Tick over problem

[Kiz]

Hi Guys,
i have a 2000 fatboy, when it's up to temperature and i gun off it struggles to tick over farting and spluttering and there's a strong smell of petrol, yesterday on the way to Llangollen as i arrived in the town it happened and on the way home the same, it also seems very heavy on fuel.

I am told it has had a stage one, I'm running Vance and Hines long shots and a Kuryakyn air cleaner.

Any ideas would be helpful.
Cheers,
Kiz.

[S.T.Chapman]

It would help if you identified wether it is carbed or fuel injection.
If it were carb, it would sound as if the float needle had stuck or was set too high?

[Kiz]

Sorry, it's carb

[kiwidave]

check also connections to coil and coil itself. AND your HT leads.

This happened to me a cple of years back.

At certain revs, spluttering and fuel smell.

Turned out to be coil cover digging into the coil itself and somehow grounding it.

One cylinder not firing/misfiiring, fuel smell is unburnt petrol in that head. This could happen with faulty HT lead, poor connections to one cylinder etc...etc.

Also.....obviously...check your battery earth strap is TIGHT. Really. A loose bolt there can make you think the worst but it's a 5sec fix.

(I binned the coil cover, no more problems. It was just a piece of unnecessary bling anyways.)

[Phil]

If it has a `stuck` or `sticking` needle & seat, try exercising them.
Get the bike running & semi warmed up then turnoff the petcock. Run the engine till it starts to run out of petrol, then quickly turn it on again. Do this two or three times. Sounds odd but it allows the float & needle & seat to fully move up & down. If there is a bit of dirt stuck it can also free it.
I would imagine that if it was running fine then suddenly started that the jets that are installed are ok. However I have seen these symptoms when either the main or pilot jet have come loose on their threads.
Finally before anything else put a new set of plugs in, sometimes the simplest things.........

[Steppenwulf]

Hi Kiz,

Sunday morning I experienced the same thing coming over the Horseshoe Pass, had to give it plenty of throttle to keep it running and she was farting and popping away. I put it down to carb icing, it was ferkin freezing and I didn't have any fuel additive to stick in the tank. Maybe it's just coincidence that we suffered similar problems. I was going to wait until it warmed up before checking out if there was a different reason for the poor running.

[S.T.Chapman]

as its carbed I'd go with phil,
also if thats not the and as you say you are having the problem at tickover two more potential causes, is the an air leak any where on the intake manifold? the easy way to find out is to use the good old wd40, spray from behind on to the 3 joints, result to prove good is that there is no change in rpm or smoke emitted via exhaust, if either occur then you have an air leak, but unless you have moved or changed, this shouldnt occur unless the rubber has perished which is unlikely,
is it the original carb?.

as you seem to have changes made, is it right to assume it has the so called stage one mod fitted to the carb?
if so could the pilot air screw have moved?
did you do it? was it done? if so the carb was released from the inlet manifol.
either way the carb to inlet manifol joint was disturbed so again the wd40 test will reveal this.
and again with phil is the a piece of crud floating about in the fuel bowl.
and finally if all that reveals nothing then you could have an ignition fault.
it could be your map sensor has packed up or more likely the plug has come loose on the top side of the inlet manifold.
or some problem with the ignition module, however thats looking too far ahead and you should eliminate the obivious first before jumping to conclusion's.
fault diagnosis is never useful if you start in the middle and bounce from one theory to another till you do or dont find the problem, start with what you know to be the last thing done to it then work back till you find the cause, its called a process of elimination.
incidently what carb is actually fitted?

[harleyhog]

Hey S.T.
You actually sound like you know what you're talking about there.

[Kiz]

Hi Guys,
thanks for the info i'll try it out and see what i come you with, i'll let you know what i find.

Thanks again,
Kiz.

[CrazyIvan]

Originally Posted by Steppenwulf

Hi Kiz,

Sunday morning I experienced the same thing coming over the Horseshoe Pass, had to give it plenty of throttle to keep it running and she was farting and popping away. I put it down to carb icing, it was ferkin freezing and I didn't have any fuel additive to stick in the tank. Maybe it's just coincidence that we suffered similar problems. I was going to wait until it warmed up before checking out if there was a different reason for the poor running.

I had exactly the same as you a week ago Saturday, first time I've ever experienced carb icing. Even managed to stall at a set of lights which wasn't that cool As soon as the temp rose by a couple of degrees problem disappeared. My circulation took a little longer....