# Seeking opinions on the trend towards steeper seat tube angles



## golden boy (Oct 29, 2008)

Especially as it relates to hardtail bikes. Sure, it makes for good copy when the big manufacturers rave about how their steeper seat tube angle aids in climbing the steep stuff, but what about all other terrain? To be blunt, I'm skeptical. But then again, that's my nature with most new trends in MTB. It took me a long time to come around to dropper seatposts, but now I'm completely on board.

So, especially amongst the experienced builders out there on this forum, what are your thoughts on seat tube angles in the 76/77 degree range? I can't see (without riding one) how this could possibly be a good all-around setup.

EDIT: I should add that my most recent personal frame build inadvertently ended up with a seat tube angle of approximately 71 degrees. I say "approximately" because the seat tube is bent so it's hard to get an exact measurement off of the bike. If you believe the current hype, you would think this bike would be unrideable. But I love it, and I only ever notice the slack seat angle on the steepest of climbs. In all other terrain it feels great.


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## cassieno (Apr 28, 2011)

My experience (3-4 different frames with different SA). Steep terrain is better suited to steep SA. 

Flatter I don't want as steep because it may not be as comfortable (too much pressure on my hands).

However, bikes are a system and chainstay length, reach, handlebar position etc etc all play a role and it's hard to break bikes down to 1 angle.

Your experience with a "slacker" seat angle actually matches what we (Little_Twin) and I have discovered recently. He built a bike that should be terrible (per the internet), but it feels really good) And, you can counteract that slack SA by having longer (440 instead of 420) chainstays. 

Note, I am not an experienced frame builder but have been riding a variety of frames with different SA, thinking about how it feels, and then having the next one built with a change for a specific reason. 

So, just supporting your "I am skeptical statement." I think that's a reasonable place to be.


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## pvd (Jan 4, 2006)

If you live where it is flatter, steep seat angles are terrible. Basically, anywhere where you have a lot of traversing. I live in the SF bay area and ride the real stuff. I tend toward a 74.5 to 75 degree effective seat angle on a hardtail. On a full suspension, 76 to 76.5 degrees.

Manufacturers are doing them more everywhere as it makes bike manufacturing easier and cheaper.


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## golden boy (Oct 29, 2008)

I hear you guys on how the terrain that you ride matters. And Peter I agree that hardtails should dial it back a bit since the head angle can only ever get steeper, unlike full-sus bikes.

But don't we all ride trails that have flat spots, rollers, and steeps? Anyway, I'm looking for a good all-purpose frame geometry, realizing that it won't excel in all terrain.


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## Erichimedes (Jul 30, 2010)

I see this dimension being one of the most subjective to where you ride, and how you ride.

If you want to over-simplify it: Steep angles are better for steep climbing, slack angles are better for slack riding.

If you want to get into everything else that is also involved, then don't forget: does the rider climb hills mostly out of the saddle? Does the rider have a lot of traversing terrain? Do they have a dropper post? Are they on a singlespeed? All of those things factor in.

Yes, there is variation in any of the terrain we ride, but that affects everything. We just try to average out what works the best in the most scenarios for us, and go from there.

The Industry likes to tout every new feature or geometry change as being the best for everyone, but obviously that doesn't make sense. But The Industry is used to catering to consumers who for the most part know very little about the product they're buying. So they just say, "buy this, it works great" and most customers do.


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## TimTucker (Nov 9, 2011)

On the "how you ride" side of things, foot positioning seems to be an often ignored factor for what's "optimal" for STA.

Because your feet wind up further forward relative to the seat, midfoot pedal positioning can make a bike feel like the seat angle is slacker than the numbers would suggest.


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## scar4me (May 16, 2010)

Thought I'd add my input here too....

As mentioned steeper is not always better.
If you don't change anything else, then steeper actually cramps up the cockpit of the bike very quickly.
I build my bamboo frame with an 80deg STA. (planned 79deg, but the jig settled at 80 and I ran with it).
Most of my riding is not super steep climbs or descents, its mostly relatively flat trails.
Since my reach was 500mm, it actually has a similar cockpit feel to my old alloy frame when saddle up and climbing.
The biggest difference I find is that your body position CoG is more forward and less upright, since the BB is further back under you and your hips are rotated forward slightly due to this.
Some people would hate this feeling, but where I ride mid-foot pedal position with flats it actually suits me better.
It gets very close to personal ergonomics at this point, as certain people have preferred lower back/hip angles that they prefer and find most comfortable to ride with. Saddle angle can assist/help this slightly, but not as much as you might think, as most of the body weight is actually going through the 2 sit bone pressure points.

