Are you more or less likely to spin out your back wheel on a steep standing climb with the Uber long stays?
If you change nothing else you'll have less weight on the rear so you're more likely to spin out. However, longer chainstays can allow for higher bars, shorter stems and you don't have to focus as much on keeping the front down. So my real world experience going to 465 mm chainstays is that I haven't noticed an increase in spinning my rear tire on steep climbs. If anything it's probably better since I'm in a more natural position on the bike.
It's interesting to hear the differences in peoples' experiences. I would love to take a spin on a long CS, moderate reach, high stack setup to feel the differences in handling.
I tackle almost every climb standing up. I'd rather mash a higher gear than spin a lower one seated. Honestly, I just stand almost all of the time when I'm riding my bike; it just feels better to me. Plus, I'm a low-proficiency, high-power guy. I started mountain biking three years ago in my forties, but I'm quite strong, so I just hammer through terrain with power rather than finessing things with grace and skill. Haha.
I thought the Spot interview was interesting. What he said made sense--it's a choice. It doesn't cost more to manufacture. It does change how the bike rides, which is something to consider. Some builders, Spot and Pivot for example, still believe in designs that incorporate a short CS.
I've been a longtime proponent of longer CS length, but it is interesting that the current gen Sentinel size L & XL came with longer CS, didn't get great reviews & this year all sizes have the shorter CS length.
I've been a longtime proponent of longer CS length, but it is interesting that the current gen Sentinel size L & XL came with longer CS...
I've been a longtime proponent of longer CS length, but it is interesting that the current gen Sentinel size L & XL came with longer CS, didn't get great reviews & this year all sizes have the shorter CS length.
IMO this just shows that today's bike reviews are quite pointless, reviewers are splitting hair over things that are more impacted by their riding style and terrain and that can be completely irrelevant for the buyers.
Some interesting thoughts from the guys at Spot about chainstay length in a podcast about their new bike on the Bikes & Big Ideas podcast with...
Some interesting thoughts from the guys at Spot about chainstay length in a podcast about their new bike on the Bikes & Big Ideas podcast with Simon Stewart.
Geometry talk starts around 29 minutes in but the whole podcast is a great listen!
Side note: I really dig both Simon's episodes and David Golay's episodes of the Bikes & Big Ideas podcast. I know the pacing of the speech in the David-hosted episodes is challenging for some folks but if you can hang with those episodes there's a ton of cool info and cool people to learn from/about!
I listened to the episode and found it interesting. I have to wonder if some of it is that taller riders are just historically used to bikes with shorter RCs so that’s what test riders end up preferring. Santa Cruz also talked about changes they make when making a bike for taller or shorter riders on their Tallboy episode of The Roller Door and while they didn’t go into detail as much as the Spot discussion, the takeaway was kinda the same that shorter riders preferred longer RCs and taller riders preferred shorter RCs
Just a check in to (Probably.) piss some people off. I'm updating my old home made 26" DH bike to take 27.5" wheels. It's got 9.5" travel and the chain stays are growing from 16.5" to a whopping 17.25"! I know. They're getting kind of long, but I had to add 3/4" to fit those huge wheels.
Just a check in to (Probably.) piss some people off. I'm updating my old home made 26" DH bike to take 27.5" wheels. It's got 9.5"...
Just a check in to (Probably.) piss some people off. I'm updating my old home made 26" DH bike to take 27.5" wheels. It's got 9.5" travel and the chain stays are growing from 16.5" to a whopping 17.25"! I know. They're getting kind of long, but I had to add 3/4" to fit those huge wheels.
I mean, you're a traitor, but at least you didn't talk about fc/rc ratio
I listened to the episode and found it interesting. I have to wonder if some of it is that taller riders are just historically used to...
I listened to the episode and found it interesting. I have to wonder if some of it is that taller riders are just historically used to bikes with shorter RCs so that’s what test riders end up preferring. Santa Cruz also talked about changes they make when making a bike for taller or shorter riders on their Tallboy episode of The Roller Door and while they didn’t go into detail as much as the Spot discussion, the takeaway was kinda the same that shorter riders preferred longer RCs and taller riders preferred shorter RCs
Taller riders historically getting the shaft with the one size fits all chainstay approach, has been my experience.
