hi all, i finally stopped talking about it and went out and bought me an '02 fatboy this april. long story short, i've put only 1200 miles on it and had it towed for the 2nd time last night (thankfully i payed the 7 bucks extra for towing coverage on my insurance). if anyone wants to read, i'd appreciate any insight...

here's the details of my bike: http://www.bryanjd.com/harley.htm i've since changed the pipes to ness stackers and changed the air cleaner to a screaming eagle. she is carbeurated.

long story long: 1st time she was towed, my local (and trustworthy) mechanic said it was carbon buildup on my plugs. so i thought, ok, i need to be more careful with my choke (my only prior experience was with fuel injected bikes). that was after about 800 miles. last night, the same thing happened. i rode out to the mall, no problem. when i go to leave, i let her warm up for about 30 seconds, i go to pull away and she quits, and will not fire after that. i've got more than half a tank of fuel, and this is the same way it happened before, so i'm thinking it's the plugs again. i took the plugs out today and sure enough one is covered in black soot. so i run down to the shop, pick up two new sets (i've now learned to carry a spare set). i replace them, but no dice. still won't fire.

any issues i should be aware of with the engine work that has been done to this bike?

i'm new to working on engines, but pretty handy and willing to try some trouble shooting if anyone has any ideas. i'd hate to trade her in, but for 17 grand i want a reliable bike...

any help will be greatly appreciated,
bryan in florida

ps - i'm posting this in the tech section, too

 

Sounds like the first thing it needs is a remap. Should not carbon up that fast. Maybe some hotter plugs too.

 

Sounds like a tuning issue.. Pretty good indicator is if you're fouling plug problem happened after you did the exhaust and air-cleaner swap. Maybe running way too rich, even if choke isn't engaged.. Possibly? An overly rich situation, like the choke/enricher circuit will cause plugs to foul.

I'd get it into a shop to a tech that can properly tune your carb to your pipes and air-intake.
If you ride it like this.. keep extra plugs on you.. I can imagine towing it is 1. expensive and 2. a royal pain.

Good lookin' bike by the way.

 

What you need is to have your carb rejetted , this is a common thing to do when changing pipes or air cleaner. Take it to a dealer and have it done , not too expensiveand your bike will run right .

 

Take it to the trusted mechanic. Probably needs a carb adjustment if it is carboning up that fast it's probably a little rich. Since you have a high flow a/c and said you are more careful with the enrichener now I would guess you may be runnin a little rich.

 

First we all will suggest buy a service manual.

It takes fuel, air and spark.

Pull a plug wire and insert a screwdriver into the boot. Lay it close to the engine and turn it over. You should see and hear the spark.

They make a spark plug tester that keeps you from getting zinged while doing this. Check both cylinders. If you don't have spark it could be the coil. Or it could be the signal to the coil. Thats where you need the manual.

If you have spark then it's fuel delivery. It could be to much or not enough.

Try to crank it for a few seconds then pull the plug. Is it wet or bone dry.

 

You need to find out why it is sooting the plugs. Check the air filter, make sure no blockage. If that is good. check jetting in carb. Thats a problem buying a modded bike. You can only hope all the work was done correctly.Check that the jet sizes jive with what should be instaelled with the High compression pistons, pipes ,etc.I have seen Harley shops Rejet too far on the fat side due to inexperience. If Jet sizes are close and it continues to run rich youshould probably go deeper into the carb and check for problems, Neeedle size,position, diaphram condition etc.It sounds like amixture problem to me, but I can only guess from hereproblem to me. How did the bike runwith you?How did you ride it? Was the choke parlty out?You could have an ignitionproblem also, but the black plugsare a sure sign of too much fuel.If your not able to trouble shoot this,you might be better served to locate a good tuner and let him look at your bike. Good Luck!

 

Crap. Pays to read and understand. Sorry - Rejet the carb (not FI), like the learned, attentive people here have suggested.

 

Are you sure it's fuel or could it also be burning oil.?Bad valve guides and worn out rings will cause build up like you describe .To foul the plugs that quick it seems like it would be running so fat that it would load up and die all the time.

 

First thing I thought of.When changing pipes a rejet is a must