This is from a book called "The Pilates Edge, An Athlete's Guide to Strength and Performance" by Karrie Adamany and Daniel Loigerot

MUSCLES USED IN THE PROPULSIVE PHASE OF THE CYCLING STROKE
"On extension the gluteus maximus, hamstring and quadriceps are used. As well as the erector spinae.
On flexion the hamstrings, rectus abdominis, internal obliques, external obliques, and tranverse abdominis are used."


How much did you lower your saddle? Did you change your saddle position?When you lower or raise a saddle its sometimes necessary to move the saddle forward or backward.

Do you use clipless pedals? I'm having some of the same issues right now as I'm recovering from ACL surgery and have to use platform pedals on my bike. My therapist feels that my hamstrings are not getting strenthened equally to my quads without the use of the clipless pedals so I have to do more pt oriented workouts for the hamstrings.

I had a new saddle put on and its a little to far forward, after yesterdays ride I really felt my hamstrings. I don't know if thats what did it or the extra hamstring work I'm doing.