Fit Oddity

[grey]

I was trying out bikes today (such fun) and I'm sort of an odd fit - I'm right in between a 54 and 52 in size. I do have trouble with my right knee on some bikes - what I found is while a 52 is PERFECT for the upper body, the knee goes nuts. A 54 offers less maneuverability but wow the difference in the stroke and absolutely no knee problems. It makes NO SENSE. We even tried switching out the crank from one to the other because there was a 1.5mm difference and they thought that might be it.

Does anyone have an explanation?

[SadieKate]

Is this the same model in the same brand? Have you tried other brands and models? 52 and 54 are just numbers. Maybe the geometry isn't quite right for you.

[OakLeaf]

Different sized frames in the same model may have a different seat tube angle, so you may have to change the front-to-back position of the saddle to get the same KOPS. If all the LBS did was match the seat height over the BB, they should also check the front-to-back position.

[VeloVT]

Yeah, sounds like a setback issue to me. Where is your knee hurting? I get a very specific, instantly recognizable pain if I am too far forward -- a tendon that is centered and right above my kneecap. It can get quite painful, but if I stop and push the saddle back, it goes away immediately, during the same ride...

Watch out for anyone who tries to fit you on a bike that's too big for you by moving the seat forward to shorten your reach to the handlebars. They should always determine the right fore-aft saddle position and then fit your reach taking the saddle setback as a given.

[grey]

Yeah, sounds like a setback issue to me. Where is your knee hurting? I get a very specific, instantly recognizable pain if I am too far forward -- a tendon that is centered and right above my kneecap. It can get quite painful, but if I stop and push the saddle back, it goes away immediately, during the same ride...

That's really interesting to know - I will mention it to them when I go back on Friday.

My knee pain is to the right (the outside) of the kneecap. I have degenerative cartilage issues - sometimes a piece actually moves around and will get stuck in a bad spot and take me right down - but I can massage it back out of the way and be just fine.