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  #1  
Old 05-05-2020, 12:34 PM
bigreen505 bigreen505 is offline
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Is saddle fore/aft position important

Not sure if this question is better here or in general, but I'll try it here.

Quick background. I had a fit done several years ago. Respected outfit with all the cool toys. The single biggest problem with the fit is it was done with a saddle that I had recently bought (Specialized Romin). I rode in pain for years and finally came to the conclusion that Specialized saddles just don't work for me. This week I put the bike on the trainer and swapped through saddles from the drawer until I found a few that feel good to go take on real rides. One of the saddles that felt good was an old Turbomatic.

I have long legs and a short torso resulting in a slightly odd bike setup -- the friends across the hall would not approve. The fitters set up the bike with the saddle slammed all the way back on a 30 mm setback post.

Here's the question. Specialized saddles have very long rails, Turbomatics have very short rails. The result is a position just over 1 cm further forward when measuring from the saddle nose top the handlebars. Does this make a difference in pedaling efficiency?

EDIT: As a bit of an afterthought, when I went in for the bike fit, I had 175 mm cranks on. They recommended trying 170 which is what I have now. So in theory, my saddle probably should be 5mm aft of their set position.

Last edited by bigreen505; 05-05-2020 at 12:53 PM.
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  #2  
Old 05-05-2020, 01:10 PM
flying flying is offline
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Quote:
Originally Posted by bigreen505 View Post
Here's the question. Specialized saddles have very long rails, Turbomatics have very short rails. The result is a position just over 1 cm further forward when measuring from the saddle nose top the handlebars. Does this make a difference in pedaling efficiency?
Really only you can answer this question about pedaling efficiency. Fitters & others can only give you theoretical

Aside from saddle rail length....IMO yes "if" that is the only difference you can expect a change in measured distance from bar but....Is that the only difference? Is the "sweet spot" of where you sit on both saddles
the same? As that would also have an effect on measurement.

All that aside I am a firm believer in fit yourself. Only you can know & yes it takes some time but being thoughtful on a ride you can suss it out. After all about setback you can experiment a bit even on saddle while riding

Lastly about setback measurement...While I do note nose of saddle to back of bar as a notation in my fit I am using that number more as a mark of stem length/fit

For setback
I touch rear wheel to wall & measure distance from wall to center of bb
I then measure wall to nose of saddle

I subtract nose distance from BB distance & that is my setback (nose behind BB)

But again...This is just my opinion & how I do things. Everyone is different but I believe you are your best fitter

Last edited by flying; 05-05-2020 at 01:14 PM.
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  #3  
Old 05-05-2020, 03:50 PM
smokersteve smokersteve is offline
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"Is saddle fore/aft position important"

This is where you start when fitting a bike and is very important.
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Old 05-05-2020, 04:08 PM
robt57 robt57 is offline
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Quote:
Originally Posted by smokersteve View Post
"Is saddle fore/aft position important"

This is where you start when fitting a bike and is very important.
Starting point, absolutely!

I'm retired, my gig is being fit, riding & collecting, building bikes. I ride like 10 different bikes. They ALL have the stems bars reach set from the same saddle setback.
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Old 05-05-2020, 07:29 PM
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kiwisimon kiwisimon is offline
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yep, move the saddle till you feel it fits you. are you a spinner or a masher?
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  #6  
Old 05-06-2020, 12:00 PM
John H. John H. is offline
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Saddle height

The specific saddle will largely determine the ideal setback.
Do you know where your KOPS (Knee Over Pedal Spindle)was on the Specialized saddle?
Not trying to say KOPS is gospel- But more that you want to replicate same KOPS with the Turbomatic as a starting point.
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Old 05-06-2020, 12:09 PM
robt57 robt57 is offline
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Quote:
Originally Posted by John H. View Post
The specific saddle will largely determine the ideal setback.
Do you know where your KOPS (Knee Over Pedal Spindle)was on the Specialized saddle?
Not trying to say KOPS is gospel- But more that you want to replicate same KOPS with the Turbomatic as a starting point.
Yes, length to saddle tip sure varies. I adjust for a cradle spot per saddle. I also suggest folk at least try a tip high saddle position to see it if works for them. Does for me, but more so with hammock swayback saddles types.

