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Discussion Starter #1 (Edited)
While under a load my bike seems to idle a little bit rough. Also while riding there are moments where I get like a surge of power like in suddenly has all the power in the world. And then it goes away. Not quite sure what to check to correct this issue is it vacuum, spark or fuel? Maybe I need to adjust the pms screws? It does have the modified stock exhaust. Could that be a back pressure problem. Kinda at a loss here. I am a pretty good mechanic. I work on BlackHawks and I know my way around a vehicle’s engine. Not too terribly experienced with bikes. I see a lot of people talking about ais delete and other mods like big air and pod kits. I honestly just want this thing running. all next week it’s gonna be in the 70s here and I would love to ride!!
 

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Super Moderator "Loose Nut" - Houston, Texas
2001 Vstar 1100 Classic (sold), 2006 HD Electra Glide Ultra Classic
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I suspect a fuel issue. First I would change fuel filter. If that doesn't cure it I would check carb floats. It sounds like you are not getting a full fuel flow all the time. If after you change fuel filter and don't see improvement, check back and several of us are pretty carb savvy and can walk you thru checking float level.
 
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Might be a partially blocked jet. How does it pull with the throttle wide open?
 
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Check air leaks at the intake manifolds,check plugs and see what color they are, Blow out the air cleaner.
 

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Discussion Starter #5
I suspect a fuel issue. First I would change fuel filter. If that doesn't cure it I would check carb floats. It sounds like you are not getting a full fuel flow all the time. If after you change fuel filter and don't see improvement, check back and several of us are pretty carb savvy and can walk you thru checking float level.
When I got it it would only idle and it dumped fuel out of the overflow I took the carbs apart cleaned them and reassembled. It idles great no gas overflow and it revs up and down fine without a load on it. But as soon as I put it in gear and try to go it feels really bogged down.
 

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Discussion Starter #6
Check air leaks at the intake manifolds,check plugs and see what color they are, Blow out the air cleaner.
I did notice I was missing a clap from the air box to carb I replaced all the boots and they fit very snug even the boots from the head to carb I replaced. Could a crack in that weird oval piece that goes from the air cleaner to the air box be the issue? I can seal it up with silicone. It’s at the edge under one of the clamps.
 

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Discussion Starter #7
Might be a partially blocked jet. How does it pull with the throttle wide open?
Still feels a bit dogged down. I would run it in my neighborhood and about half throttle I got a surge as rpms went up then it got a little better but not much. Then shift and really felt dogged down.
 

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When you cleaned the carbs did you take a stripped twist tie and run through the jets? This is a trick people have learned over time, it can make a difference. If the crack is big enough in the airbox it can allow more air than is needed, but shouldn't make a great difference. You really need to look at the plugs and see if they are white. If they are you are either getting too much air or not enough fuel. If they are black , too much fuel, you want them a dark tan to brown in color.
 

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Discussion Starter #9
When you cleaned the carbs did you take a stripped twist tie and run through the jets? This is a trick people have learned over time, it can make a difference. If the crack is big enough in the airbox it can allow more air than is needed, but shouldn't make a great difference. You really need to look at the plugs and see if they are white. If they are you are either getting too much air or not enough fuel. If they are black , too much fuel, you want them a dark tan to brown in color.
i yes I did the twisty tie thing. I will check the plugs. Thanks for the info. It doesn’t smell of gas at all. But the plugs could be fouled. I haven’t replaced them yet. Since it was dumping fuel just flowed out of the carbs. Should have probably been one of the first things I replaced. Basic tune up. Common sense. Especially since I do notknow much of the bikes history.
 

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i yes I did the twisty tie thing. I will check the plugs. Thanks for the info. It doesn’t smell of gas at all. But the plugs could be fouled. I haven’t replaced them yet. Since it was dumping fuel just flowed out of the carbs. Should have probably been one of the first things I replaced. Basic tune up. Common sense. Especially since I do notknow much of the bikes history.
Please check your oil to ensure it doesn't smell like it has gas in it. If your bike was dumping fuel from the overflow, it could be a stuck float which would cause overfilling. Unburnt gas can pass through the piston rings and into the sump. This can be catastrophic as it washes the grease from the engines bearings...
 

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Discussion Starter #11
Please check your oil to ensure it doesn't smell like it has gas in it. If your bike was dumping fuel from the overflow, it could be a stuck float which would cause overfilling. Unburnt gas can pass through the piston rings and into the sump. This can be catastrophic as it washes the grease from the engines bearings...
Oh yeah that was the first thing I did. The moment I got it home. New oil. I bet there was a quart of gas in the oil. Changed the oil then cleaned and repaired the carbs. Then I did a lot of visual modifications and polishing. Now just need to work on getting the thing dialed in. I also replaced the final drive because it had no fluid and what was left of a blown out bearing in the drive. Gonna rebuild the old one so I have a backup. Just waiting on parts to arrive to finish the rebuild.
 

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I also replaced the final drive because it had no fluid and what was left of a blown out bearing in the drive.
just spitballing here... any chance your rear brake is dragging after replacing the final drive?
 
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you could check to see if your gas cap is venting... just trying to eliminate simple things.

also check your intake manifolds for cracks and the orings (#5) sometimes leak with age.
100463
 

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one other thought to add to the other posters... did you sync the carbs after working on them?
 
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Super Moderator "Loose Nut" - Houston, Texas
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Discussion Starter #18
Great to hear. What did you do to get it right?
I took the carbs apart again and did the twisty tie thing to clean the carbs. I thought I cleaned them really good the first time. Guess not because that front cylinder carb jet was clogged big time. Did an extra throughout cleaning the old girl snarls like a monster! Very throaty. Yet quiet at a stop. It’s awesome! Spent an hour out riding around! It was amazing!
 

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Super Moderator "Loose Nut" - Houston, Texas
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Excellent, just remember next time someone posts a similar issues, jump on in and explain how you fixed yours.
 
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