a gravel road?


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## eri (Sep 4, 2012)

This is such a great thread, so much advice I agree with.

Two things:

This custom bike will have adjustable dropouts so you should be able to choose your csl... I have a kona raijin that I love but I ride it with csl slammed whenever possible. Limit is tire and seatstay. I'd want a bike I could at least play with shorter csl meaning bent seat tube. I mean what's the harm? I believe at some point a csl will be too short, but I think my own happy place is maybe 1cm shorter than my beloved raijin.

Watch the top tube clearance and head tube height. With 120mm fork I run a negative rise stem on the raijin. Easy to get a riser stem but impossible to go lower if top tube is in the way.

For reference im 6' with 6' arm span.


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## seat_boy (May 16, 2006)

I ran it both ways.



*OneSpeed* said:


> Geared or SS?


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## seat_boy (May 16, 2006)

Yeah, Jones is frustrating with his geo info. Someday I'll crowdsoure it and publish a blog post about it.

It's certainly doable to get the front end up, but it doesn't flick right up like on my Karate Monkey. Nothing's free.



mack_turtle said:


> Also Jones-related: I can never find details on the geometry that apparently makes them so magical. Is it a secret?
> 
> Also skeptical of people who ride super long bikes and talk about climbing on them. How TF do you get the front wheel in the air while climbing? Or are you climbing a gravel road?


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## mack_turtle (Jan 6, 2009)

I would have to try it, I suppose, but a 29er with a 19" CSL sounds like a torture device. might as well try to loft a Surly Big Dummy over a log on the trail. climbing on something like that would give me lots of stability and traction, until I plow face-first into a small rock that didn't have the courtesy to get out of my way.

Dirt Rag reviewed the Jones Plus thusly:

"The reach is fairly short and the chainstays are long, as in no-I-promise-it's-not-a-typo 19 inches long. However the slack seat angle offsets the chainstay length somewhat as it moves the rider back compared to the ultra-steep seat tubes on a lot of modern bikes."

that sounds fine when you have the option of shifting down to your dinner plate-sized cassette cog in the back and spin away, but when you don't want that option, you need to stand and mash, I would think that would be a liability, unless you're nine feet tall.


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## ninjichor (Jul 12, 2018)

Wouldn't judge the Jones so harshly. It's made for a different kind of rider, one who's definitely not the sporty kind. It's like a recliner, compared to a typical office chair, for very leisurely paced riding. I can imagine bliss just taking in the scenery. Can walk it over logs if you have to. Seems more versatile than an off-road recumbent at least.


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## seat_boy (May 16, 2006)

This makes it sounds like you've never ridden a Jones. It can be ridden slowly, sure, but it's also very stable and confidence inspiring for hard charging.

The weak point for me is very tight trails, where the inertia of the big wheels become apparent. But I find this true of every 29+ bike I've ridden.



ninjichor said:


> Wouldn't judge the Jones so harshly. It's made for a different kind of rider, one who's definitely not the sporty kind. It's like a recliner, compared to a typical office chair, for very leisurely paced riding. I can imagine bliss just taking in the scenery. Can walk it over logs if you have to. Seems more versatile than an off-road recumbent at least.


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## ninjichor (Jul 12, 2018)

This makes it sound like you haven't ridden the Trek Stache 29+ in tight conditions. Does that discredit your post?

When you state stuff like that, you have to give context that makes it comparative to something. There's no stated example, and there's no established standard. Your standard could be a NORBA XC 26" 71/73 HT with 42" wheelbase. Anything with a longer wheelbase is more stable, and modern tires, brakes, and general stoutness of parts offers confidence. 26 geo survived past 2010. Wheels got bigger, and wheelbases got longer due to fitting them in (longer fork at a minimum).

