Nope...in my experience and I've built lots of motors and transmissions. Only one cause for gears jumping out under load is worn engagement dogs on the drive gear of the input shaft and/or worn engagement holes in the driven gears on the output shaft.
The ONLY real fix is to replace the two gears, drive and driven. If you can do the work yourself 80% of the cost is labour. I've split lots of engine cases and if the RC is like most V-twins then unfortunately the top end has become off too.
I've done inline's where you can just flip the motor over remove the bottom case half and re-re the tranny...but in the case of the RC I think not.
Maybe Makis or b.miller could chime in if I'm mistaken about the RC, I don't think it is a cassette type transmission would be nice though.