If yamaha would learn how design and build a frame properly this wouldn't happen so often. My first frame was totally fucked, i got a factory replacement, and after my 3rd gear pinned crash into a ditch, it's ever so slightly tweaked in the front. I don't know about the newer yamahas, but the YFM frame is really built like ****. The tubing is too thin, there's little spotted booger welds everywhere instead of a good bead, and it's not gusseted at all in some of the stress points, like at the lower rear a-arm mounts, which is where mine is now bent. Mine is so slight that you have to get out the tape measure and look closely to notice it, but it shouldn't have happened at all. The best bet is probably to get a replacement frame, and get some gusset plates welded in before you put the thing back together. That's something that yamaha should have done themselves to begin with.