I have a 99 sportster, after a ride, I shut the bike off and if I try to start it again anytime soon it won't start... sounds like it's loaded with fuel and will give a little backfire.. if I wait about 20 mins or so after trying it will fire right up again, runs good when it's going just won't start anytime soon after .. I changed air filter and plugs (reccommended by dealership) any suggestions.. poss cam sensor? anyone else had similar problem?

doughboy

 

Doughboy,

Sounds like you are getting a flooded condition or possibly a vapor lock.

Try this, when you get ready to shut the engine off, turn the fuel petcock to the off postion and let the motor run a while longer and then shut it off. Let it set for a few minutes and try to restart, without turning the petcock on, if it does you probably have a float needle valve and seat that is bad and needs to be replaced, under hot conditions pressure can build up in the fuel tank a little and force fuel pass a slightly worn needle valve. You could have a needle float sticking slightly under heated conditions. Also make sure the fuel tank filler cap is venting properly, if not it could be part of the problem as well.


John TN

 

thanks I'll give that a try, hopefully it'll help

doughboy

 

Hey John,

I tried that but it didn't help, thanks for the thought..
I'll have to have someone take a look at it.

 

DB,

Sure sounds like you're getting a vapor lock somehow. I did a little surfing and I did find this on a recall on petcocks, on some 97 and ealier HD's. I was looking to see if a HD could get a vapor lock and will do a little more looking and if I find something else I will post it.http://www.docsharleypages.com/news.htm

Did a little futher looking found this :

Buddy in the Mohave desert had the same issue. He was running S&S carbs and
it turned out to be vapor lock in the carb. After that he gave the bike a
couple good shakes before starting it and that solved the problem.

Also you may have an electrical component that is causing the problem after it is hot and you shut the bike down. Found one instance where the coil was the problem and the owner took a cold rag and cooled the coil down and engine started up, he was having the same problem as you. Whatever it is, there's no doubt it's heat related but fixable.

Not trying to get you totally confused, but at least this gives you some more things to try and I was'nt totally sure you could vapor lock an HD, but I guess you can.



John TN

 

hey thanks a lot John, at least that gives me some places to start looking and some tricks to try!!
appreciate the link also..

thanks