18-20k miles? youre jokin right o.O bikes engines can make it past 50k with proper maint.

my bike too sometimes will go to neutral when quickshifting from 1-2 usually when my front end is up in the air

and as for buying a diff bike, if you went with honda or yamaha you wouldnt have the problem because there bikes dont have enough power or torque to make it miss a gear hehe