Runnning rough

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Runnning rough

zedx
Ok so had the bike out over the weekend at a friends birthday party is ran like crap cylinder 2 was cold. Pulled the plugs cleaned them and moved some stuff around and it ran beautifully all evening, everyone was love taking it for rips. Trailered it home the next day and tried to start it once again running like crap. The cylinders intermittently go cold usually one at a time only hitting on three.

Pulled the pipes off and noticed that there is no gaskets in there (completely forgot to put them in) so I'm sure they were leaking, could this cause the issue?

Also the carbs were only benched synced could this be a syncing issue?

Let me know your thoughts.
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Re: Runnning rough

TOOLS1
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The only thing that could explain a wondering miss along all 4 cylinders, would be bad gas, or crap in the carbs.
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Re: Runnning rough

zedx
No the gas its new with seafoam in it. Very well could be the carbs guess I'll be taking the stupid bowls off again!
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Re: Runnning rough

Re-run
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Before you pull the bowls off, when was the last time you checked the in-tank filter? Or the in-line whichever you have? It could be plugging up some and causing flow issues. When it does run bad, is it after it has been running, or is it random?

What do you have for the ignition? have you verified the timing is on?

I have seen occasional misses that move around, caused by ignition issues. Worn points can be a culprit.
The ride IS the adventure. The destination is just to get gas!
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Re: Runnning rough

zedx
It seems to be mostly at start up. well at least that's what it was at the beginning. I'm really starting to think it is a fuel issue now. I remember I would spray either into the cylinder that wasn't firing and it would come to life. I will check the inline filter today. The tank was just recently de-rusted could be some residual making its way through.

The timing hasn't been touched since I got it on the list to-do, points are new and within spec.
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Re: Runnning rough

Re-run
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Did you adjust the gap on the points? There is a range, something like .012 - .016 or something like that, can't remember off the top o' me head. I always set it right on the lowest though. What this does is closes the points slightly sooner and allows more dwell time on the coils. If your coils do not have the dwell time they need, then the spark energy will be weak.

This could easily cause missing, even a wandering missing.
The ride IS the adventure. The destination is just to get gas!
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Re: Runnning rough

zedx
Ahhhh that makes sense. They are set at .015 currently, I will adjust them down to the .012 see if that helps. One thing I noticed is one of the points when closed the two contacts do not match up real nice like the other set. they are offset then when open a little further off. Thinking I will replace this one again I may have bumped it when lashing the valves.
Kha
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Re: Runnning rough

Kha
This also happen to me. My #2 cyl wire were bad. Changed it and it would fire but the exhaust wouldnt get as hot as the others. So with the cylinder not firing, the gas in the bowl turn bad and turn green. Ran sea foam through and it help just a little. I just got done cleaning my carbs and now all cylinder is firing nice.
Maybe check your wires and check the gas in the bowls.
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Re: Runnning rough

Re-run
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In reply to this post by zedx
Points to be to aligned and hit flat for maximum contact. The point system doesn't have overly high spark energy and so you want to have everything as even and flat together as possible to maximize what you get.

Also, what gap are your plugs set at? Maybe check them and make sure it is right about .028, any more and missing can start to occur, especially if your spark energy is low.
The ride IS the adventure. The destination is just to get gas!
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Re: Runnning rough

zedx
You know now that I think about it I don't know if I ever gapped the plugs. I put them in last fall and honestly cant remember if I did or did not, just assumed I did. Idiot!
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Re: Runnning rough

Re-run
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if they were typical plugs, yeah pull them out and check. If you put in iridiums, they come pregapped.
The ride IS the adventure. The destination is just to get gas!
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Re: Runnning rough

zedx
Ok over the weekend I did some investigating. I replaced the points fuel line (had a little kink in it) and plugs, Flipped the switch and pushed the button, Boom solved! Thanks guys really appreciate it! Just need to get this street legal so I can quit annoying my neighbors by riding it up and down our street over and over again!