Yes, when riding along the flats this more forward position does have the negative effect or more bodyweight through your bars\arms.
This is where compromises and personal preference should always prevail over "the latest" trends. And is also why most new geo reviews out there will state that it really rewards an aggressive rider. (read that as not the best for all round riding  )

Where the bike does shine is when things get faster, and steeper. So it does push me to ride a bit more aggressively. And this is what a lot of reviews of frames I took the inspiration for the geo from said. Climbing, it's really nice to be more forwards with the body position. Descending it's great when it speeds up, but can be a handful when it gets slow, steep and technical.

Octane One prone 29er L, running 160mm fork and 27.5 wheels, with 72deg STA, and 440mm reach was my comparison frame if anyone's interested.

My experience has also taught me that yes you can go too far, and I went slightly over.
As much as my bamboo bike is a nice ride, it is a bit stretched out for general riding and due to the long reach takes a lot more body language to get the front wheel up.
So even though the cockpit feels nice, it isn't as evenly balanced for slower playful riding as my alloy frame is.

The key measurements to note when looking at actual bike fit are: 
1: saddle to grips (at climbing height)
2: BB to Grips 
3: hip angle
Hip angle is the one that is dependant on personal measurements, torso length, and arm length. And also crank length, and leg proportions.
There are a lot of bike ergonomics studys you can find regarding road, but not that many about for MTB.

So horses for courses, take inspiration from other frames geometry. But do read the reviews and you should be able to take a rough judgement and find something that is right for you.


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## dsut4392 (Mar 9, 2007)

golden boy said:


> Especially as it relates to hardtail bikes. Sure, it makes for good copy when the big manufacturers rave about how their steeper seat tube angle aids in climbing the steep stuff, but what about all other terrain? To be blunt, I'm skeptical. But then again, that's my nature with most new trends in MTB. It took me a long time to come around to dropper seatposts, but now I'm completely on board.


I'm a rider who has lived through the last 30 years of MTB development, still own my 1990 hardtail alongside a 2020 'Enduro' full suspension bike. Looking at STA in isolation from chain stay length, reach and stack is just a nonsense, regardless of the terrain/riding style the bike is designed for. Change any one number and you have to change many others to end up with a bike that rides nicely. 
The steeper STA lets you lengthen the wheelbase while keeping your seated weight centred, so you can weight your front wheel through corners despite the HTA being slacked out. Because you have lengthened the wheelbase, the bike is also a more confident descender.


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## drdre (Dec 15, 2005)

I'm not a frame builder but I can tell you that my l45 disk is disintegrating and my bike with 77 sta helps it and my bike with 74 probably actually hurts it.


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## Jukka4130 (Jun 21, 2020)

An experiment with steep seat tube angles on a recent gravel project proved to be a winner. Works just as nicely as it does In mountain bikes.


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## TimTucker (Nov 9, 2011)

Jukka4130 said:


> An experiment with steep seat tube angles on a recent gravel project proved to be a winner. Works just as nicely as it does In mountain bikes.


I'm curious -- what's the geometry on that / how steep did you go?


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## Jukka4130 (Jun 21, 2020)

67° head angle, 78.5° seat angle, 465mm reach and 439mm CS length.


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## kendunn (Sep 9, 2013)

The only downside to steep seat angles is they can make the bikes feel cramped. Bikes have gotten much longer, thus making steeper seats possible. I just bought the wife a Mt Bromo and love the fact that my knees get out in front of the pedals more. I just ordered a new 951 Trail, actually kinda wanted the less travel of the XC, but didn't like how far back the seat was.


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## Jayem (Jul 16, 2005)

pvd said:


> If you live where it is flatter, steep seat angles are terrible. Basically, anywhere where you have a lot of traversing. I live in the SF bay area and ride the real stuff. I tend toward a 74.5 to 75 degree effective seat angle on a hardtail. On a full suspension, 76 to 76.5 degrees.
> 
> Manufacturers are doing them more everywhere as it makes bike manufacturing easier and cheaper.


I agree with this. It's typically a shorter travel bike to hardtail where this is an issue, where you are on level ground for most of your ride. The longer you are on level ground, the worse this is.


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## Jayem (Jul 16, 2005)

kendunn said:


> The only downside to steep seat angles is they can make the bikes feel cramped. Bikes have gotten much longer, thus making steeper seats possible. I just bought the wife a Mt Bromo and love the fact that my knees get out in front of the pedals more. I just ordered a new 951 Trail, actually kinda wanted the less travel of the XC, but didn't like how far back the seat was.


