I have an 05 xr650L and it still has the smog pump on it. As far as I can tell it routes the crankcase gases back into the combustion chamber. To me it appears to be some pathetic attempt to apease the California regulatory bodies that regulate pollution etc. I have read lots of articles on removing it, butit doesn't appear to have any real benefit to removing it (at least that is what I got from the articles), which is why mine is still sitting there. There are kits you can buy to do the block off but I think it would be faster to fabricate your own bits and do it your self. At least that is what I was thinking of doing. Let me know if you end up blocking it off.I was wondering what this smog pump and Charrcoal cannister by the carb actually do, and is it worth it to strip this stuff? If so what is involved with plugging the holes on the cylinder where the air injectors are from the smog pump? Anybody done this and what are the results???:spl:
I pulled offmy smog pump, did airbox mod/w filter, drilled the slide orifice out to 5/32", put .029" shim under needle, 158 main & 55 pilot jet, i also wrapped the head pipe. I had taken off the cannister but later put it back on as it seemed to smooth out the idle. Different bike! Will be putting on a pipe soon but you can always remove the two plates under the muffler to uncork it a bit. Vince.