It takes time to adapt to a longer rear end and riding through your feet and hips. The longer you've been on a short rear end, the longer it takes to recalibrate ones riding style, but the benefits are certainly there afterwards. There's just a weird in between period that makes you think short rear ends aren't so bad.
I listened to the episode and found it interesting. I have to wonder if some of it is that taller riders are just historically used to...
I listened to the episode and found it interesting. I have to wonder if some of it is that taller riders are just historically used to bikes with shorter RCs so that’s what test riders end up preferring. Santa Cruz also talked about changes they make when making a bike for taller or shorter riders on their Tallboy episode of The Roller Door and while they didn’t go into detail as much as the Spot discussion, the takeaway was kinda the same that shorter riders preferred longer RCs and taller riders preferred shorter RCs
Taller riders historically getting the shaft with the one size fits all chainstay approach, has been my experience.It takes time to adapt to a longer rear...
Taller riders historically getting the shaft with the one size fits all chainstay approach, has been my experience.
It takes time to adapt to a longer rear end and riding through your feet and hips. The longer you've been on a short rear end, the longer it takes to recalibrate ones riding style, but the benefits are certainly there afterwards. There's just a weird in between period that makes you think short rear ends aren't so bad.
Yeah, that’s why Im wondering if theres selection bias as test riders as a population are likely to have been riding for a long time.
What do people like for sizing on a fun park/DH bike like the new Norco Torrent or Transition TR11 compared to trail/enduro bikes?
I haven't owned a bike with a dual crown in quite a few years. My sweet spot for a 160/170 bike is 500 reach and 64 head angle. Downsize the DH bike a little on reach or keep it the same as the pedal bike? Whistler laps, shuttling certain steep loamy spots, plenty of tech but still fun on Aline, no racing.
What do people like for sizing on a fun park/DH bike like the new Norco Torrent or Transition TR11 compared to trail/enduro bikes?I haven't owned a...
What do people like for sizing on a fun park/DH bike like the new Norco Torrent or Transition TR11 compared to trail/enduro bikes?
I haven't owned a bike with a dual crown in quite a few years. My sweet spot for a 160/170 bike is 500 reach and 64 head angle. Downsize the DH bike a little on reach or keep it the same as the pedal bike? Whistler laps, shuttling certain steep loamy spots, plenty of tech but still fun on Aline, no racing.
Little shorter on reach, little higher on stack, little shorter cs
What do people like for sizing on a fun park/DH bike like the new Norco Torrent or Transition TR11 compared to trail/enduro bikes?I haven't owned a...
What do people like for sizing on a fun park/DH bike like the new Norco Torrent or Transition TR11 compared to trail/enduro bikes?
I haven't owned a bike with a dual crown in quite a few years. My sweet spot for a 160/170 bike is 500 reach and 64 head angle. Downsize the DH bike a little on reach or keep it the same as the pedal bike? Whistler laps, shuttling certain steep loamy spots, plenty of tech but still fun on Aline, no racing.
I like the bar height and total reach to be pretty similar so the fit/riding position feels the same between bikes. Then, ideally, pair that with longer stays and slacker HTA on the dh bike to get slacker and longer while preserving front-rear balance.
That being said, as long as the fit is relatively close you don’t need to overthink it. You’re gonna be having way too much fun on Aline to wonder if your reach is 10mm too short.
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like the feeling of standing on the rear pegs of a BMX bike and feeling the whole front end sort of flick around the pivot point of the rear wheel. Of course, on a mountain bike, we don’t have pegs, but if we have short chainstays the flickable feeling comes from the phenomenon of turning the bars and feeling the whole front end flick around, pivoting around the back end of the bike.
I think that this added responsiveness at the bars is something that a lot of riders like. Especially if those riders are hunched over and putting weight on the front of their bike (a body position adapted to make up for lack of front end grip/bikes with too low of stack…) It would follow that you would want more responsiveness since you are sort of hindering that front end from coming around with your weight. If you were to put that rider on a bike with a more balanced ratio, they might feel like the front end isn’t as responsive because now there is too much weight on the bars, and the payment point has moved forward and so the bars aren’t having as big of an impact on the turning.
