I recently upgraded my 2000 softail heritage classic twin 88 to the S&S cam gear kit with 510 cams. Thought the mechanic would have jetted the carb but he didnt and wants more money to do it. I need to know what size jets are needed. It is not wanting to idle right, pops through the carb when slowing down and then accelerating and at stop lights when accelerating. Bike has 40K miles and the carb has never been opened up. Runs fairly decent when its hot out but on a cooler day its a pain to drive.

 

That is a tough 1 to answer as it depends on many things. Exhaust head pipes and muffler, air cleaner and back plate and which carburator need to be defined. Basically there is really no canned answer. Most people will work with jets to get to the right settings for their build. Assuming you have a CV carb, a needle change may be all you need. Describe your build and how it is running in terms of idle, mid range, and wide open throttle.

 

it is popping thru the carb at various times as well as surging when running at slow speeds in 1st and second gear. Additionally, it wont idle right until it is fully warmed up. I took it in had the S&S 510 cams put in with new lifters, pushrods and bearings. It was running differently so I had a thunderslide kit put in. Still running rough at idle and slow speeds. Someone mentioned that I need to rejet the carb but unsure of what jets to get to match the 510 cams. Mid range and wide open are good to go. I have no problems running in 1st thru 4th cracking the throttle. It has a good response there.

 

Sounds like the slow jet may be lean. Try bumping it up a size. Not sure what slow jets you got with the Thunderjet kit, but see what's in there and go up a size. I'm pretty sure Dynojet jet numbering system doesn't match the HD/Kehin. If all else fails try a 48 slow.