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Old 10-13-2016, 11:38 PM
fthefox fthefox is offline
Join Date: Feb 2013
Posts: 61
Reproducing fit with different saddle

I read the thread about measuring contact points. If you ride the same saddle, it seems duable following the steps described in the thread. What happens if you change saddle? As I will likely try another saddle on my P2 over the winter, how can I transfer my position - I have been fitted - without seeing a fitter? My position is confortable, I do not really want to change anything. Which steps shall I follow to make sure I am in the same position with another saddle? I suspect my knee position should be the starting point. A plumb line relative to the BB could do the trick but I find plumb line measurements pretty inaccurate. Any advice?

Thank you.

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Old 10-18-2016, 05:28 PM
drewellison's Avatar
drewellison drewellison is offline
Senior Member
Join Date: Jan 2008
Posts: 871
Different saddles

I thought about this quite a bit but don't have experience doing this since all my bikes have the same saddle. But in case I had different saddles, what I'd do is ...
1. Put bike #1 in a trainer and get in a comfortable riding position on the saddle. Have the better half measure from the back edge of the saddle to the back edge of my back side. Or maybe I could do that part by feel.
2. Put bike #2 in the trainer, get in the same riding position, and do the same measurement.
3. Calculate out the difference.
4. Do a little math and convert the differenct to the tip of the saddle.

Maybe do the same in different riding positions - on hoods, on drops, on tops?

Now you've got a number to use for calculating your fit on your different bikes/saddles.
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Old 10-25-2016, 10:25 AM
fthefox fthefox is offline
Join Date: Feb 2013
Posts: 61
Thanks drewellison,

I am not sure it would work as saddles vary in length on top and at the rails.

1. I think the only ''scientific'' solution is to make sure the knee is at the same place relative to the BB on both saddles. I could get on the bike with the rear wheel against a wall, get somebody to measure the distance from the wall to my knee cap on saddle 1 and replicate the process on saddle 2.

2. If I want to avoid the pumb line going down the knee, I could get a measurement using a carpenter square from the ground. I will buy that right away: Moreover, if I mark my knee cap precisely with the crank arms being horizontal, I can probably figure out the proper saddle height.

3. I guess a fitter might chime in. ;-)


Last edited by fthefox; 10-25-2016 at 10:35 AM.
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Old 10-25-2016, 09:37 PM
11.4 11.4 is offline
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Join Date: Dec 2003
Posts: 3,887
There really is no answer for you. You have to ride the new saddle (or new bike, or new bars, or new pedals, or whatever) and learn what parts of you adjust to the new equipment for the better and which for the worse. Why did you change saddles? To improve your ability to rotate your hips? Or to support greater power with a slightly higher saddle position? Or to solve a lower back problem? You change equipment, you've permanently changed the detail of your fit. You can't expect to come to the same place with different equipment simply by a formula or measurement, because you are changing certain aspects of how you ride. And if you have two bikes with different equipment such that one allows you to adjust to a different hip or lower back configuration, you may not be able to ride the first one again anyway. But it all depends on your own personal needs and morphology.
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Old 10-27-2016, 06:55 AM
Little Bill Little Bill is offline
Join Date: Jan 2013
Posts: 38
If you cant replicate the knee position by yourself, I like to compare the saddles at their width near my sit bones. Pick a spot on the old saddle and then determine the new saddle's same spot (via width) Determine seat height to the spot on the old saddle, then install new saddle, establishing fore/aft on the width, and height to the same spot of the width.

Boy that sounds messy! It works normally within a mm or two...
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