I've had this issue for almost as long as I've had the bike. My shift pedal would come loose and on some random down shift I'll end up kicking the shift pedal down a few notches. No big deal, just a little harder to get my foot under. When I get home I remove the pinch bolt, realign the pedal, retighten, and ride on. I've done this job 5-6 times. Well, last night I did the same drill again only it didn't work. I found out it didn't work this morning when it stranded me at a stop light in fourth gear. I ended up trailering the bike to work. I took the pedal off on my lunch break and the splines on the pedal are f'd! The splines on the shift shaft don't look to terrible ( it is a harder metal) but they do look a little shallow. I had a buddy take some material out of the split area of the pedal (where it pinches) in hopes that this will allow it to pinch down harder. He also cut some grooves in the pedal to give it a little more purchase on the shaft. Hopefully this gets me home. Has anyone had this problem before? I know I'm going to have to replace the pedal but has anyone come across bad splines on a shift shaft? Btw the bike has 137,xxx miles on it...so it's held up to quite a few shifts.