I'm comparing to my experience on Electra Townie style bikes, as they have chainstay lengths that are actually 19", no exaggerating. Close enough to get an idea of Jones Plus, considering this thread is about CS length. The climbing experience is quite different. Best way up is to keep it spinning and never let it get down in RPM, but it surprisingly goes up easily by tightening your grip on the bar and pushing through the pedals from behind. Doesn't feel like I'm forced into an unnatural position--my body just seemingly fell into the ideal position, which is far from feeling as if I'm falling off. I just tense up my arms to enable more power into the pedals, not too differently from how people pull on the bars to get more power down with a more upright position. Rode it where I rode my normal mtbs, but confidence definitely was compromised due to not having quality tires and brakes designed for such riding.

Let's just say I have my doubts that it'll beat any of my PRs on anything that demands technical skills, like others have suggested. Its strength is cruising, well suited for endurance, and how it carries its weight well. I'd dare say that it *can* climb faster, as long as the climb allows you to keep a rhythm (no big interruptions that can upset the pace).


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## seat_boy (May 16, 2006)

I owned a Trek Stache 29+. I didn't really care for it; I much preferred the Jones in pretty much every aspect. But hey, you can extrapolate how a Jones rides because you rode an _Electra Townie Cruiser._ How can I argue against that?



ninjichor said:


> This makes it sound like you haven't ridden the Trek Stache 29+ in tight conditions. Does that discredit your post?
> 
> When you state stuff like that, you have to give context that makes it comparative to something. There's no stated example, and there's no established standard. Your standard could be a NORBA XC 26" 71/73 HT with 42" wheelbase. Anything with a longer wheelbase is more stable, and modern tires, brakes, and general stoutness of parts offers confidence. 26 geo survived past 2010. Wheels got bigger, and wheelbases got longer due to fitting them in (longer fork at a minimum).
> 
> ...


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## eri (Sep 4, 2012)

Every time I read one of these csl discussions there's a bunch of you space aliens out of the woodwork that say that longer chainstays are good, they help climbing traction, etc. I'm totally bewildered by this.

Do we have a different vocabulary? Are people really saying that longer chainstay helps climbing?

One possibility is that we mean something fundamentally different when we talk about climbing. In my case its 1-2k feet of sustained 450-550ft/mile singletrek with loose switchbacks and some step type roots. Quite a bit of my climbing is out of the saddle and my cadence will drop to 30 sometimes. I also need to manual features while climbing.

From my perspective I want the front end to be as poppy as possible without me looping out while climbing. Poppy because I need to get the front wheel over roots and manual more easily. I ride a large Kona Raijin with the rear axle slammed and have never looped out, but I have fallen or failed many times because the rear wheel has lost traction. I'm honestly wishing I could try riding with a shorter chainstay because I still have traction problems in the steeps where I must hang back off the bike to weight the rear.

For me the perfect climbing experience is that front end is light when climbing steeps out of the saddle, and I can easily hoist the front end with a slight rearward motion. I place my bars so theyre natural to hold and reef on while climbing out of saddle, and they don't ever hit my knees.

My Raijin with slammed rear axle has csl of 16.75". I wish it was shorter. Under what conditions would a competent technical rider want a chainstay that was longer than that?

I previously had an early vassago jabberwocky (I think version 2) with 17.7" chainstays and that sucker was hell to ride. Like kept nearly dying because I couldn't manual it to save my life and felt like I was going to bust my gut hanging off the back while climbing steeps (really really couldn't get enough weight over rear wheel). I'll grant that bike was a joy to descend smooth trails - felt like gs skis, but wasn't suitable for the rides I love.

So please can someone that likes long chainstays take the time to explain under what circumstances they are better than a short chainstay?


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## Sage of the Sage (Nov 10, 2011)

When one is 6 1/2 feet tall, longer chainstays can help with weight distribution...


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## mack_turtle (Jan 6, 2009)

A lot of factors come into play when one rider wants a CSL that's longer or shorter. Rider hieght, the reach and stack of the grips relative to rider dimensions, etc. For my proportions and the way I set up and ride my bike, I have not found a "too short" yet.


