I know what a carb fart is (I think), but I have heard alot of people on here describe them as annoying. My idea of what a carb fart is, is when the bike is first shut down or stalls or maybe during a cold start, you might here a pressure release through the inake. Describing them as annoying makes me believe that same XL's have an issue where they fart all the time. Are there really XL's out there that are so flatuent that they fart just cruising down the road? If so, I feal lucky that mine does not have that problem yet. If there are not XL's out there with such a bad farting problem, then why is it so annoying? It's not like you're farting.

I don't think it's a pressure release.

I actually think it's a small back-fire that occurs with the intake valve open, caused by a combination of lean conditions and/or tuning where the carburetor transitions from idle circuit to the main jet needle.

Tends to happen more when cold.

And usually be associated with opening or closing the throttle....

I know what a carb fart is (I think)
Umm, I don't think you do, going by your description. It's exactly like Kev describes it; it's like a backfire, but out of the carb.

yeah I agree with Kev. My '96 had a bad case of the farts once and it was all due to my mixture. Still to this day if I don't allow the bike enough time to warm up it will cough from the carb. I say cough because it's no longer a fart. I just keep the choke pulled for alittle while and it'll settle down and then I'm good to go.

And BTW the farting doesn't just happen as you're riding along. Like Kev said it usually isassociated with opening or closing the throttle. Mine was fine if I rolled on the throttle gently but give it quick jerk and it would fart. I even had pops and bangs upon decel, come to find out I was leaking at the manifold gaskets and they needed to be replaced.

When most of us refer to a carb fart, Kev's tuned in 100%:geek:geek:geek

In fact, I still have to do my Stage I mods this weekend to get rid of mine!!!

:banana:banana:banana

I don't think it's a pressure release.

I actually think it's a small back-fire that occurs with the intake valve open, caused by a combination of lean conditions and/or tuning where the carburetor transitions from idle circuit to the main jet needle.

Tends to happen more when cold.

And usually be associated with opening or closing the throttle....


That what I what I meant when I said pressure release ie. the pressure from still exploding gas excapes through the intake valve. My bike does this when cold, but I hardly consider it annoying. It would be a different story if it did it alot. It's just one of the quircks of carburated engines. I just find it funny, because years ago, nobody would have given it a second thought. That is assuming it wasn't a constant problem. I guess I just haven't witnessed a really bad case of carb farting (when warm), but even then it used to be intuitive that was a sign that the carb needed to be tuned.

A Carb cough is probably more accurate. The air fuel mixture is too lean and it causes the engine to cough through the intake tract. If the engine is up to normal temps and it does this, it is not tuned correctly. Most cases it is the transition from the pilot circuit onto the needle. However blimping the throttle on a CV carb can cause it because of the way the Constant Velocity works. In some cases it can be cured by turnign the idle mixture screw out another 1/4 turn. Other cases may need the carb seriously tuned depending on what the owner has done already. Carb coughs when cold are simply telling you the engine needs more fuel, thus the reason for the enrichener.

That what I what I meant when I said pressure release ie. the pressure from still exploding gas excapes through the intake valve. My bike does this when cold, but I hardly consider it annoying. It would be a different story if it did it alot. It's just one of the quircks of carburated engines. I just find it funny, because years ago, nobody would have given it a second thought. That is assuming it wasn't a constant problem. I guess I just haven't witnessed a really bad case of carb farting (when warm), but even then it used to be intuitive that was a sign that the carb needed to be tuned.

Funny, 'cuz my GPz750 never did it; nor did either of my CB650's, or my CL450.

However, my friend's '98 NH750 is more cold-blooded than my Sportster ever was when it was bone stock. His NH would DIE :frownthre if not allowed to warm up before given throttle. Even on the enrichener.

So I'm pretty sure it's an EPA thing. 4 little shims under the needles works GREAT on stock or K&N equipped NH's, BTW. :D

It's just one of the quircks of carburated engines.

More accurately, the quirk is that of a multi-cylinder motorcycle engine with a single carburetor.