Jumping out of 2nd gear

Hi all,
Last year, when my KZ1000 Police was still working, it jumped out of second gear twice. I think there are three probable causes:
1 - I didn't shift right because I'm not used to heal-toe shifting
2 - The gear forks are worn/damaged. Reparable without splitting the crankcase by taking off the oilpan (I hope?).
3 - second gear is thrashed, needs to be undercut or replaced, which means taking out the engine and tearing it down completely. This I really do not want to do.
What do you think? I'm doing a top-end rebuild, and really don't want to strip it all down again.

I will go with either #2 or #3. To change the shift forks, you will need to take off the oilpan and the trans. cover behind the countershaft sprocket(will need to remove the shaft the forks ride on). More time consuming then hard. I'd try that first and if they look alright, pull the motor. Always do the simple way first!