Hi. New to Forum. Trying to decide between a Trek FX 3 and Verve 3. I used to be an avid cyclist riding 40-60 miles daily -30 years ago. Tore up both knees. Looking for a commuter to ride 5 miles daily and 10-15 on weekend on hilly road terrain . Most importiant is to minimize degrees of flexion of my knee; the more bent the more pain. While I know I can raise the seat, it is a matter of other fit components also. I think the Verve has a 170mm crankset while the FX is 175mm. Does anyone have any experience riding either with bad knees (pattello-femoral syndrome/kneecap compression) and/or recommendations. Rode both but hard to tell on a short test ride. Like the lightness and nimbleness of FX but wonder if longer crankshaft will irritate knees more. Greatly appreciate any thoughts...

Hi. Welcome to the Forums. You might want to post this question in the Commuting or Fitting forums.

Thread moved from Forum Suggestions and User Assistance to Fitting Your Bike.

Of course the longer crankARM would irritate your knees more.
Get whatever bike you want, but have very short cranks installed. Aim for the shortest you could find, 150 mm are commercially available, and the forum inmate AnthnyG could advise you on obtaining even shorter ones.

In case you can't get the bike with short cranks from get-go, and aim to replace the cranks later on, the type of the bottom bracket becomes a consideration, and it's safer to ensure that it's a square taper in English thread.

Thanks for the great advice. I'm going to my LBS this evening, meeting with the fitter and will discuss your recommendations with him