Trevor Jeffrey wrote:
Robert wrote in message ...

Trevor Jeffrey wrote:

The knee position remains the same it is the foot and lower leg which are
affected by cleat position.

Yes that's technically true, but it does change the
torso-to-upper-leg-angle slightly, as if one had moved one's seat
*forward* a little bit (not back, as Sorni was implying with the KOPS
reference). Even if the knee position relative to centre bracket is
unchanged, the new angle will cause different loadings on the leg
muscles and knees and this will be felt to a greater or lesser degree,
depending on how well your knees behave in general.

I moved my cleats *back* on my shoes and got a much more restful riding
position, but started getting slight knee pain as well. I have now
shifted my seat forward approx. 8 mm to get back to the original
torso-leg angle and problems have disappeared. Of course to get same arm
stretch forwards, I now have to choose between increasing my handlebar
stem length from 120 to 130 mm or cheating a bit by sawing 1 cm off my
steerer tube to drop the bars a bit.



The knee pain is most probably due to over extension, a slight lowering of
the saddle would have left the knee more bent in its lower position so
reducing femur rotation. It is the femur rotation which seems to upset the
proper functioning of the knee during cycling. Generally a bad move to
lower handlebars except in short distance racing. Try the lowered seat
position.

Trevor

Trevor, your idea works in my case. Moving the seat forward as I did
also had the effect of lowering the seat relative to the centre bracket
by about 3 mm. More or less; I didn't do the trig on it yet.

I rode this way for about 50 km today, pedalling mostly at 105-110
cadence with no trouble at all. Felt too good to be true so I raised the
seat that 3 mm and got that twinge across the back of the knee again,
after only 5 km. So, back down with the seat again . . .

BTW what's _your_ view of what constitutes correct seat height? Where
one can just rest the heel on the pedal without rotating hips? Or even
lower than that?

(this might spark of a ton of postings but it'll be interesting to see
what comes in)

/Robert