Motorcycle Repair/backfiring


I have a 1996 sportster that started having a problem 3 or 4 years ago and gotten worse. after you ride the bike for a long time it runs perfect the entire time but when you stop for at least 30 minutes short stops it is ok when started back up its ok for about 1 mile then its starts loud backfiring and cutting out.
sounds like m80s going off it will do that for about 2 miles then quit and be fine after that.
I put new plugs and swapped the coil and same thing I think the heat is affecting something I tried pulling it in the garage and put a fan on motor one time for 30 min and it was fine I am stumped any help would be appreciated.

There are 2 possibilties here. One is your fuel line gets hot and the bike vapor locks. Once you have fuel flowing it cools off. The other is your ignition is breaking down.
I would start by riding the bike, letting it get hot and try to make it start backfiring. Take the air filter out and shoot some carb cleaner in the carb. If it smooths out or stops backfiring then yo have a fuel problem and need to make sure the fuel line is not getting hot.
If that is not it, then your ignition is breaking down. I wouls suspect its the pickup, located inside the cone of the cam cover. You are not going to have the equipment to test it so you would need to replace it

Motorcycle Repair

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Mike Wells


PLEASE READ BEFORE ASKING A QUESTION!!! I CAN ONLY ANSWER QUESTIONS ABOUT HARLEYS !!! I DONT KNOW ANYTHING ABOUT OTHER MODELS!!! IF YOU ASK A QUESTION ABOUT A NON HARLEY BIKE IT WILL GET REJECTED!!!I have a Harley only shop with 30 years experience located in Ohio. We specialize in complete and total repair, restoration, hi-performance, and custom bike building. I can work on Flat Heads to Twin Cams. Please, dont ask how much somthing is going to cost to fix. Labor prices differ all over te country as well as shop to shop!


If its broke on a harley we can repair it. We do complete restoration from the frame up, engine and trans rebuilding, remapping and custom bike building

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