I searched and could not find exactly what I am looking for and I need some help. The bike runs amazing at mid to high rpm's but there is a nasty flat spot at the bottom of the throttle and if you snap it the bike will sometimes shut off. I don't know much about the these carbs other than taking it in and out of the bike is a pain. I check all the jets and they were clean. Someone told me it might be the accelerator pump? If so any suggestions on how to clean? I live in NYC (basically sea level) and it currently has a slip on but that is the only mod. The pilot seems kind of large to me as well as it is a 65. Thanks for any tips, it is my fathers bike and I am trying to get it running right for him.