I think this is the reason that we have such massive arguments about chainstay length and handling. The people who are looking for a more responsive feeling at the handlebars are not going to like a long chain stay bikes. And people who want a bike that steers better through the feet are going to hate short chain stay bikes.
Flickable means its responsive to inputs and changes direction (rotates) quickly without too much effort. It doesn't mean unstable though as it still gives you the confidence to lean on it aggressively.
Front end turning while standing on rear pegs is probably the opposite of what Flickable is...
That's how I see it. The term is used for bikes and cars. And it usually means you throw it in a corner, aggressively, it will hook up, rotate and won't spit you off.
Based on that it doesn't have an relation with one geometry value, it has more to do with balance and grip levels to handle the energy of inputs.
Flickable means its responsive to inputs and changes direction (rotates) quickly without too much effort. It doesn't mean unstable though as it still gives you the...
Flickable means its responsive to inputs and changes direction (rotates) quickly without too much effort. It doesn't mean unstable though as it still gives you the confidence to lean on it aggressively.
Front end turning while standing on rear pegs is probably the opposite of what Flickable is...
That's how I see it. The term is used for bikes and cars. And it usually means you throw it in a corner, aggressively, it will hook up, rotate and won't spit you off.
Based on that it doesn't have an relation with one geometry value, it has more to do with balance and grip levels to handle the energy of inputs.
I’m just trying to decode the people saying that making chainstays longer makes a bike less flickable.
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like...
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like the feeling of standing on the rear pegs of a BMX bike and feeling the whole front end sort of flick around the pivot point of the rear wheel. Of course, on a mountain bike, we don’t have pegs, but if we have short chainstays the flickable feeling comes from the phenomenon of turning the bars and feeling the whole front end flick around, pivoting around the back end of the bike.
I think that this added responsiveness at the bars is something that a lot of riders like. Especially if those riders are hunched over and putting weight on the front of their bike (a body position adapted to make up for lack of front end grip/bikes with too low of stack…) It would follow that you would want more responsiveness since you are sort of hindering that front end from coming around with your weight. If you were to put that rider on a bike with a more balanced ratio, they might feel like the front end isn’t as responsive because now there is too much weight on the bars, and the payment point has moved forward and so the bars aren’t having as big of an impact on the turning.
I think this is the reason that we have such massive arguments about chainstay length and handling. The people who are looking for a more responsive feeling at the handlebars are not going to like a long chain stay bikes. And people who want a bike that steers better through the feet are going to hate short chain stay bikes.
That is literally the exact opposite of flickable.
Also long chainstays doesn’t give you more leverage over your rear wheel, the opposite is true.
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like...
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like the feeling of standing on the rear pegs of a BMX bike and feeling the whole front end sort of flick around the pivot point of the rear wheel. Of course, on a mountain bike, we don’t have pegs, but if we have short chainstays the flickable feeling comes from the phenomenon of turning the bars and feeling the whole front end flick around, pivoting around the back end of the bike.
I think that this added responsiveness at the bars is something that a lot of riders like. Especially if those riders are hunched over and putting weight on the front of their bike (a body position adapted to make up for lack of front end grip/bikes with too low of stack…) It would follow that you would want more responsiveness since you are sort of hindering that front end from coming around with your weight. If you were to put that rider on a bike with a more balanced ratio, they might feel like the front end isn’t as responsive because now there is too much weight on the bars, and the payment point has moved forward and so the bars aren’t having as big of an impact on the turning.
I think this is the reason that we have such massive arguments about chainstay length and handling. The people who are looking for a more responsive feeling at the handlebars are not going to like a long chain stay bikes. And people who want a bike that steers better through the feet are going to hate short chain stay bikes.
Yea and so what are they propelling with a light movement? The whole bike? No that’s not how it works. They probably aren’t flicking the back end since short CSs put more weight on the rear. Having more weight on the rear means the front will feel lighter and more responsive.
You’ve obviously ridden short Cs bikes and agree they are easier to break loose and move the rear around. A simple explanation is because a slight weight shift forward unweights the rear far more than any weight distribution from fc:rc and a short rear end is obviously easier to move than a long one because it is closer to your feet. But I assume you’re being difficult because you have a theory of your own. Care to explain?
