Trasmission Experts?

[Steve Robertson]

Looking for some transmission advice. 2 race weekends ago I started having 
some
difficulty getting into 5th. I tried putting some extra preload onto the 
shifter, tried
not preloading at all and finally tired using the clutch. Nothing seemed to 
help and
I only managed to get into 5th just over half of the time. The next race 
weekend it
was even worse so rather than have a big mess I just went down a couple of 
teeth
on the rear sprocket and lugged it around. (good thing our track is so 
short)

I guess I will have to rip the whole motor apart to get to the trani but 
what would be the
most likely problem? Should I be looking for trouble on the gears themselves 
or at the
shift drum and forks? Or somewhere else??? Is there something I can check by 
just going
in through the clutch side or do I really have to split the cases?

thanks,
Steve