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## eri (Sep 4, 2012)

Sage of the Sage said:


> When one is 6 1/2 feet tall, longer chainstays can help with weight distribution...


'Weight distribution': can you be more specific? There is some problem with being tall? What bad thing is happening when stays are too short?

You loop out when climbing seated? Guessing here.


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## mack_turtle (Jan 6, 2009)

I rode BMX back in the day and helped a very tall guy build a street/ park bike with 20" wheels. He bought the longest frame on the market, and the front end fit him just fine. The back end, however, was super short, as the trend of the day was such. 

At 5'9", I really liked a sub-14" chainstay on my BMX bike for manuals, hops, and spinning manuevers. The shortest bmx CSL I ever had was about 14" but I wanted something in the 13.5-13.75 range. so it goes.

For him at about 6'4", he had the axle hanging out the back of the dropouts so that he would not loop out onto his back when he did so much as sneezeand it was still too short. He probably would have benfits from an even longer front end or 24" wheels, but the 13.5" or so CSL on that particular BMX bike (I think it was an S&M Tony Cardona signature frame), it was a liability.

I still think that bikes for tall people should have longer chainstays.


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## eri (Sep 4, 2012)

mack_turtle said:


> I rode BMX back in the day and helped a very tall guy build a street/ park bike with 20" wheels. He bought the longest frame on the market, and the front end fit him just fine. The back end, however, was super short, as the trend of the day was such.
> 
> At 5'9", I really liked a sub-14" chainstay on my BMX bike for manuals, hops, and spinning manuevers. The shortest bmx CSL I ever had was about 14" but I wanted something in the 13.5-13.75 range. so it goes.
> 
> ...


Ok, so problem with seated riding? For standing I don't believe it, for example unicycle.

For seated riding... is the problem with seat location? Could that be fixed with a more vertical seattube? Or a triathlete seatpost?


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## geraldooka (Jul 3, 2012)

eri said:


> So please can someone that likes long chainstays take the time to explain under what circumstances they are better than a short chainstay?


Perhaps where someone's circumstances are different than yours?

Arguing about which geometry is better is one of the longest running asinine activities that takes place on bike forums.

You like short, some like long. Some like low some like tall. There is no right or wrong.


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## eri (Sep 4, 2012)

geraldooka said:


> Perhaps where someone's circumstances are different than yours?
> 
> Arguing about which geometry is better is one of the longest running asinine activities that takes place on bike forums.
> 
> You like short, some like long. Some like low some like tall. There is no right or wrong.


I'm totally open to alternate tastes. But this longer chainstay presence reads to me like 1+2=4. It reads wrong to me and I'd like to understand my misunderstanding, Is a big world.

Don't see why we can't discuss like friendly enthusiasts.


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## ninjichor (Jul 12, 2018)

What longer chainstay "presence" reads like 1+2=4? Sounds like your imagination getting in the way. 

Perhaps the Jones Plus hype presented earlier is causing confusion. If this is not the case, skip to the next paragraph. Someone stated that it'd suck because they couldn't lift it over a log. I understand that if you struggled to get over logs with shorter CS bikes, the longer one is not going to help that. If you already are good at it, it'll take a bit of adjustment. I added that if you're already a shredder, you can shred on the Jones Plus too. That guy wanted something to help him get over logs, so it's disqualified for *him*. Someone chimed in with hype, to save the Jones from wild imaginations. It's a case of things being more about the rider, than being about the bike. The bike does certain things good, and if your "95%" fits the bike's, you're golden, but don't think it's totally incapable of that 5% if the rider wants to do it; it's just less optimized for it.

Who the hell loops out when climbing? xD Maybe people are saying that the front wanders due to lacking weight, and if your bike goes off-course due to the front wheel not touching the ground, and cannot recover from it, you likely have to put a foot down. It happens most when you're putting out high torque at low speed, especially with very low gearing. Those that prefer low gearing would like longer chainstays. I don't know who runs anything lower than 32x22 on a singlespeed, but I'm not going to rule out their existence.