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like...
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like the feeling of standing on the rear pegs of a BMX bike and feeling the whole front end sort of flick around the pivot point of the rear wheel. Of course, on a mountain bike, we don’t have pegs, but if we have short chainstays the flickable feeling comes from the phenomenon of turning the bars and feeling the whole front end flick around, pivoting around the back end of the bike.
I think that this added responsiveness at the bars is something that a lot of riders like. Especially if those riders are hunched over and putting weight on the front of their bike (a body position adapted to make up for lack of front end grip/bikes with too low of stack…) It would follow that you would want more responsiveness since you are sort of hindering that front end from coming around with your weight. If you were to put that rider on a bike with a more balanced ratio, they might feel like the front end isn’t as responsive because now there is too much weight on the bars, and the payment point has moved forward and so the bars aren’t having as big of an impact on the turning.
I think this is the reason that we have such massive arguments about chainstay length and handling. The people who are looking for a more responsive feeling at the handlebars are not going to like a long chain stay bikes. And people who want a bike that steers better through the feet are going to hate short chain stay bikes.
Because of this thread (thanks) my factors to consider a bikes descending feel come from F/R ratio and RAD angle. For me the different styles of bikes require different ratios, a higher RAD angle likely requires more rear center. I'm currently riding the following as a shorter guy (5'6") and feel its a great spot for me. (I get we can adapt)
Trail Bike - 1.8 F/R (64.27% F) with 59 degree RAD angle
Enduro - 1.78 F/R (63.98% Fr) with 60 degree RAD angle. Previously was on 1.86 + 59.4 and struggled for front end grip. This is a very similar ratio seen on XL bikes.
What I find interesting is XL numbers. Generally I would say most people riding that bike get a 1.92F/R with 59 Rad angle, which I'd feel like I'd struggle to ride. Trying to get to my ratios would need 483 chainstays and to add 100mm of stack to the 660 stack of that bike (70mm rise stem + 30mm spacers to get a 60 degree RAD angle). That bike probably doesn't exist?
I also think there something to be said for the amount of change in the last 10 years. Using the bronson as a standard, comparing 2016 to 2025, smalls have increased 1.64 to 1.76 (+.07) and 60 to 62.9 (+2.9) and RAD grew 2.5%, an XL from 1.83 to 1.91 (0.04) and 56.98 to 60.2 (+3.2) and grew 2.7% RAD. Larges went from 1.75 to 1.86 (0.06) and 58.7 to 59.8 (1.1) and RAD remained the same. I maybe infer that smalls have seen the largest change to reduce front end pressure, while XL have done the most to move their bars up, which also sacrifice front end grip. I dunno you tell me.
Some tools that are sweet at calculating those numbers.
Am I (or this thread) right on F/R ratios and rad angles across sizes for the same bike? What do you all think is your preferred F/R and rad angle? Should we all have the same, different or what?
Because of this thread (thanks) my factors to consider a bikes descending feel come from F/R ratio and RAD angle. For me the different styles of bikes require different ratios, a higher RAD angle likely requires more rear center. I'm currently riding the following as a shorter guy (5'6") and feel its a great spot for me. (I get we can adapt)
Trail Bike - 1.8 F/R (64.27% F) with 59 degree RAD angle
Enduro - 1.78 F/R (63.98% Fr) with 60 degree RAD angle. Previously was on 1.86 + 59.4 and struggled for front end grip. This is a very similar ratio seen on XL bikes.
What I find interesting is XL numbers. Generally I would say most people riding that bike get a 1.92F/R with 59 Rad angle, which I'd feel like I'd struggle to ride. Trying to get to my ratios would need 483 chainstays and to add 100mm of stack to the 660 stack of that bike (70mm rise stem + 30mm spacers to get a 60 degree RAD angle). That bike probably doesn't exist?
