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Fuel Problem?


brownm

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My '97 XX just started experiencing a stumbling just off of idol yesterday. It cranks up and idols just fine. Once past the stumbling, it runs pretty much like normal while cruising along without any noticable other issues. This is now occuring every time I have to stop and go from idol now. I noticed when I went to park it back in the garage that it smelled like gasoline was pouring out from somewhere, even though none was present. It has sat in the garage for a couple of weeks since the last time I rode it though. It only has about 4,900 miles on it over the 7 years I've had it. I'm usally pretty good about cranking it up and riding for at least 5 miles at least once a month when I can. Could this be as simple as maybe a fouled plug or is this the sign of needing the carbs overhauled? :sad:

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If I understand you correctly, it stubbles just off of idle as you take off, then everything is fine.

If so... more than likely it's your tip-in fuel cerciut in the carburetors and they require a little cleaning.

It's a common problem on carbureted bikes that don't get ridden enough. Seriously. The Tip-in cerciut is always exposed to the air, so it often forms a dried up residue around the port, when the vehicle sits stagnet for extended periods.

I would try running some BG-44K through it and if that doesn't work, take the air clear out and spray some SeaFoam carb cleaner through the venturi's.

Good luck.

PS. another thing you might want to put on the top of you list, is a bottle of fuel stabilzer for those winter months. :wink:

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I had exactly the same problem. There was crud in the low speed jets.(which may have come from stale gas) This caused the system to lean out just off idle and stumble. Once you start running on the needle and the main jets, it runs just fine again.

I removed the float bowls, and blew out the low speed jets. I added some fuel system cleaner to the gas.

This fixed the problem for a while, but I think the fuel system cleaner stirred up more crap, so the problem returned after a day or two.

The cure was to drain the fuel tank completely, (I went for a long ride, and came home with the system seriously into reserve. Then I removed the tank and the petcock assembly and drained the remaining fuel)After that, I cleaned out the float bowls and blew out the low speed jets again.

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Almost forgot...

...if you run the BG-44K through a tankful make sure you run it through a tankful. You don't want to let it sit in your carberators for long periods, as it will even start to soften the rubber seal inside. If it's left to long it may even eat holes through diaphrams.

Strong stuff... that's why I like it, I have never had to take a set of carbs apart yet, after a couple of treatments. :grin:

I run a tank of the stuff through my Bird twice a year, just to keep it all top notch. :wink: Carberators, Injectors , Valve seats, Pistons, fuel pumps... it helps keep it all clean.

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I don't know about going with this super hard stuff, but run some regular fuel injector cleaner through the system and you may clear it up just like that. Also be sure to always keep a full tank of gas when not running the bike otherwise you're risking a rusty tank.

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Almost done with the disassembly and should have access to the spark plugs tonight. Since I'm this far, I might as well go ahead and blow out all the hoses, drain the bowls and clead out as much as I can. Does anyone have any pictures or drawings of the floats and low speed needles? I don't want to disassemble more of the carb's than I have to.

PS - You have all been a really big help. I appreciate it...

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You only have to remove the Bowls.... spray everything with carb cleaner, blow it and all the little orifaces out with a little air and put her back together.

Additionally, there isn't another good fuel treatment out there, in my book, the rest of them are garbage.

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We're up and running and stronger than ever! In a nutshell, when I went to remove the plug from the number 1 cylinder (left to right) I noticed it was only hand tight. The remaining three were just over hand tight, maybe 1 ft./lb. of torque. :?: Unbelievable!!!! :evil: Who ever installed these should look for another profession. Needless to say the 1# plug was fouled and barely emitting a spark at all, not to mention the compression loss it was experiencing. All plugs have been replaced with new ones. Also, the 1# carb bowl had small amounts of debrise as well, I'm sure due to the lack of proper fuel flow rate. Remaining 3 bowls checked out clean. Also gave it a fresh oil and filter change just in case some raw fuel got by the rings in the non-firing cylinder. I will, however still run the BG-44K through it just to clean everything else out. I would like to thank everyone for their input.

THE BEAST IS BACK!!!! :grin:

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I've never seen or heard of the BG-44K. Where is it and how much?

I wish I'd caught you with the carbs out. I would have told you to drill the slides, and turn the pilot screws out 2 and 1/2 turns. Big improvement.

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$24 for one can.... that treats 20 gallons of gas. So if you have a good storage container, like a glass jar or something that has a good sealing lid, one can is a years supply for the bike.

Or you can just use the rest on your car like I do. :grin:

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Is there any carb tweaking that might help reduce/eliminate the infamous 6-7k flat spot?

Not really tweaking, but I did a K&N (Dynojet) kit on my bike, and now it has a MONSTER midrange. You know that power that comes on at 6-7K rpm? Now it hits more at 4-5K, with no flat spot. This is how they should have come from the factory!

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Is there any carb tweaking that might help reduce/eliminate the infamous 6-7k flat spot?

Not really tweaking, but I did a K&N (Dynojet) kit on my bike, and now it has a MONSTER midrange. You know that power that comes on at 6-7K rpm? Now it hits more at 4-5K, with no flat spot. This is how they should have come from the factory!

Did you just do the jet and filter replacemnet, or would I have to go after-market cans too?

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