What's a friendly enthusiast and why would they come here to discuss? What's an alternate taste? Your expectations and bias seem are skewing your views maybe. I imagine people come here to pass the time because they're bored, want to learn, and/or have some urge to F with other people (to vent frustrations). It's like a hang out where you can speak your mind. Generally, you should try and deciper things, else you end up being picked on like Picard.


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## *OneSpeed* (Oct 18, 2013)

Sage of the Sage said:


> When one is 6 1/2 feet tall, longer chainstays can help with weight distribution...


I'm 6'3" and I've never ridden a bike and thought the chainstays were too short. Including a few in the 415mm range.

I don't entirely disagree (in theory) that bigger frames can/should have slightly longer chainstays if the goal is to have frames handle the same across the size range, but the difference in chainstay length should only be a few MM, not a few CM. It's also not the only factor that should be considered.


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## mack_turtle (Jan 6, 2009)

eri said:


> Ok, so problem with seated riding? For standing I don't believe it, for example unicycle.


Just to be clear, no one sits on a BMX bike while riding. They have the saddle about an inch above the top tube, usually below the rider's knees when standing. if one we're to put a seatpost on such a bike that is long enough to sit and pedal, the saddle would put your CoG directly above or even behind the rear axle.

As for seated riding. I suspect that riders who utilize a more upright position with a taller handlebar and shorter overall reach (which BMX bikes also have) means that shifting weight back is so easy that it makes the bike tippy, so a longer CSL is preferable to stabilize it.

That might be what makes the idea so polarizing. I'd be curious, but not curious enough to do all the work of gathering such data, to compare the heights, effective reach and stacks (measurements from BB to grips) and CLS of many riders. My suspicion is that if you have a long, low bike relative to your height, you'd prefer a short CLS. People who set their bikes up more tall/ short reach would prefer a longer CSL.


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## eri (Sep 4, 2012)

ninjichor said:


> What longer chainstay "presence" reads like 1+2=4? Sounds like your imagination getting in the way.


Well... I'm having trouble with the basic concept that a longer stay will provide more traction for climbing: Does Not Compute. I can see longer stays helping with other stuff, like front/rear balance when cornering, and it could prevent looping in some really extreme case I suppose.



ninjichor said:


> Who the hell loops out when climbing? xD


I dunno, uh, people that haven't ridden a bike before? Try and climb steeps seated in granny gear and don't unweight the front over roots? I can't make sense of the claim that longer chainstays help with climbing, am trying to guess what might be the actual 'badness' that they cause. Maybe someone confused 'traction' with 'inability to climb steeps'. Again I don't understand so fishing for facts. It might be there's some other terrain or riding style that I've not heard of, I dunno.

This 'long chainstays help climbing' is something that keeps coming up here, and the discussion never goes anywhere, I think due to lack of specifics.



ninjichor said:


> Maybe people are saying that the front wanders due to lacking weight, and if your bike goes off-course due to the front wheel not touching the ground, and cannot recover from it, you likely have to put a foot down. It happens most when you're putting out high torque at low speed, especially with very low gearing. Those that prefer low gearing would like longer chainstays. I don't know who runs anything lower than 32x22 on a singlespeed, but I'm not going to rule out their existence.


Could be. I'd like someone to step up and describe the problem symptom.

I personally agree about lower than 32x22. I tried 32x23 once (new crank, no 22 cog) and was surprised that my technical climbing was more difficult, I couldn't get enough speed in places where I sprint and bunny hop up.

With 'too-low' gearing it is even easier to overload the rear traction, the rear weighting is just as important and short csl should still be better than long, at least thats what my mental model says.


