250-500cc Top end rebuild intervals

Recently bought a new 2011 WR 300. And was wondering what the general hrs for top end rebuild is? My old bike was a WR 200 Yamaha that was quite long lived I used to put a fresh top end in once a year. Imagine the husky would be similar, I do enduro style riding with a fair bit of high speed and hill work. I ride hard but look after it I use Motul 2 stroke oil and Motul engine oil changed every 400 klms. I change air filters every ride, and upgraded to a uni filter. Would like to hear from other owners of WR 300, also bottom end life. Cheers!

80-100 hours depending on how you ride it(revver or lugger). bottom end havnt done yet but reckon 200-250 hours

I mad around 100 hours on my 2010 300, and never changed anything. It had perfect compression when i sold it, and i rode Enduro and WOT iceracing for 2 winters with it, with high comp head . I guess you can make 200 hours enduro before you change piston. Very good quality the Vertex piston:=)!

Johnny