This weekend while on a ride my friends Z400 got stuck in 2nd gear. It will shift fine from 1st to 2nd but will not go any farther. Has anyone had this problem with a Z400 and what was your fix? I was thinking maybe a shift fork, any ideas? Like I said the bike runs and shifts fine from 1st to 2nd but once in 2nd it won't go any higher.

Maybe a long shot, but the guy who rebuilt my bike has a Z400 and he races and jumps it hard and broke 2nd gear a couple times.