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## Suns_PSD (Dec 13, 2013)

adinpapa said:


> @ninjochor, thanks for your contributions- helpful. I've read Walt's crank stories. I"d be willing to try a 170 , but I just invested in an eeWing 175mm (after breaking 2x Nexts SL, one that put me out of a race battling for first ,five hours in) ... I'll be sticking with 175 , hopefully for a very long time.
> It will be interesting if shorter cranks catch on. Personally, I think my Pivot LES (M) has an ideal BB height for me and will likely be going with that... it drives the corners with very occasionally pedal strikes.


OT: Any input you can share about the eewings? Was considering a set.

Is the reduced flex noticeable/ beneficial?

Thx

Sent from my SM-G892A using Tapatalk


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## alexbn921 (Mar 31, 2009)

For single speed climbing the shortest possible stays are preferred. They will always give you more traction while standing.
For geared seated climbing CSL needs to be balanced with your height.

General handling needs a balanced ratio front to rear. This is different for every rider and is based on height, body position, build, flexibility and bike geometry. Not an easy target to nail down.

If your extremely tall then short CSL fubars the handling of a bike and limits the handlebar height. Again this will have a wide variance.


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## mack_turtle (Jan 6, 2009)

partially connected thoughts:

I asked Waltworks Walt about this and I am trying to piece together what it means for me. he said that you can make a bike that is easy to lift the front end and get off the ground by:

1. shorter chainstays
2. higher BB
3. shorter reach- get the bars higher or closer to you.

I am not sure if there is a direct correlation between this and rear wheel traction, but it seems reasonable. only #3 can be meaningfully changed on an existing frame without advanced-level modification. you can do so by getting your handlebar higher, using a bar with more setback (result of the bend and width of the bar), a shorter stem, or some combination of those three.

it seems that moving the dimensions of the bike one direction or another makes it "flickable" or "stable." if you wanted a super-stable bike, you'd drop the BB as low as possible, stretch out the front end (could be done with some combination of reach and the resulting front-center measurement), and stretch out the chainstays. maybe Jones is a good example of this. this is probably great for a bikebacking bike. it would carry momentum like a loaded freight train but steer with similar grace. if you built a bike with a high BB, shorter CS, and a short reach, it would be squirrelly in all the right ways, and the wrong ways too.

the trick is finding the right combination for your riding style, body dimensions, and terrain. singlespeeders and hardtail or rigid riders need to make some considerations that others do not to find the balance. Walt built a bike with a ridiculously short CS and short reach/ tall stack front end, but you'll notice he made the BB extremely low -90 mm with 29+ tires) and compensated for that with super short cranks.

for a while there, i was convinced that I wanted a more flickable bike, so wanted a frame with a high BB, of which there are a few on the market. however, those high-BB frames usually have longer chainstays- why can't I have both? I think frame designers are aware of this relationship and avoid building bikes with both a high BB and a short CS, knowing that the two features probably balance one another out perfectly at some point for the right rider.

so a low BB probably ought to go with a short chainstay, and a high BB ought to go with a longer CS?


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## *OneSpeed* (Oct 18, 2013)

mack_turtle said:


> if you built a bike with a high BB, shorter CS, and a short reach, it would be squirrelly in all the right ways, and the wrong ways too.


Hard to argue with this kind of logic. You have both sides covered. :skep:



> so a low BB probably ought to go with a short chainstay, and a high BB ought to go with a longer CS?


Yup.

Here's some interesting old school geo that defies modern logic. Talk about a high BB, it's 2-3 inches above the axles. Plus a nice short reach.

https://www.pinkbike.com/news/bike-check-brodies-2002-8-ball-incremental-improvement.html


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## seat_boy (May 16, 2006)

The neat thing about Jones geo is that they achieve the long front center with an extra long rake on the fork (76mm), but with a relatively short reach to the bars (shorter top tube) and bars that sweep back. So there's one clue how he can achieve a relatively nimble bike with 19" chainstays. It handles nothing like a "loaded freight train."

But they key thing here is you can't look at one number in isolation and predict how a bike will handle.



mack_turtle said:


> partially connected thoughts:
> 
> I asked Waltworks Walt about this and I am trying to piece together what it means for me. he said that you can make a bike that is easy to lift the front end and get off the ground by:
> 
> ...


