03 KTM 525 97mm Big bore 540???

Joined
Jan 4, 2006
Messages
134
Likes
0
#1
I just picked up a new project. 03 KTM 525 that's froze. brought it home today, yanked the motor found the head is still primo, either bad crank bearings or balance shaft bearings (I'm leaning toward the crank bearings but I can't be sure until I split the case). among many mods it has a 97mm piston and cylinder, rather than the stock 95mm.

My question......since I'll be throwing a new piston kit in, and I've found a decent stock cylinder..........any problems with the big bore kit as far as reliability, it seems I've seen a few 525's with thrown rods and the parts are extremely close if not identical to the 450, so does that extra weight/power contribute to a premature failure of an already weak design. ALSO, any notorious problems with the 525's, things to keep an eye out for when it's apart?

P.S. Man, timing chain removal and installation is goofy :coocoo: