Motorcycle Repair: 2000 HD Sportster, hd sportster, dyna jet

Question
2000 Sportster 1200C with 10K miles, recently purchased from dealer. The last time it was in shop was to jet carb that previous owner did not have done after changing exhaust. Ran fine for about 100 miles. Now when you start it it has a cough when throttled. When riding a let off gas it cackles the pipes. Runs fine on hiway but sputters at intersection. Sounds like it may have a small miss also. Has fresh fuel and have looked for damaged wiring to no avail.Backfires through carb. Any ideas? Thanks.

Answer
First, pull the plugs and check them. They might be foulded. Sounds like the carb wasnt jetted right. Here is a fix you can do yourself. You need a Dyna-jet kit. It has great instructions and you can install yourself. Should take about 2 hours or less. It will jet the bike right and give you more throttle responce.
Good luck and happy riding
Mike