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## *OneSpeed* (Oct 18, 2013)

seat_boy said:


> But they key thing here is you can't look at one number in isolation and predict how a bike will handle.


So true. The "extreme" nature of a Jones bike exemplifies that. It's so weird, and somehow most people that ride one seem to like it.

In my (inexperienced at frame building) mind it goes against what I think is fun about a bike. It's not possible that this weird combination of geometry numbers could be fun to ride, yet I would love to ride one myself and form my own opinion because I've been proven wrong before. (that said, I'm only curious and have no desire to own one)

Aside from not singling out any one number, numbers on a geometry chart don't always add up to real life impressions on a trail. You have to consider the bigger picture.


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## Sage of the Sage (Nov 10, 2011)

eri said:


> 'Weight distribution': can you be more specific? There is some problem with being tall? What bad thing is happening when stays are too short?
> 
> You loop out when climbing seated? Guessing here.


Yup. My Timberjack has the stays set at the midpoint with the alternator dropouts, and I still occasionally loop out on techy climbs, seated or standing.


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## adinpapa (Dec 4, 2007)

delete


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## adinpapa (Dec 4, 2007)

Suns_PSD said:


> OT: Any input you can share about the eewings? Was considering a set.
> 
> Is the reduced flex noticeable/ beneficial?
> 
> ...


sorry for the delay on this... re eeWings experience
Yes, noticeable stiffness over NEXT SLs. They do drive more power/expected response from my Pivot LES . I chuckle when I smash them on rocks. Can't wait to get them on a proper ti frame (aesthetics mostly) . I wouldn't pay msrp , but for what I got them at, I'd buy them again. Those new XTRs are looking nice though,,,


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## Suns_PSD (Dec 13, 2013)

adinpapa said:


> sorry for the delay on this... re eeWings experience
> Yes, noticeable stiffness over NEXT SLs. They do drive more power/expected response from my Pivot LES . I chuckle when I smash them on rocks. Can't wait to get them on a proper ti frame (aesthetics mostly) . I wouldn't pay msrp , but for what I got them at, I'd buy them again. Those new XTRs are looking nice though,,,


Thanks. I bought a set. Nice cranks.

Sent from my SM-G892A using Tapatalk


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## carabao (Apr 25, 2006)

eri said:


> Every time I read one of these csl discussions there's a bunch of you space aliens out of the woodwork that say that longer chainstays are good, they help climbing traction, etc. I'm totally bewildered by this.
> 
> Do we have a different vocabulary? Are people really saying that longer chainstay helps climbing?
> 
> ...


You NEED a Kona Honzo. I only climb out of the saddle and by the description on how you ride I know you would love it.


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## mack_turtle (Jan 6, 2009)

There are other frames that have very short chainstays besides the Honzo. Like any other popular bike, Honzo riders have a religious zeal for them for some reason. The Honzo has a low BB and a VERY long reach, which one might find a bit cumbersome in some situations. Personally, I could not ride a Honzo uness I sized down and used a crazy-long seatpost in addition to a very short stem for the way I like bikes to fit.


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## ninjichor (Jul 12, 2018)

You can have chainstays too short and chainstays too long. It all depends on how the rider's weight is balanced between the front and rear wheel.

If you have chainstays too short, they are more sensitive to losing traction on bumps and the front will be hard to control. You tend to be forced to shift your weight forward on the tip of the saddle.

If you have chainstays too long, they are more sensitive to losing traction if you ride out-of-the-saddle with a forward pedaling position. You tend to be forced to spin in the saddle.

There's no magic number. 435mm can be too long on one bike and too short on another, since weight balance depends on how long the front of the bike is too. It's more like a magic ratio.