I also think there something to be said for the amount of change in the last 10 years. Using the bronson as a standard, comparing 2016 to 2025, smalls have increased 1.64 to 1.76 (+.07) and 60 to 62.9 (+2.9) and RAD grew 2.5%, an XL from 1.83 to 1.91 (0.04) and 56.98 to 60.2 (+3.2) and grew 2.7% RAD. Larges went from 1.75 to 1.86 (0.06) and 58.7 to 59.8 (1.1) and RAD remained the same. I maybe infer that smalls have seen the largest change to reduce front end pressure, while XL have done the most to move their bars up, which also sacrifice front end grip. I dunno you tell me.
Some tools that are sweet at calculating those numbers.
Am I (or this thread) right on F/R ratios and rad angles across sizes for the same bike? What do you all think is your preferred F/R and rad angle? Should we all have the same, different or what?
I hear you, but last time I brought up RAD, it wasn't received well. I wasn't involved with the forums when Lee's stuff was coming out so I don't know the history of how well his work has been received or what not. I still think people will start paying more attention to rad or rider triangle or whatever is en vogue, just don't call it RAD lol.
From my bikes, I noticed that i've naturally settled between 56-58 degrees - favoring ~57 with my most recent enduro bike.
With F/R ratio, I find short chainstay bikes better to ride when the wheelbase is longer, but i think this is confounded with stack. As long as im riding a RAD angle and distance that's comfortable to me, I find it easy to adjust my riding for different F/R ratio bikes.
I hear you, but last time I brought up RAD, it wasn't received well. I wasn't involved with the forums when Lee's stuff was coming out...
I hear you, but last time I brought up RAD, it wasn't received well. I wasn't involved with the forums when Lee's stuff was coming out so I don't know the history of how well his work has been received or what not. I still think people will start paying more attention to rad or rider triangle or whatever is en vogue, just don't call it RAD lol.
From my bikes, I noticed that i've naturally settled between 56-58 degrees - favoring ~57 with my most recent enduro bike.
With F/R ratio, I find short chainstay bikes better to ride when the wheelbase is longer, but i think this is confounded with stack. As long as im riding a RAD angle and distance that's comfortable to me, I find it easy to adjust my riding for different F/R ratio bikes.
Rad is somewhat irrelevant when used by itself, which is kind of what Lee was trying to do.
Rad angle is a bit more useful when combined with f/r ratio.
On xl bikes having higher ratios typically, I do believe there's something there in the relationship between axle height and rider's cg. When the 32" bikes arrive, I expect ratios closer to 1.8 for xl and xxl bikes to be a bit more normalized. At 6', a 1.8 ratio has been best for me, particularly when riding blind trails/stages.
If you change nothing else you'll have less weight on the rear so you're more likely to spin out. However, longer chainstays can allow for higher bars, shorter stems and you don't have to focus as much on keeping the front down. So my real world experience going to 465 mm chainstays is that I haven't noticed an increase in spinning my rear tire on steep climbs. If anything it's probably better since I'm in a more natural position on the bike.
It's interesting to hear the differences in peoples' experiences. I would love to take a spin on a long CS, moderate reach, high stack setup to feel the differences in handling.
I tackle almost every climb standing up. I'd rather mash a higher gear than spin a lower one seated. Honestly, I just stand almost all of the time when I'm riding my bike; it just feels better to me. Plus, I'm a low-proficiency, high-power guy. I started mountain biking three years ago in my forties, but I'm quite strong, so I just hammer through terrain with power rather than finessing things with grace and skill. Haha.
I thought the Spot interview was interesting. What he said made sense--it's a choice. It doesn't cost more to manufacture. It does change how the bike rides, which is something to consider. Some builders, Spot and Pivot for example, still believe in designs that incorporate a short CS.
I've been a longtime proponent of longer CS length, but it is interesting that the current gen Sentinel size L & XL came with longer CS, didn't get great reviews & this year all sizes have the shorter CS length.
IMO this just shows that today's bike reviews are quite pointless, reviewers are splitting hair over things that are more impacted by their riding style and terrain and that can be completely irrelevant for the buyers.
I listened to the episode and found it interesting. I have to wonder if some of it is that taller riders are just historically used to bikes with shorter RCs so that’s what test riders end up preferring. Santa Cruz also talked about changes they make when making a bike for taller or shorter riders on their Tallboy episode of The Roller Door and while they didn’t go into detail as much as the Spot discussion, the takeaway was kinda the same that shorter riders preferred longer RCs and taller riders preferred shorter RCs
Just a check in to (Probably.) piss some people off. I'm updating my old home made 26" DH bike to take 27.5" wheels. It's got 9.5" travel and the chain stays are growing from 16.5" to a whopping 17.25"! I know. They're getting kind of long, but I had to add 3/4" to fit those huge wheels.
I mean, you're a traitor, but at least you didn't talk about fc/rc ratio
Taller riders historically getting the shaft with the one size fits all chainstay approach, has been my experience.
It takes time to adapt to a longer rear end and riding through your feet and hips. The longer you've been on a short rear end, the longer it takes to recalibrate ones riding style, but the benefits are certainly there afterwards. There's just a weird in between period that makes you think short rear ends aren't so bad.
Yeah, that’s why Im wondering if theres selection bias as test riders as a population are likely to have been riding for a long time.
Just got through the Spot podcast and... Am I the only one that heard more or less an hour of serving koolaid?
What do people like for sizing on a fun park/DH bike like the new Norco Torrent or Transition TR11 compared to trail/enduro bikes?
I haven't owned a bike with a dual crown in quite a few years. My sweet spot for a 160/170 bike is 500 reach and 64 head angle. Downsize the DH bike a little on reach or keep it the same as the pedal bike? Whistler laps, shuttling certain steep loamy spots, plenty of tech but still fun on Aline, no racing.
Little shorter on reach, little higher on stack, little shorter cs
I like the bar height and total reach to be pretty similar so the fit/riding position feels the same between bikes. Then, ideally, pair that with longer stays and slacker HTA on the dh bike to get slacker and longer while preserving front-rear balance.
That being said, as long as the fit is relatively close you don’t need to overthink it. You’re gonna be having way too much fun on Aline to wonder if your reach is 10mm too short.
I came back to check in and let everybody know that I figured out what flickable means. I am pretty sure that it means something like the feeling of standing on the rear pegs of a BMX bike and feeling the whole front end sort of flick around the pivot point of the rear wheel. Of course, on a mountain bike, we don’t have pegs, but if we have short chainstays the flickable feeling comes from the phenomenon of turning the bars and feeling the whole front end flick around, pivoting around the back end of the bike.
I think that this added responsiveness at the bars is something that a lot of riders like. Especially if those riders are hunched over and putting weight on the front of their bike (a body position adapted to make up for lack of front end grip/bikes with too low of stack…) It would follow that you would want more responsiveness since you are sort of hindering that front end from coming around with your weight. If you were to put that rider on a bike with a more balanced ratio, they might feel like the front end isn’t as responsive because now there is too much weight on the bars, and the payment point has moved forward and so the bars aren’t having as big of an impact on the turning.
I think this is the reason that we have such massive arguments about chainstay length and handling. The people who are looking for a more responsive feeling at the handlebars are not going to like a long chain stay bikes. And people who want a bike that steers better through the feet are going to hate short chain stay bikes.
lmao
Flickable means its responsive to inputs and changes direction (rotates) quickly without too much effort. It doesn't mean unstable though as it still gives you the confidence to lean on it aggressively.
Front end turning while standing on rear pegs is probably the opposite of what Flickable is...
That's how I see it. The term is used for bikes and cars. And it usually means you throw it in a corner, aggressively, it will hook up, rotate and won't spit you off.
Based on that it doesn't have an relation with one geometry value, it has more to do with balance and grip levels to handle the energy of inputs.
I’m just trying to decode the people saying that making chainstays longer makes a bike less flickable.
That is literally the exact opposite of flickable.
Also long chainstays doesn’t give you more leverage over your rear wheel, the opposite is true.
Also, long chainstays ftw
I’m just trying to figure out what they’re flicking. Any clues?
I’m with you
https://www.merriam-webster.com/dictionary/flick
Yea and so what are they propelling with a light movement? The whole bike? No that’s not how it works. They probably aren’t flicking the back end since short CSs put more weight on the rear. Having more weight on the rear means the front will feel lighter and more responsive.
