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Bike Set-up(3 posts)

Bike Set-upWild Bill
May 13, 2001 5:36 AM
I ride with a local club, do all the training rides, a little TT., and touring.
How important is it to have your knee over the pedal axle?
Can it be in front or behind. I have been told that; if the lower part of your leg is shorter than the upper part then you need to put your knee either in front or behind, the opposit is true!
If this is so, how do you measure your leg and how far in front or behind the axle should you be? Please no medical info just plain English that anyone can understand.
Also if your cleat is not 100% right on this will effect your knee over the pedal axle too!!!!
Has anyone got some good advice on this matter? Thanks
web sites....dave
May 13, 2001 6:57 AM
There are lots of opinions about KOP. Check out, and for fit info.

IMO, placing the foot directly over the pedal spindle is nothing but a starting point. What is important is to find the position that gives you the best balance of torque and rpm (cadence). Placing the saddle (and knee) further back allows more torque to be applied, but cadence is reduced (and vice versa). Since power = torque X rpm, both torque and rpm are equally important. It takes a lot of experimentation to find the optimum position. The optimum postion can be different depending on the terrain. If you're riding a hilly route, placing the saddle a little further back may be wise. A more forward position could enhance speed on a flatter route.

Measuring KOP isn't easy to do with great accuracy. Pick a method that's easy to duplicate, and get it set with reasonable accuracy to start. Mark this position on the saddle rails, and then experiment with positions forward and back from the start point. You may find that your seatpost does not permit the needed range of travel, which suggests a different style of post (or a different seat tube angle on your next frame).
web sites....Jon Billheimer
May 13, 2001 10:57 AM
I agree with everything Dave says. For more info. and an opportunity to customize your fit according to your own body proportions, go to This is a software program developed by an engineering firm which allows you to dial in your own custom fit according to your body measurements and the geometry of your bike. It's good stuff!