due to the these bikes being so old this will happen more and more a way to fix it would be of course to disasemble the shift case/rods and clean them but a eaiser way would be to simplie take some bug/tar cleaner and clean it off when u ride it hard or after every like 3-7 rides this will keep junk/crud from getting in there and if u have it polished or chromed make sure u get some that will protect the shine!