I have a 2000 YZ426 and was curious if anyone knows if a Wiseco piston has more piston slap than a stocker. I shimmed my valves to spec and checked the timing chain. They seem to be good but I still have a noise that is more than the typical noise these engines seem to produce. Almost like a tapping noise that is getting progressively louder. I even checked the key on the counter balance shaft and it seems to be ok. I pulled the head and jug off. It has a Wiseco 4693M09500 piston. I checked it out on google and it comes up as a standard bore 95mm piston. I will check more tomorrow to see if there are any signs of wear.