How well do stock cranks for 04/05 450R's hold-up to big bore kits 480 or 500cc?

[yfz450admirer]

I was thinking about going bigger on my piston. I have the stock crank. Do the stock cranks hold up well to big bore kits?

[venom450r]

My stock cylinder/stock crank 480 has held up fine for a little over a year.

[BlaineKaiser450]

you should be fine. just do the updated crank while its apart

[drgnerth]

The problem with the 04 and 05's is the crank bearings not the crank. The only thing that would mess up the crank is running low on oil or running wide open alot, which can cause the rod bearing to go out.