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  #16  
Old 09-15-2017, 09:41 AM
weiwentg weiwentg is offline
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Originally Posted by Peter P. View Post
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Literature I've read from Lennard Zinn and Cervelo suggests shorter riders are merely scaled down versions of taller riders, and a 73 degree seat angle works in most cases....
The way you phrased this is likely putting people off. I think you mean that the literature suggests that there's no evidence that the average leg/torso proportions differ by height. So, all else equal, 73 degrees might sit right at the middle of the distribution of leg/torso proportions, so it would fit the most riders across the height spectrum. If the literature is correct, that is. That is something I could believe.

Personally, when I got into riding, I found myself sliding all the way forward on the saddle all the time. I had a small Giant TCR with a 74 STA and a Thomson post, and I put my saddle all the way forward to get comfortable. So, clearly I prefer riding quite far forward. I now have a 76 STA, no setback post, saddle in the middle. This is pretty comfortable for me. So, I'm on the short side of the height distribution, and I'm simultaneously on the short leg side of the distribution. So, you can say that 73 STA will work for most people, and I can believe you, but I can still believe that it doesn't quite do it for me.
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  #17  
Old 09-15-2017, 01:24 PM
Bonesbrigade Bonesbrigade is offline
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Originally Posted by weiwentg View Post
The way you phrased this is likely putting people off. I think you mean that the literature suggests that there's no evidence that the average leg/torso proportions differ by height. So, all else equal, 73 degrees might sit right at the middle of the distribution of leg/torso proportions, so it would fit the most riders across the height spectrum. If the literature is correct, that is. That is something I could believe.

Personally, when I got into riding, I found myself sliding all the way forward on the saddle all the time. I had a small Giant TCR with a 74 STA and a Thomson post, and I put my saddle all the way forward to get comfortable. So, clearly I prefer riding quite far forward. I now have a 76 STA, no setback post, saddle in the middle. This is pretty comfortable for me. So, I'm on the short side of the height distribution, and I'm simultaneously on the short leg side of the distribution. So, you can say that 73 STA will work for most people, and I can believe you, but I can still believe that it doesn't quite do it for me.
Wow, that sounds pretty far forward. I'm curious what your saddle height is? and how far your tip of saddle is behind (or forward!) of the BB?

Also, is this a setup you use for a road bike?
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  #18  
Old 09-15-2017, 02:10 PM
weiwentg weiwentg is offline
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Originally Posted by Bonesbrigade View Post
Wow, that sounds pretty far forward. I'm curious what your saddle height is? and how far your tip of saddle is behind (or forward!) of the BB?

Also, is this a setup you use for a road bike?
Yep, it's a road bike! Saddle height is 640mm (center of BB to top of saddle), and I'm not sure how far the saddle tip is behind the BB! The original fit diagram shows it right in line with the BB. Is that normal? Abnormal? Highly abnormal?
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  #19  
Old 09-15-2017, 02:49 PM
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false_Aest false_Aest is offline
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Originally Posted by Bonesbrigade View Post
and how far your tip of saddle is behind (or forward!) of the BB?
If you want this you probably also want to know the make/model of the saddle too

.... because like saddle lengths + rails probably differ or he could be whuzhisbutt and cut the nose off of his saddle for UCI stupidity.
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  #20  
Old 09-15-2017, 05:08 PM
OtayBW OtayBW is offline
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Originally Posted by weiwentg View Post
Yep, it's a road bike! Saddle height is 640mm (center of BB to top of saddle), and I'm not sure how far the saddle tip is behind the BB! The original fit diagram shows it right in line with the BB. Is that normal? Abnormal? Highly abnormal?
I think maybe it's a little Abby Normal....https://i.imgur.com/cZISZjC.gif
Actually, most folks that I know of tend to have at least a few cm of setback.
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Last edited by OtayBW; 09-15-2017 at 05:11 PM.
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  #21  
Old 09-15-2017, 06:03 PM
Bonesbrigade Bonesbrigade is offline
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Originally Posted by weiwentg View Post
Yep, it's a road bike! Saddle height is 640mm (center of BB to top of saddle), and I'm not sure how far the saddle tip is behind the BB! The original fit diagram shows it right in line with the BB. Is that normal? Abnormal? Highly abnormal?
Setback is proportional to saddle height in general. People that run higher saddles tend to have more setback. Your saddle is quite low, so you likely prefer less setback. I'm not tall - 5'8 and I run approx 6cm of setback with a normal length saddle model (selle Italia slr). That's pretty average for my height.

It sounds like you are on less than normal setback, but if that's what you feel comfortable then all is good. Have you ever experimented with more setback? If you do experiment, make sure you lower your saddle height to match your preferred leg extension. You're also going to want to shorten your stem and bar height proportionately if you want to make a true comparison.

Last edited by Bonesbrigade; 09-15-2017 at 06:19 PM.
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  #22  
Old 09-15-2017, 06:06 PM
Bonesbrigade Bonesbrigade is offline
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Originally Posted by false_Aest View Post
If you want this you probably also want to know the make/model of the saddle too

.... because like saddle lengths + rails probably differ or he could be whuzhisbutt and cut the nose off of his saddle for UCI stupidity.
Yeah I get that - I'm just assuming he's running a "normal" length saddle. My TT saddle is a full 5cm further back compared to my road saddles as it's one of those nose-less varieties.
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  #23  
Old 09-20-2017, 11:36 AM
weiwentg weiwentg is offline
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Quote:
Originally Posted by OtayBW View Post
I think maybe it's a little Abby Normal....https://i.imgur.com/cZISZjC.gif
Actually, most folks that I know of tend to have at least a few cm of setback.
Haven't had time to get out the measuring tape. But yes, on both my Vanilla and my stock Gunnar Crosshairs, the tip of my saddle is about in line with the BB center.

That said, the saddle in question is a Fizik Arione. Those are known for being long saddles.

Quote:
Originally Posted by Bonesbrigade View Post
Setback is proportional to saddle height in general. People that run higher saddles tend to have more setback. Your saddle is quite low, so you likely prefer less setback. I'm not tall - 5'8 and I run approx 6cm of setback with a normal length saddle model (selle Italia slr). That's pretty average for my height.

It sounds like you are on less than normal setback, but if that's what you feel comfortable then all is good. Have you ever experimented with more setback? If you do experiment, make sure you lower your saddle height to match your preferred leg extension. You're also going to want to shorten your stem and bar height proportionately if you want to make a true comparison.
I think I mentioned earlier in the thread that when I started riding, my setback was in the typical range for road riders. I found myself consistently moving myself forward on the saddle.

A bike fit session with a Serotta dealer got me to a 75.5 or 76 degree STA. I stopped moving forward. I haven't got any particular desire to experiment with increased setback right now. I don't foresee wanting to do so.

I'm well aware that it's a rule of thumb that the saddle nose shouldn't be ahead of the BB center. Rules of thumb is that they work for the average rider. But, what works for people on average may not work for every person.

In my case, the rule of thumb that got me was that if you can put a foot down at a light, your saddle's too low. I kept moving my saddle up, and I kept getting knee pain, so I moved it back to about 660mm. That's about the height we originally fit the bike for. Then, this year, I got some knee pain that didn't resolve. I saw a fitter in Minneapolis. They moved it down by 20mm. Knee pain resolved. No detriment to my power that I can tell. But I could put a foot down while stopped with the saddle at 660!
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