I estimate the sweet spot to be about 435mm CS with a 1225mm wheelbase, for the neutral standing/pedaling position. Add/subtract ~25mm of wheelbase for every 5mm of chainstay difference. Add 3mm to wheelbase for every 20mm of travel over 100mm (4mm for hardtail).
- 420mm CS feels balanced with a 1150mm wheelbase
- 450mm CS feels balanced with a 1300mm wheelbase

- 420mm CS with a 1200mm wheelbase will be too rearward-biased, and the front will tend to lift and wander on climbs. The bike will also feel nervous, lacking confidence, on the descents, unless you learn to purposely weight the front. The front will be prone to washing out in corners. The rear wheel will take a heavier-than-normal beating from plowing over impacts. This is one case where downsizing to a smaller size will help.

- 435mm CS with a 1175mm wheelbase will be too forward-biased, and the front will tend to dive on jumps/drops, and the rear will tend to lose traction when hammering out of the saddle. The bike will feel a bit stable and secure in corners and descents, but you will be bad at gaining air without accustomizing yourself to the bike and the specific drops/jumps. This is one case where extending fork travel and/or upsizing will help.

This fore-aft weight balance ratio is hugely important. It surprises me that people don't pay more attention to it, despite feeling clear differences between two sizes of the same bike ridden back-to-back. If you have a quirky weight bias, you have to compensate by shifting your body's CoG to where it will give the bike better balance--holding that position takes effort and you have to be able to initiate techniques from that position, which may be more difficult. Proper fit should make it so you are in the balanced sweet spot when you are relaxed, and have ample freedom to move around in any direction.


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## eri (Sep 4, 2012)

ninjichor said:


> You can have chainstays too short and chainstays too long. It all depends on how the rider's weight is balanced between the front and rear wheel.
> 
> If you have chainstays too short, they are more sensitive to losing traction on bumps and the front will be hard to control. You tend to be forced to shift your weight forward on the tip of the saddle.
> 
> ...


Wow... nice essay. I think what you are saying about balance generally rings true to me. Not sure about the precise numbers you've listed though, I still wish my raijin had shorter stays, mine rides at about 1120 wb and 430csl, also the equation needs to consider reach and bar height too... my bike is happiest with a 90mm stem, shorter and longer are bad-er, and bb height also has a huge impact...

Given this is the singlespeed forum I've assumed that one is always out of the saddle when traction limited. You'd need to be quite undergeared if you were seated climbing the steepest trails... Always? Yes?

I tried a geared honzo cr, size large with a Fox 36. Just 30 minute ride. It felt cumbersome to me, the front felt very long, I had to move far forward to keep the front wheel properly weighted. It's a very capable descender and grip was awesome for climbing. But at the end I was happy to get back on my raijin - it has some magic for me, or I'm just crotchety and close minded.


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## *OneSpeed* (Oct 18, 2013)

ninjichor said:


> You can have chainstays too short and chainstays too long. It all depends on how the rider's weight is balanced between the front and rear wheel.
> 
> If you have chainstays too short, they are more sensitive to losing traction on bumps and the front will be hard to control. You tend to be forced to shift your weight forward on the tip of the saddle.
> 
> ...


You realize this is the SS forum and the conversation is specifically about SS's. Nothing about your post is SS related. Are you talking about a SS? Do you ride a SS?


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## azjonboy (Dec 21, 2006)

Adinpapa - have you figured out what you’re going to do?

Personally, I had 2 Pivot Les. Rode them geared as I have a Black Sheep SS 29+
I found the Les maddeningly light in the front end when climbing loose, techy stuff. The bottom bracket was also very low, I think mine measured out at 11.75” in 29er mode. I ran the Les 27.5+ x 2.8 and 29x2.4. It rode better in 29” mode IMHO as the BB was raised a touch, but even then I still had to really think ahead to avoid pedal strikes. 

The only reason I had 2 of the Les is the first one suffered a cracked BB shell after a few months so they replaced it at no charge with another.

The Pivot was well made and specced, and had a nice feel, but the low BB and light front end killed the deal for me, so I sold it.


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