Carb Cough
Former Sponsor
Joined: May 2010
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When you installed the Thunderslide kit in your carb you should have retained the heavy spring for the slide for a heavy bike. The light spring that comes with the kit allows the slide to come up too quickly and allows too much air to come in when the throttle is first opened. If you replace the lighter spring with the original spring you should not experience this problem any longer. I hope this works for you, it did with me.
Thanks,
JR
Thanks,
JR
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Intermediate
Joined: Jun 2010
Posts: 41
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From: California / Sierra
I feel your pain. Mine will do a hick-up only when colder & running just above idle, when going down the road. Since I'm used to it, I can give it a shot of throttle.
When did you last rebuild your carb? Your probably right about an intake leak. If you use a V.O.E.S hose look at that. Make sure that plug you used when you took off the vacuum petcock are still sealing good.
A bit of info may help us. How many miles on bike, miles since mods, how long in months/yrs since mods. Did you let it sit for awhile with E10 gas in the carb?
When did you last rebuild your carb? Your probably right about an intake leak. If you use a V.O.E.S hose look at that. Make sure that plug you used when you took off the vacuum petcock are still sealing good.
A bit of info may help us. How many miles on bike, miles since mods, how long in months/yrs since mods. Did you let it sit for awhile with E10 gas in the carb?
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Intermediate
Joined: Jun 2010
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From: California / Sierra
Putting the choke on with a warm motor absolutely drenches my plugs with gas and increases the idle to the point of WTF?. Current plugs are new, old plugs looked OK when replaced.
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Intermediate
Joined: Jun 2010
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From: California / Sierra
Exhaust tight.
Seasoned HDF Member
Joined: Dec 2010
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From: Coromandel Peninsula New Zealand
What I meant was if you pull the choke on when riding it?
Elite HDF Member
Joined: Sep 2007
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From: Bluffton, South Carolina
Try switching where you get your gas, preferably a station thats has a hose for each grade of gas. When you put gas in your tank from a station that has only one hose, the first gallon or so is whatever was pumped last, usually regular. This cuts the octane down and can make some engines act up. Then make sure your carb is in good condition, are the jets tight, float level right, idle speed set at about 1,000 RPM's, idle air screw about 1 1/2-2 turns out, slide diaphragm installed correctly with no holes, tears etc and are all the psaaages clen and open. It is impossible to properly tune a carb that has something wrong with it.
Next check your accelerator pump to ensure it is squirting a good steady stream. Some times the rod will hang up and you wont get a full stroke, or the check ball may have a little grit caught under it. Any problems with the accelerator pump can cause an off idle lean condition that gives you the "cough". You should also make sure that the slide is not sticking and is closing all the way. Hope this helps.
John
Next check your accelerator pump to ensure it is squirting a good steady stream. Some times the rod will hang up and you wont get a full stroke, or the check ball may have a little grit caught under it. Any problems with the accelerator pump can cause an off idle lean condition that gives you the "cough". You should also make sure that the slide is not sticking and is closing all the way. Hope this helps.
John
Last edited by miacycles; Oct 25, 2011 at 05:22 AM.
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Intermediate
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From: California / Sierra
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Stellar HDF Member
Joined: May 2009
Posts: 2,856
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From: Middle of Kansas
Sounds like it just may be to rich, since it got worse going from a 48 to a 50 pilot jet. I think I would try a 45 pilot, and see if that doesn't help. A 48 is a pretty big pilot jet. My 99 had a 42 stock, and I replaced it with a 45 with K&N air cleaner and drag pipes. The 45 is plenty big, and really works well, along with a 180 main.
Seasoned HDF Member
Joined: Nov 2009
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From: Farmington ,MS
I sprayed carb cleaner on the intake manifold and could not detect a leak. I put a bigger idle jet in (48-->50) which made the problem worse. Putting the old one back in calmed it back down. Leaning or richening the fuel mixture has no effect. Plugs look fine.
Whaddya think?
Whaddya think?
Sometimes ignition problems will mimic a carb problem...since you have richened the mixture and tried the carb cleaner..check the ignition. I have seen the nuts on the primary wires come loose on the coil...causing those exact symptoms. Also if the ignition sensor is going bad...they usally act up when hot.
