I have a 2001 xr650l. I put on the supertrapp quiet core and a k&n air filter. I rejetted from 152 to 155. Plug reads slightly on the lean side of chocolate. (more tan than white) Bike runs very good. I would have gone to 158 except that I was told these bikes were designed to run really lean. I'm only questioning my decision after reading other posts talking about 165 jets. Question: Given the plug reading (done WFO through the gears and then killed and checked) and the fact that it runs great, do you think my slightly lean reading is fine?