Hi,

I am new to the sportster world and well the whole Motorcycle world really. I will do my best to explain the issue, and sorry if this is a simple fix that should be easy to find on the web.

I had purchased a 2001 HD Sporster XL883C with approximately 24k miles about 4-5 months ago from family members. I had obtained my license and rode the bike prior to purchase with no issues. After purchase, I rode the bike home (1hour-65 miles) with no issues, and then for a few weeks after. No super long rides, and to and from work.

One night on my way home, the bike began jerk, and backfire super loud like gunshots (not sure if it is from carb or exhaust) anytime I tried to give throttle. I was near a gas station so I stopped and my fuel tank was fairly low took about a full 3 gallons at the time. Started the bike back up and tried to finish my commute but it still jerked, backfired, and lost total acceleration in sperts (i assume is why the bike jerks) but does not die. The bike also starts, and idles with no issues even during the poor performance.

I researched the issue and started by trying to clean the carb. It was a little dirty but not super excessive. I started the bike and rode it with no issues, but it was not a long ride due to rain at the time.

A few days later, I rode the bike to meet my wife for lunch and it rode fine, and even made it on the highway with no issues. I then came to a stoplight an sat for about 3-5 minutes waiting for my turn. Once I began to apply throttle, the same issues as prev. described.

I later found out that the bike does in fact run with no issues/full power when I first start riding for the day, and it is not until I have been riding for 15-20 minutes that I will then stop at a light, and when I take off, it runs poorly for the rest of the time I try to ride.

In addition to trying to clean the carb, I have also replaced the ignition coil based on a recommendation from a friend who had a similar issue. Unfortunately it is still not running right.

I have also found that once it starts to run poorly, if I ease into the throttle during each gear it will not run poorly until certain speeds for each gear. 1st 0-20, 2nd 20-30, 3rd 30-35, 4th 35-45, and 5th will not allow me to really go past 55 once it starts to run crappy. But I can top it out at the beginning of a ride if I want with 0 issues.

Does anyone have any ideas on what to do before I try to have shop look at the bike for me? I do plan on checking the plugs, and replacing them and the plug wires here soon if not tomorrow just as a tune up but since it runs fine at first, I wouldn't think that would be the issue but I am no expert.

Not sure what is stock or not as family members I bought it from are not the orig. owners, and they did not change anything on the bike. Currently it has screaming eagle pipes, air filter, and other chrome additions but I don't think it has any other aftermarket parts or enhancements.

If there is any other information the community needs to help me, please let me know.

I haven't really been able to ride this summer after purchase and it is killing me. Any help that can be provided is greatly appreciated.

 

check your intake boots first please

 

Hi happy,

would you be referring to the rubber gasket that goes around the entrance of where the carb connects? If so it has come off while cleaning but it was a tight fit to put back on and I did not see any tears.

 

yep just make sure there are no cracks and its clamped well this will cause issues of sucking air when hot. Quick way to tell if leaking is spray a little carb cleaner around boots while idling and see if changes rpms.

 

Thanks, I'll definitely try that.

I guess it is possible it's just worn out and does not hold shape well, especially when hot.

I'll update when I get a chance.

 

Ageing nosecone ignition modules on 2003 and earlier bikes are known to start failing when they get hot, like after the bike has been running 15-30 minutes. The same applies to the ignition coil, to a lesser extent.

You can troubleshoot these items using a can of electronics circuit cooler spray. Leave the cover off the ignition module and go for a ride (with the spray can). When it starts acting up, stop and give the ignition module a good spray-down. See if that temporarily fixes it. If it does, the module needs to be replaced. Same goes for the coil.

 

I had same problem. After researching, came to the conclusion it was the Crankshaft Position Sensor. Replaced myself ($60.00 and 10 min.) Have not had a problem since.

 

This sounds about right...I had a similar issue. Mine **** on the freeway at night time though, that was a fun time. Called my boss to use his AAA. Threw a Dynatek ignition in there and haven't had an issue since. Super easy install too.