No, the other downside is the excess pressure on your wrists.


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## kendunn (Sep 9, 2013)

Jayem said:


> No, the other downside is the excess pressure on your wrists.


Which is from being cramped up


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## cassieno (Apr 28, 2011)

The other downside is patella knee pain. But I get along all right with 75 on a hardtail for the ups and downs. For the more level I like something closer to 73.5.

And no I don't get excess pressure on my wrists from being cramped. I can be cramped and not have excess pressure. Excess pressure is SA / torso angle interaction. It varies from each person.


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## Jayem (Jul 16, 2005)

cassieno said:


> The other downside is patella knee pain. But I get along all right with 75 on a hardtail for the ups and downs. For the more level I like something closer to 73.5.
> 
> And no I don't get excess pressure on my wrists from being cramped. I can be cramped and not have excess pressure. Excess pressure is SA / torso angle interaction. It varies from each person.


Yeah, you aren't changing the distance if you rotate the rider clockwise...but you end up with more pressure forward.


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## D.F.L. (Jan 3, 2004)

Soon enough, your seat angle will automatically adjust based on GPS location and terrain angle. If the tech allows it. It'll probably happen.


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## TimTucker (Nov 9, 2011)

D.F.L. said:


> Soon enough, your seat angle will automatically adjust based on GPS location and terrain angle. If the tech allows it. It'll probably happen.


Colin Furze was halfway there with dynamic adjustable geometry - just need to combine that with GPS:


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## vikb (Sep 7, 2008)

For a HT ~74 deg unsagged STA works for me with a ~140-150mm fork.. I don't need a steep STA for climbs. I can just slide forward on the saddle for the short periods of time that are needed.


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## Dedo verde (Dec 20, 2021)

hi folks, i think a lot about steep seat tube angle and when i crashed my last bike i order a custom frame with 77º on ST angle and 70° on the head and, for me, its works veeeeery nice!

someone did anything similar?


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## VegasSingleSpeed (May 5, 2005)

The setback on that seatpost, and having your saddle adjusted about as far rearward as it'll go, offsets the steep seattube angle. That's like having a 74 or 75-degree seat-tube with a 'normal', low-offset seatpost.


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## dr.welby (Jan 6, 2004)

Dedo verde said:


> hi folks, i think a lot about steep seat tube angle and when i crashed my last bike i order a custom frame with 77º on ST angle and 70° on the head and, for me, its works veeeeery nice!


Look for scans of two Bicycle Guide magazine articles from 80s/90s:

Alexi Grewal's Clark Kent AX-1 Bike Forums - View Single Post - 30 Years Ago: December 1990 in Bicycling magazine

Roosa Project / Quintana Roo review :

__
http://instagr.am/p/BjddTjwB3KA/
 and

__
http://instagr.am/p/BjgFbe5h_dy/


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## Dedo verde (Dec 20, 2021)

dr.welby said:


> Look for scans of two Bicycle Guide magazine articles from 80s/90s:
> 
> Alexi Grewal's Clark Kent AX-1 Bike Forums - View Single Post - 30 Years Ago: December 1990 in Bicycling magazine
> 
> ...



nice bikes, tks for share it

i realized its not any inovation since i start to think about, but i´m so begginer in this bike world and, 
even though i didnt find any gravel bike whith steep st, its not my inovation, 
the reason for adopted this is in order to shorten CS and still fit big tires(47mm in my bike) and, its alow to make a small frame as possible and, because of it, more stiffer i guess

sorry about talk too much, im a lonely rider =P


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## XC Only (Jul 9, 2007)

pvd said:


> If you live where it is flatter, steep seat angles are terrible. Basically, anywhere where you have a lot of traversing. I live in the SF bay area and ride the real stuff. I tend toward a 74.5 to 75 degree effective seat angle on a hardtail. On a full suspension, 76 to 76.5 degrees.
> 
> Manufacturers are doing them more everywhere as it makes bike manufacturing easier and cheaper.


I'm in the Bay Area as well, and I'm with you on the steep seat angles, 76 degrees is what is on the Kona Honzo now, and I think it is a tad steep--75 degrees would be ideal for me. I'm originally from the East Coast and moved to SF in 2004, which might as well be considered the dark ages in terms of mountain bike technology, but I distinctly recall needing to get the zero offset seatpost and scooting the saddle forward as well as getting a 120mm stem to deal with the steeper, more sustained climbing here. Changes which if I could magically conjure up the bike I had then and measure it would probably give an effective ST of 73 to 74 degrees.

