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Discussion Starter #1 (Edited)
Hey guys, I've done a lot of reading but I can't find anaything about this symptom.

I left my stock '99 bike parked in a lot under a cover for a month. The bike is in Kentucky where it's hot and humid. The bike was left with 1/4 tank. The problem started on the first ride. It started with a normal warm-up but the needle had an occasional tick where it would jump 500 rpm's. After warm-up and the choke closed I went to give it some throttle. When I did this the engine reved up to 4000 and then would struggle to get any higher and would start bouncing up and down between 4-6 grand.

I checked the plugs and they were all normal except the rear right, which was black. I added 4 oz of seafoam to the 1/4 tank and expected a change. It sounds a little low and it is definately running rough. It stalls with a quick pull in the throttle but after moving the throttle will wind the revs all the way up without any trouble.

It used to get ~ 50mpg and since returning it is getting about 30 mpg. I replaced the plug with no change. Again, it idles starts and idles normal. I'm still waiting for the seafoam to work it's magic. There's no telling what the heat did over a month. Help! Thanks.
 

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HAWK
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Do you have the Ears?
If so check the vent tube on teh right side to make sure it is not unplugged or bottomed out.
 

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and the Adventure Cycle
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Wouldn't hurt to give the air filters a quick check too. Make sure the filters are in good condition, clean (but oiled properly), and no critters in them.
And while you're at it, check that the wire from the black plug is connected good to the coil.
 

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Discussion Starter #4
Thanks for the suggestions. Everything seems to be as expected. I believe that all four plugs are firing; filters look good too. It's just running really rough and is sucking down gas.
 

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Discussion Starter #5
I forgot to note that the bike has the coasters removed and it also has a MF battery. Otherwise, is there anything specific that would cause the tach to jump around independent of the engine? Also, would an exhaust leak cause any engine problems like slow acceleration or louder that normal sound? Thanks!
 

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Someone correct me, but if the right rear plug was black (oily?), it's running rich (which might explain the excess fuel consumption - although that's a whole lot of excess).

Just checking: the bike was coastered and you removed the coasters? So now air's moving through your reed valves? Are all the hoses set up through the emissions chamber to the right places (two large ones to the reed valve inlets; one to the airbox (although big) and a small one to the right vacuum port.

Finally, have you sync'd your carbs? It may be irrelevant here, but I do know that the tach will jump all over the place when the carbs are outta sync.
 

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air/ mixture problems

I have just did an ear shave today- and now I have a big prob with my air mixture. I pinched the right vaccum hose to see if it would help at all, and to no improvement, I am started to get a little frustrated. The bike seems to idle very high, yet when I adjust the idle to run smooth, as soon as I start to get the bike going, it seems to revv high again. any suggestions for mynext step? Am I going to have to re-jet the carbs?
 

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HAWK
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Sounds like you have a vacume leak, Check you boots on the carb.
They have a way they need to go or they will leak.
 

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Discussion Starter #9
I have confirmed an exhaust leak in the front cylinder. I hope that clears up some of my concerns. Otherwise, I'll assume you're refering to the black boots that connect to the carbs, Ccspinner? The big 2, or are there more? Thanks for the help.
 
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