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My 2002 FXSTD Softail Deuce has been running great until recently. It now has issues starting when hot, like when stopping to refuel, and never had these issues before.
A little history... Bike is well maintained and has had the carb refreshed with new slide and gaskets, as well as being cleaned. Jet, pilot and mixture all stock, never had issues. Since then, I've installed a high flow air filter and had no issues. Then I installed Cobra slip-on mufflers and it seems that I've started to have the hot start issues since then... or it maybe it's a coincidence.
All I know is whenever the bike is hot, like when I stop to gas up on the road, it will take forever to restart. I almost kill the battery trying to get it started. I've tried choke, no choke, throttle, no throttle, etc but I can't get a good start when she's hot. It's getting embarrassing at gas stations.
Any ideas? Thanks.
Last edited by BrianCMM; Feb 9, 2023 at 11:08 PM.
Reason: Spelling, "hot' not "hor"
Sounds like you maybe vapor locking, my son had a Honda shadow (carb bike) doing the same thing, he took it to different rice burner shops and they found nothing, one shop even supposedly cleaned the carb, cost him in the neighborhood of 600 dollars (total), he brought the bike to me to take a look, pulled off the vacuum line and cleaned out the vacuum port with a pipe cleaner, too the bowl off and cleaned it out again, his problem went away, the port where the vacuum line was plugged up and causing vaporlock only when hot.
Sounds like you maybe vapor locking, my son had a Honda shadow (carb bike) doing the same thing, he took it to different rice burner shops and they found nothing, one shop even supposedly cleaned the carb, cost him in the neighborhood of 600 dollars (total), he brought the bike to me to take a look, pulled off the vacuum line and cleaned out the vacuum port with a pipe cleaner, too the bowl off and cleaned it out again, his problem went away, the port where the vacuum line was plugged up and causing vaporlock only when hot.
Thanks for the quick response!
I have cleaned out all the ports and lines but still have issues. I appreciate the post, as it could be anything at this point. It sucks because I've never had any carb issues before.
Still sounds like it is vapor locking. Could be a bad coil too, I have had coils get to hot and stop working, although when they didthat the vehicle would just up and quit working until it cooled down.
Since it started with the new muffler the first thing I would do is remove the Cobra Slip-Ons and put back the old mufflers and see if that fixes it.
You mentioned you put on a high flow filter and now upgraded the exhaust without any mods to the carb.
You may need to re-jet the carb just like you have to tune an EFI bike when changing the air intake and exhaust.
Nice looking bike BTW
Last edited by Hecklerboy; Feb 10, 2023 at 09:00 AM.
A couple of ideas. If it still has the vacuum petcock, that could be causing your issues. When mine was going bad it worked fine when hot but hard start when cold. It was a lack of fuel and also affected the VOES and timing, so that would have been a vacuum issue. This one sounds strange, but I've also had a bad battery ( one cell bad ) causing your type of intermittent start issues, mostly when hot after a gas stop. So worth a check.
It seems like your problems started after the muffler change, so I would, for a test, put the stock ones back on and see what's happening. If it seems the starting issues are a gradual type of change then I would suspect the carb. If nothing changes with the adding of choke etc when hot, then it is likely running too rich to start when hot.
If you start having problems after changes on the bike, it's a good idea to backtrack, and retrace your steps.
Put an old spark plug in your pocket. When it acts up, pull a wire and put that plug on it then lay it on the head. See if it's getting spark at crankover speed. Do that and get back to us....
That year doesn't have a VOES - it uses a MAP sensor on the intake manifold that does (basically) the same thing but in a different way.
Still sounds like it is vapor locking. Could be a bad coil too, I have had coils get to hot and stop working, although when they didthat the vehicle would just up and quit working until it cooled down.
The carb has been completely taken apart and cleaned, float level verified, everything in great shape and clean. I don't where I would look for a vapor lock issue. There really are no vacuum lines on this carb. Maybe I should try shutting off my fuel pet **** when I stop to refuel... although I've never had an issue before and I did test the vacuum line on the pet **** and it works as it should.
I was also leaning towards a bad/weak coil when hot. I have checked the resistance when cold and it's all in spec but I have yet to test the resistance when hot.
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Hot start issues, please help
