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Blake W.
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46 Posts
Discussion Starter #1
When I start to ride as i get the rpms up to around 2 to 3 thousand and am going through the gears the bike has a burp like stall....doesn't backfire just hesitates. Does it in all gears. Any ideas?
 

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Blake W.
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46 Posts
Discussion Starter #2
Will running the vacuum hose from the tee off the carbs under the seat instead of into the airbox cause a problem?
 

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Premium Member
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4,778 Posts
It might be. That hose needs to be in still air. Seems like I saw a member's pic where he put a tiny filter on the end of the hose, which should do the trick.
 

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Linkmeister Supreme
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7,960 Posts
X2 to flitecontrol`s post.^^^
 

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Blake W.
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46 Posts
Discussion Starter #5
Moved the hose back to the airbox but haven't driven it yet. Will post the results soon.
 

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Blake W.
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46 Posts
Discussion Starter #6
Moved the hose and that fixed problem. Now I switched over to NGK iridium plugs and the bike dies when i give it throttle. Sounds like its flooding. What gives?
 

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Blake W.
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46 Posts
Discussion Starter #7
Gonna swap bake in the old plugs and see what happens.
 

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Blake W.
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46 Posts
Discussion Starter #8 (Edited)
ok....it did the same with the old plugs now. Tried turning screws out and in ...made now difference. Starts and idles great but as soon as throttle is turned it wants to die. Was running fine before the plug change. :confused: Also noticed on here something about the gas tank vent hose....I did just put gas in before I started it today. What does the vent do?
 

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2,687 Posts
I think your carbs may need cleaning. I had a similar problem, where it would start and idle but die if I opened the throttle... took off the carbs, took them apart and cleaned the hell out of them and problem solved.

Don't know if you've already cleaned them or not though, this is just what happened to me.
 

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Blake W.
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46 Posts
Discussion Starter #10
Figured that might be the prob so drained them and it runs now. Still has a misfire running up through the gears and wide open throttle.
 

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Premium Member
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4,778 Posts
Sea Foam may help.
 

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Registered
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2,687 Posts
If all you did was drain them, they might still need a cleaning.

Seafoam might help, as flitecontrol says. If that fails, then you should probably take them apart to clean them up nicely.
 

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Blake W.
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46 Posts
Discussion Starter #13 (Edited)
I pulled the jets when I first got the bike and cleaned them. Didn't appear to be clogged or anything but cleaned them anyway. haven't looked at the diaphrams yet or the floats. Might be my next option If I can't work with the air mix screws. Also what is the correct gap for the iridium plugs? can I use stock gap of between .03 and .04? Saw somwhere I think someone said .02.
 

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Blake W.
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46 Posts
Discussion Starter #14 (Edited)
Had to go to 3 1/2 turns on air mix screws. Now runs better but still backfires and sputters. When I open full throttle it just dies completely and have to let off throttle to continue going.. Would rejetting help?
 

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Linkmeister Supreme
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7,960 Posts
I pulled the jets when I first got the bike and cleaned them. Didn't appear to be clogged or anything but cleaned them anyway. haven't looked at the diaphrams yet or the floats. Might be my next option If I can't work with the air mix screws. Also what is the correct gap for the iridium plugs? can I use stock gap of between .03 and .04? Saw somwhere I think someone said .02.
The stock gap as the NGK Iridium plugs are delivered, has been reported to be between .032"-.036". I would not adjust the gap if it is anywhere in the .030"-.040" (0.8-0.9mm) range recommended in the service manual.
 

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Blake W.
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46 Posts
Discussion Starter #16
The gaps are at .035 so they should be good. Gonna try to move the vent hose from behind the right ear back under the seat somwhere and see if that makes a difference. If not I'll pull the carbs and look over diaphrams and floats i guess.
 

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Premium Member
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4,778 Posts
The vent hose in the right ear is where it was designed to be. But it can bottom out against the housing if the end isn't cut at an angle.
 

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Blake W.
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46 Posts
Discussion Starter #18
Have the hose cut at 45 but not in the stock place. had to just run it through the air square air access hole in the ear.....just got it laid in the hole right now. Don't think that should be in the way of turbulant aire but who knows. Sent Lance a PM about maybe jetting but still not sure what the problem is. Next step is a check of carb diaphrams and floats I guess.
 

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448 Posts
I ran into the same problem with my bike yesterday, she starts and idles fine, takes off from a stop w/o any problems, and as soon as I give her throttle she tries to die on me.
I thought it was a fuel issue until I happened to look at the tach, and as it tried to die on me, the tach needle would drop to zero. So mine is electrical related, and your might be as well. So next time it tried to die upon acceleration, look at the tach to see if the RPM's are up or not.
Just a thought.
 
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