I recently took the Honzo up to Bend, OR, and on that kind of terrain, I constantly wanted to, and eventually did scoot the saddle back all the way--relatively flat/rolling with lots of pedaling.

On a side note, as a part-time industrial designer, I find it fascinating looking at how mountain bikes have changed, and to assume the consumer is somehow forced a product is only somewhat true. Take the previous comment regarding flat pedals and it's relationship to seat tube angles. It's a feedback loop, where the end-user definitely "likes" something, but can't quite say _why_ they like it. Could the reason be that someone likes a steeper seat tube angle be because of steeper terrain, or because they have switched to flat pedals and ride that style pedal more? The answer may be both.


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## eri (Sep 4, 2012)

I'm not really sure whats going on here. When its steep climbing I'm not sitting so want the seat back out of the way, and steep descents I want the seat dropped so I don't care there either.

When its not steep and I'm sitting and driving I want to be balanced over the bike with my legs supporting my weight, so I still don't want the seat jammed forward. I've got a honzo and I'd say my seat 'center' is back 3/4" from the axis of the seat tube, its fine. I could jam it forward quite a bit if I wanted, which emulates a steep seat tube but no thanks!


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## cassieno (Apr 28, 2011)

eri said:


> I'm not really sure whats going on here. When its steep climbing I'm not sitting so want the seat back out of the way, and steep descents I want the seat dropped so I don't care there either.
> 
> When its not steep and I'm sitting and driving I want to be balanced over the bike with my legs supporting my weight, so I still don't want the seat jammed forward. I've got a honzo and I'd say my seat 'center' is back 3/4" from the axis of the seat tube, its fine. I could jam it forward quite a bit if I wanted, which emulates a steep seat tube but no thanks!


I am confused. Do you not have 30+ min steep climbs? I cannot stand for .5-1 hour climbing steep loose surfaces while the back wheel skips and slides everywhere. Sure short sections sometimes standing is the way to climb. But, over miles and miles of steep consistent climbs you have to sit and focus on keeping traction to the rear wheel. 

Appropriately steep STAs help with that. Note - Appropriately steep for me is somewhere in the realm of 74-75 degrees. Closer to 74 for an all day all terrain bike. Even less steep on anything that sees huge mileage (gravel bike) on tamer terrain.

STA to me is very very terrain and bike dependent. The STA I want for climbing mountains is different for long flat rides (I get around this by not doing long flat rides)


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## eri (Sep 4, 2012)

cassieno said:


> I am confused. Do you not have 30+ min steep climbs? I cannot stand for .5-1 hour climbing steep loose surfaces while the back wheel skips and slides everywhere. Sure short sections sometimes standing is the way to climb. But, over miles and miles of steep consistent climbs you have to sit and focus on keeping traction to the rear wheel.
> 
> Appropriately steep STAs help with that. Note - Appropriately steep for me is somewhere in the realm of 74-75 degrees. Closer to 74 for an all day all terrain bike. Even less steep on anything that sees huge mileage (gravel bike) on tamer terrain.
> 
> STA to me is very very terrain and bike dependent. The STA I want for climbing mountains is different for long flat rides (I get around this by not doing long flat rides)


yes, for me 30-45 ish is about it for continuous steep, average rides around here are 300-450 ft per mile, but its natural terrain so its only max effort oh no ‘steep’ for up to about 50 ft at a time. Fwiw im still mostly on singlespeed. Theres a fire road here that is more than 75 minutes nearly continuous out of saddle, but i cant think of a natural trail thafs so continuous.

funny you mention dicy grip, is the slippy areas that are best served out of saddle: out of saddle ive got all my weight on back wheel for grip, and can lunge to clear steps. Cant sit when its loose or slippy, back wheel needs weight for grip.

But my ‘not steep sta’ bikes are 74-74.5… sounds like we are vigorously agreeing. There are steeper sta bikes and i just dont see the charm, i think its an error.


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## louiesquared (6 mo ago)

My preference for a steep or slack STA really depends on the reach and stack. Changing just one of those measurements can greatly affect a bike.


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## Hrodulf (12 mo ago)

Switched hardtails recently and went up from a 73.5 STA to a 75 STA and I love it. 

Climbing goes way more relaxed, especially steep climbs or climbs with obstacles. Would I recommend it to a friend ? Yes you bet !


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## eri (Sep 4, 2012)

louiesquared said:


> My preference for a steep or slack STA really depends on the reach and stack. Changing just one of those measurements can greatly affect a bike.





