I found if my knees were too bent, or seat too low, my knees could bother me. Set seat to my other nonebike height and it was better.
Also with assist found I wasn’t working the leg muscles enough, fluid could settle in the leg tissues. Believed called edema, which would also effect my knees.
lay with your back on the floor and legs up a wall, helps with knees to reduce swelling. If it helps you have found your problem.
I tore an ACL and never had it fixed so have to be careful, not sn experience I want to repeat
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