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Discussion Starter #1
i just got a 95 vn750 when i got it it was not running needed a stator fix that fired it up for the first time and cranks right up idles good ease on the throttle and at around 3000 rpm it makes a weird noise that sounds like it is coming from exhaust and the rpm jumps a little. ready to take it for a test drive but want to make sure it is nothing serious
 

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It could be an exhaust leak if you had the pipes off.
 

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sounds like the cam chains slapping really bad. if they flop enough, it could cause a miss (due to improper valve timing). also, if the chains are slapping, you will wear the sprockets out prematurely

another to thing to check, is all 4 plugs, wires. could have a loose plug, or a wire arcing to ground.

one other thing, if its trying to backfire thru the carbs, it could sound similar to that
 

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Sounds like maybe it's only running on one cylinder, until you get to 3000rpm and then it sounds like the dead cylinder is trying to fire some. Does it pick up rpm on it's own when you hear that sound?

See if one pipe is a lot cooler than the other, have to check toward the front because the exhaust mixes in the 'goat's belly' just ahead of the mufflers.

Could try pulling both plug wires from one cylinder. If it starts but there's no change in power, you have one cyl not firing. If it doesn't start, the other cylinder is the one with the problem.

Another test, but a bit tricky to do sometimes ... the cylinder short test. You remove a plug wire, then with the engine idling, you touch the wire back onto the plug. If the cylinder is firing, the idle will change. No change = dead cylinder. Except on this engine, we have two plug wires per cylinder, so pull both wires, then touch one back to the plug. The big trick is not getting the chit shocked out of you.

Not sure I'm hearing chain tensioners. I think what I heard could be the problem cylinder trying to fire. But it also sounds like what I heard when I had a sticky valve, which is also a possibility on yours. I hear a lot better when I can stand beside the engine. ;)

If it is a cylinder misfiring, it could also be a fuel problem instead of spark.
 

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Discussion Starter #11
ok so I have decided this is the best group of people on any forum I have ever been on...the back cylinder is dead at idle. where should i go from now as far as trouble shooting

again Thanks So much
 

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Remove the spark plugs, clean them up and install them in the plug caps and lay the metal part of the plug on the engine in such fashion to ground it. Then with the key on, hit the starter button momentarily and see if the plugs are sparking. Do not try and start it. Let us know what happens.
 

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Yep, check for spark (both wires).

If it has spark, take note of the color, and see if it snaps pretty good or just sorta lights up. If it just lights up, it will probably be more yellow-orange color.

If spark is good, move on to fuel delivery.

Sounds like it has life, just needs a bit more of something.

You might start it for a short time before pulling the plugs, so you can see if the plugs get wet. (but don't get it hot)

And just for giggles, you could pull the choke on and see how it reacts. Now that I've thought about it, yours sounds like mine on a cold start after weeks being parked. Takes a few seconds after starting to get fuel to one of the cylinders on mine. (after storing) Sounds just like yours at 3000 rpm.
 

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Discussion Starter #14
OK so I cranked it up no choke idled for a little bit back pipe was cold to the touch revved it same problem cut on the choke let it idle for a bit and the back pipe was hot revved it and it was better not perfect but better so I am thinking it is more fuel than spark. I am replacing the plugs because it has 2 different plugs in the rear cylinder i figure new plugs wont hurt lol. so now is it a adjustment issue or does the carbs need rebuilding
 

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I would say it's dirty jets.

As bad as it's cutting off, teardown and clean is probably the only way. If gas won't flow though the jets, you can't get Seafoam to do much.
 

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I thought so. I did it just so I wouldn't have to fight the airbox when I pulled the engine for the stator and balancer. Have never had my carbs off.

Tip: the Uni PK92 filters are less than half the cost of K&N, and some of us are using stock jets, including myself.
 

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Discussion Starter #19
OK just got the carbs off and apart the rear carb was awful so 99.9% sure that is the problem time to soak them now
 

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Discussion Starter #20
Ok finally was able to work on it. Got it back together question is where do all the hoses go I know the 2 fuel line and I know one vac goes to center of petcock where does the other vacuum port go
 
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