| The symptoms you describe seem to be a common problem with the Mikunis - the bog is caused by a hesitation in the fuel delivery due to a sudden vacuum drop when the throttle is applied ! Hoss2k4 from Arizona had the same problem on his 2005 Pitster and it still persisted even after he received a new replacement Mikuni carb from Pitster ! He tried EVERYTHING for months , then tried a Keihin carb off his CRF88 and the problem was solved ! The bike (125 GPX Jialing engine) became super responsive and crisp and clean revving from idle to peak revs - just like a Honda ! He said it chucked wheel stands into 3rd gear instead of bogging like it did with the Mikuni . The pitbike Mikunis are just a bad design for 4 strokes whereas Keihins are well sorted and engineered to suit them . |