I have the factory HD carb on my 92 sportster 1200. I just rebuilt it last winter but its starting to act up. I am thinking about just replacing this carb with an aftermarket one. It seems to flood real easily now when i try to start it up in the morning, it runs fine after it gets going for the rest of the day but lately every morning the bikes popping and back-firing it's just embarrassing. I talked to one of the guys at the dealership and he said he has had to put additive in his bike to keep it running right with the gasoline these days. The other thing is it seems to be letting out an oily reside all over the side of my block. Any insight?

 

if you got the cash get a mikuni

 

i got that oily residue that you're talking about too, right under the air cleaner. from what i've read on the forums, i'm pretty sure that's normal.