I never understand the tip low positions I see frequently, and not with super low saddle to bars which I could understand a little...
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Old 05-06-2020, 01:24 PM
macaroon macaroon is offline
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Sounds like a poor bike fitter. Long legs and short torso should more likely mean a more forward saddle position. I'd push your saddle all the way forward, or try an inline seatpost.
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Old 05-06-2020, 07:50 PM
OtayBW OtayBW is offline
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This has made the rounds plenty of times around here, and I think it's really recommended reading for setback and how to evaluate it. http://kirkframeworks.com/2009/06/19/riding-tip-3/
GL
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Old 05-06-2020, 11:02 PM
bigreen505 bigreen505 is offline
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Quote:
Originally Posted by kiwisimon View Post
yep, move the saddle till you feel it fits you. are you a spinner or a masher?
Definitely a spinner.

Quote:
Originally Posted by John H. View Post
The specific saddle will largely determine the ideal setback.
Do you know where your KOPS (Knee Over Pedal Spindle)was on the Specialized saddle?
Not trying to say KOPS is gospel- But more that you want to replicate same KOPS with the Turbomatic as a starting point.
That's a great idea, thanks. I was under the assumption that I can't replicate the position with the Turbomatic, but that may not be true. To be honest, I'm 80% sure it's true, but I will absolutely use your method to see. Might be closer than I think.

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Originally Posted by macaroon View Post
Sounds like a poor bike fitter. Long legs and short torso should more likely mean a more forward saddle position. I'd push your saddle all the way forward, or try an inline seatpost.
Can you explain more why you think that way? Regarding the fitter, I don't have any way to judge that, but I don't think I would ever go back to them. It is a highly respected outfit -- admittedly one that I have complained about on here following the fit session. I have long legs and a stiff lower back, so instead of telling me to change to a saddle that rotates my hips forward, they set me up in a very upright position.

Quote:
Originally Posted by OtayBW View Post
This has made the rounds plenty of times around here, and I think it's really recommended reading for setback and how to evaluate it. http://kirkframeworks.com/2009/06/19/riding-tip-3/
GL
I've read it before, and I don't really know what to make of it. To me either Dave is right that you set saddle height to get the proper leg extension, fore/aft position to get the proper balance -- and hopefully in the process, the correct balance of muscle groups working -- or you the Retul/motion capture crew is correct that you set saddle position, and with it the body position, to optimize the pedaling motion.

This fit was my first foray into the motion capture set. At the risk of rehashing old threads, this group looks to put the rider into specific position and optimize the pedaling motion.
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  #11  
Old 05-07-2020, 01:51 AM
macaroon macaroon is offline
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Quote:
Originally Posted by bigreen505 View Post

Can you explain more why you think that way? Regarding the fitter, I don't have any way to judge that, but I don't think I would ever go back to them. It is a highly respected outfit -- admittedly one that I have complained about on here following the fit session. I have long legs and a stiff lower back, so instead of telling me to change to a saddle that rotates my hips forward, they set me up in a very upright position.
It's a generalisation, and it depends how you sit on the bike. But think about where your centre of mass is (if that's the right term?)

How do you find pedalling up hills when seated?

Have you considered stretching exercises?
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  #12  
Old 05-07-2020, 01:52 AM
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kiwisimon kiwisimon is offline
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TBH get another fit done by another person.
Sounds like the original fit might have gotten things lost in translation and between switching cranks and saddles you position has gotten out of whack.
None of us here can see you on the bike.

If staying home is a problem contact a fitter and may be with video and skype you can get things started and finish it after corona dies down.

If you are a spinner the shorter cranks make sense but the tip of your saddle shouldn't be a marker in bike fit unless you are using the same saddle on different bikes with the same geometries. It can be a guide though,

good luck.
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  #13  
Old 05-07-2020, 08:20 AM
OtayBW OtayBW is offline
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Quote:
Originally Posted by bigreen505 View Post
I've read it before, and I don't really know what to make of it. To me either Dave is right that you set saddle height to get the proper leg extension, fore/aft position to get the proper balance -- and hopefully in the process, the correct balance of muscle groups working -- or you the Retul/motion capture crew is correct that you set saddle position, and with it the body position, to optimize the pedaling motion.
For me, it's all about proper weight distribution which should be considered at both the start and the end of the fitting process....
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  #14  
Old 05-07-2020, 08:46 AM
Smitty2k1 Smitty2k1 is offline
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Quote:
Originally Posted by bigreen505 View Post
I have long legs and a stiff lower back, so instead of telling me to change to a saddle that rotates my hips forward, they set me up in a very upright position.
Hey me too!

If you ever figure out a solution for this, please let me know. I've been in bike fit hell for the 3 years I've been 'seriously' cycling.
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  #15  
Old 05-08-2020, 09:33 AM
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wallymann wallymann is offline
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OMG...that is HUGELY important!

the VERY FOUNDATION of your position is saddle height and fore/aft position relative to the BB center. full stop.

once you've established that foundation, next step is to establish the reach and drop to your bars.
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