anybody good with XR's?

[vroom]

Hey guys ... I have a 2001 XR100r and i wanna put a new top end and fmf pipe on her. I know it prolly doesn't need a new piston but i feel it lagging and i wanna invest some money into her... soo... i went to rockymountaintatv.com and i found a weisco piston kit with rings and all that stuff.. but.. what size do i need for a STOCK bore, its not bored out.. do i need it to be? well if i dont it comes in .20 .40 and .60 ... which one is it guys? I'd really appreciate some feedback:)

[lil400exman]

well i know honda xr's last forever between rebuild cause of the good tolerance's they use on the engines. Mine is a 99xr 250 and i have run it hard and even in 1 "halloween 100" its a 100 mile xc race and it still runs well so i dont think its your piston giving you problems. my carb on the bike was junk i called al bakers xr only and got a bigger carb cant rember the size and it helped it alot then i got a cam for it and those 2 things really helped the bike along with e-series pipe i have on there and wiesco pistons are ok i like a vortex or a oem with a nacs piston race port on a 2 stroke but about 4 strokes i have never had to replace a pistion i just know from my r so about what brand i dunno but call xr only under links section here they have a website it think its www.xrsonly.com i cant rember 100% but uhh under links here at exriders his website is there;)

[vroom]

you think its the carb? how much would a new cam and cvarb be .. i cant find it onxr's only :( i hear xrs grind cams all the time

[lil400exman]

Originally posted by vroom
you think its the carb? how much would a new cam and cvarb be .. i cant find it onxr's only :( i hear xrs grind cams all the time
i really never hard of that before man i just know the stock carbs honda puts on the smaller xr's arent real hott for staying in tune and stuff and i know from experince......lol