Hrodulf said:


> Switched hardtails recently and went up from a 73.5 STA to a 75 STA and I love it.
> 
> Climbing goes way more relaxed, especially steep climbs or climbs with obstacles. Would I recommend it to a friend ? Yes you bet !


Hey so... I feel like I've always been able to put my seat where I want it, regardless of sta. You get a few inches of forward/back choice for seat position. A degree of sta gives me approximately 1/2" of saddle motion.

Instead of crediting sta, why not just say you like your saddle more forward?


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## XC Only (Jul 9, 2007)

eri said:


> Hey so... I feel like I've always been able to put my seat where I want it, regardless of sta. You get a few inches of forward/back choice for seat position. A degree of sta gives me approximately 1/2" of saddle motion.
> 
> Instead of crediting sta, why not just say you like your saddle more forward?


Regarding where the saddle is in relation to the bottom bracket, that is true. What's different though is that bikes that come with steep seat angles today ALSO have longer reaches to compensate (among other things)--so it may be the combination of the 2 or more that make a particular rider like a bike, and all they attribute it too is "steep seat angle."

Generally speaking, even those un-initiated or don't care to dissect technical details feel that on today's bikes, they feel like they are more stable and sit "in-between" the wheels instead of "on top" of them. That's a combination of longer wheelbases as a result of slack head angles, long reaches, long chainstays.


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## dysfunction (Aug 15, 2009)

At over 6', I dig no longer sitting behind the rear axle.


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## louiesquared (6 mo ago)

eri said:


> Hey so... I feel like I've always been able to put my seat where I want it, regardless of sta. You get a few inches of forward/back choice for seat position. A degree of sta gives me approximately 1/2" of saddle motion.
> 
> Instead of crediting sta, why not just say you like your saddle more forward?


I am right on the edge of medium/large with most bikes and I prefer to size down. This means that I have my seat pretty high. A slacker seat tube will push the seat further back as you raise it up. Depending on how high the seat is and how slack the seat tube is, sometimes moving the seat forward is not enough.


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## eri (Sep 4, 2012)

XC Only said:


> Regarding where the saddle is in relation to the bottom bracket, that is true. What's different though is that bikes that come with steep seat angles today ALSO have longer reaches to compensate (among other things)--so it may be the combination of the 2 or more that make a particular rider like a bike, and all they attribute it too is "steep seat angle."
> 
> Generally speaking, even those un-initiated or don't care to dissect technical details feel that on today's bikes, they feel like they are more stable and sit "in-between" the wheels instead of "on top" of them. That's a combination of longer wheelbases as a result of slack head angles, long reaches, long chainstays.


Ok.

1 place hands where you want relative to head tube.
2 Now select frame with reach that makes you happy standing (rad, relative to bb center and bar width)
3 Finally position seat where you need it for seated comfort.

Boom, done. If above can be achieved the frame fits, otherwise… it doesnt.

4 decide if you are happy with csl and front wheel placement. I still love short csl but mostly climb standing.

the choice in 2 is premised by 1, 3 by 2, 4 by 3. You cant start with sta, its pretty far down the stack.

4 is deciding, after youve confirmed fit, that weight distribution on wheels makes you happy..

i simply wouldnt buy a bike with 75 degree sta, seat placement would be impossible. Ditto for 71 degrees. But everything in between is fine because my saddle has long rails.


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## dysfunction (Aug 15, 2009)

It's not only about ass to hands or pedals.


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## drdre (Dec 15, 2005)

drdre said:


> I'm not a frame builder but I can tell you that my l45 disk is disintegrating and my bike with 77 sta helps it and my bike with 74 probably actually hurts it.


I second almost exactly this sentence with the swap of "probably" to "absolutely". I might not be riding now if that trend had'nt occurred. 

The flip side of the coin is that if you have wrist issues, the reverse is likely. Definitely a bit more weight on the arms.


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## XC Only (Jul 9, 2007)

eri said:


> Ok.
> 
> 1 place hands where you want relative to head tube.
> 2 Now select frame with reach that makes you happy standing (rad, relative to bb center and bar width)
> ...


I won't argue with how _you_ decide on how to make _your_ bike fit and/or _your_ decisions on how to evaluate which bikes to buy.

Bike geometry is inter-related, which is the point I made--not to mention external factors such as the type of riding that is en-vogue and the creation of new trails. The geometry that drives sales (often times driven by fashion), simply doesn't work with everyone, everywhere.


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