carb coughing???

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agentpineapple
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Re: carb coughing???

Post by agentpineapple »

another thread derailed by the medalsome middlelands duo.... :lol:
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lloydie
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Re: carb coughing???

Post by lloydie »

agentpineapple wrote:another thread derailed by the medalsome middlelands duo.... :lol:
It's the water up here :-)
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agentpineapple
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Re: carb coughing???

Post by agentpineapple »

lloydie wrote:
agentpineapple wrote:another thread derailed by the medalsome middlelands duo.... :lol:
It's the water up here :-)
well take it out of the water, put it back in your pants and zip up your jeans..... :wink:
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Virt
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Re: carb coughing???

Post by Virt »

:lol: :lol: :lol:
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VTRDark
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Re: carb coughing???

Post by VTRDark »

:lol: :lol:

You are totally right Lloyd :plainsmile even after a good tune up it can occur from time to time. I think that's the nature of the game with cv carbs especially these big fookers. Mine where spot on during the Summer but since then the weather has changed and I have put the baffles in as there's no packing :eek2 (I was going deaf :lol: ), I've also removed a few rivets in prep for re-pack so mine are coughing a bit to begin with on initial warm up period but perfectly fine once up to operating temps.

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E.Marquez
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Re: carb coughing???

Post by E.Marquez »

lloydie wrote:
cybercarl wrote:
Yep run it a little rich and fit a +4 ignition advance and a fuel pump
Explain yourself young man. :lol: :Ball Kick: (:-})
From what I've read and done there's many old wife's tales on how to get not to do it .
Some work some don't even with the carbs set up perfect it still did it now and then .
Yes cleaning balancing the carbs and setting the tps helps as dose a full service but it will still happen now and then .
If you've managed to stop it from doing it great
Or I'm just talking nonsense again :wink:
I suppose i should qualify my response...

The OP posted "Ok brainiacs!!
Every now and then when either sat stationary or slowing down i can hear what sounds like the carbs coughing and the revs drop!!
Any ideas??"


To me, that was not describing that once every few months, when things are just right (wrong?) and you get a carb fart.
To me the OP was describing a consistent, and often occurring issue.. And that is what i was responding to.

If the SH in question is farting back through the carbs often and consistently,. it is not running or set up correctly. Nothing to do with "wives tales" :whatever

If it is a once in a great while,, after a rev though the gears and a quick complete shut down of throttle, coasting to a stop and with a small blip of the throttle as your passing a copper it farts once on the way to normal smooth running as you slide by in 3rd gear at 20KPH... :mrgreen: Then sure, thats normal :thumbup:

Or maybe it's just a OK think and your bikes fart a lot more then US ones :biggrin

(Actually, seriously.. I do wonder if it is something different in Non US import bikes....ECU ? Timing? Environmental gear you have on yours?

It seems to be less an issue (or at least discussed) on US bikes after they are De PAIRED, tuned, TPS set, carbs synced it just occurred to me it might be something different in the physical difference between a US SuperHawk and a UK Firestorm?
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Jamoi
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Re: carb coughing???

Post by Jamoi »

The Uk Firestorm has bad teeth, is overly polite and pronounces tomatoes differently to the US Superhawk...?

Just a thought :wink:

I think the US have the pair system from early on, whereas we got them on the later model?
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VTRDark
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Re: carb coughing???

Post by VTRDark »

Environmental gear you have on yours?
:confused What's that? or maybe this is a US/UK dialect thing.
I think the US have the pair system from early on, whereas we got them on the later model?
There's also a few other subtle regional differences. I suspect the carb needle profile differs slightly as they have different numbers on the needles. Also the US bikes seem to have 45 pilots as standard whereas ours was only the first couple of years and then they where increased to 48's. Then there's the D type head mixture screws which are capped off to go along with the US emissions control.

As for the carb cough/fart, if it's the odd time now and again then don't worry about it. But when persistent it's not (for want of a better word) normal. The two things I have found to alleviate it the best is to balance the carbs and set the TPS to 500. Dialling in (jetting) the carbs is always a good thing to do and it helps but I don't believe this is directly related to the cough unless it's overly lean, hence checking for any intake or exhaust leaks. It's more of a timing thing than fuel! Hence the TPS helping to alleviate it.. Which brings me back to checking the timing and valve clearances. Especially if you have high mileage or don't know the history of the bike, Previous CCT failure for example! There's not much point in spending time dialling in carbs and then if required adjusting the timing and/or valve clearances later, otherwise the carbs would need adjusting again to be spot on afterwards. It would be like painting a wall, then filling, then having to paint the wall again :lol: It's the right order to do things in. Even more so if you don't know the bikes history :wink:

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