The issue goes back to the thought of only one dimension on the geometry charts giving the bike a certain feeling..
You’ve obviously ridden short Cs bikes and agree they are easier to break loose and move the rear around. A simple explanation is because a slight weight shift forward unweights the rear far more than any weight distribution from fc:rc and a short rear end is obviously easier to move than a long one because it is closer to your feet. But I assume you’re being difficult because you have a theory of your own. Care to explain?
No no no, don't go there. We've been over this. Just let it go. We've had pages of trying to explain things back and forth with no success.
Came back for your hat I see
With the recent talk on the "catch all" forum on geo, as well as pinkbikes recent article, figured I'd bring back up this thread for people who nerd out on this.
https://www.vitalmtb.com/forums/hub/2026-mtb-tech-rumors-and-innovation-longer-and-slacker?page=232 - Now talking geo
https://www.pinkbike.com/news/analysis-chainstay-length-debate-solved-according-to-pinkbike-readers.html - not one CS is best
Because of this thread (thanks) my factors to consider a bikes descending feel come from F/R ratio and RAD angle. For me the different styles of bikes require different ratios, a higher RAD angle likely requires more rear center. I'm currently riding the following as a shorter guy (5'6") and feel its a great spot for me. (I get we can adapt)
Trail Bike - 1.8 F/R (64.27% F) with 59 degree RAD angle
Enduro - 1.78 F/R (63.98% Fr) with 60 degree RAD angle. Previously was on 1.86 + 59.4 and struggled for front end grip. This is a very similar ratio seen on XL bikes.
It makes me thinks lee McCormick was onto something with RAD angle, but was probably off on getting RAD length for riders of different sizes. https://www.pinkbike.com/u/leelikesbikes/blog/dialing-in-your-bike-for-your-riding-style.html
What I find interesting is XL numbers. Generally I would say most people riding that bike get a 1.92F/R with 59 Rad angle, which I'd feel like I'd struggle to ride. Trying to get to my ratios would need 483 chainstays and to add 100mm of stack to the 660 stack of that bike (70mm rise stem + 30mm spacers to get a 60 degree RAD angle). That bike probably doesn't exist?
I also think there something to be said for the amount of change in the last 10 years. Using the bronson as a standard, comparing 2016 to 2025, smalls have increased 1.64 to 1.76 (+.07) and 60 to 62.9 (+2.9) and RAD grew 2.5%, an XL from 1.83 to 1.91 (0.04) and 56.98 to 60.2 (+3.2) and grew 2.7% RAD. Larges went from 1.75 to 1.86 (0.06) and 58.7 to 59.8 (1.1) and RAD remained the same. I maybe infer that smalls have seen the largest change to reduce front end pressure, while XL have done the most to move their bars up, which also sacrifice front end grip. I dunno you tell me.
Some tools that are sweet at calculating those numbers.
https://www.bike-stats.de/en/geometrie_vergleich
https://madscientistmtb.com/bike-geometry-calculator/
Am I (or this thread) right on F/R ratios and rad angles across sizes for the same bike? What do you all think is your preferred F/R and rad angle? Should we all have the same, different or what?
I hear you, but last time I brought up RAD, it wasn't received well. I wasn't involved with the forums when Lee's stuff was coming out so I don't know the history of how well his work has been received or what not. I still think people will start paying more attention to rad or rider triangle or whatever is en vogue, just don't call it RAD lol.
From my bikes, I noticed that i've naturally settled between 56-58 degrees - favoring ~57 with my most recent enduro bike.
With F/R ratio, I find short chainstay bikes better to ride when the wheelbase is longer, but i think this is confounded with stack. As long as im riding a RAD angle and distance that's comfortable to me, I find it easy to adjust my riding for different F/R ratio bikes.
Rad is somewhat irrelevant when used by itself, which is kind of what Lee was trying to do.
Rad angle is a bit more useful when combined with f/r ratio.
On xl bikes having higher ratios typically, I do believe there's something there in the relationship between axle height and rider's cg. When the 32" bikes arrive, I expect ratios closer to 1.8 for xl and xxl bikes to be a bit more normalized. At 6', a 1.8 ratio has been best for me, particularly when riding blind trails/stages.
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