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Discussion Starter #1
:baby: When bike,'86 is idling,front cylinder feels warm,while rear cylinder feels cold. When I take off,bike lacks power until I rev it up and around 5k,it kicks in and starts working great. I will change plugs saturday.I was thinking about spraying gumout through rear carb to see if maybe something is blocking jet.I already have seafoam in tank.Battery is probably weak.I will charge saturday also.Air filters are clean,Hose cut off at 45degree angle,still in need of carb sync.Tried homemade manometer,but rear cylinder tried to suck in the fluid from manometer. Any advise?????:notworthy
 

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HAWK
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If the rear carb tried sucking in the fluid there was alot of vacume or almost none on the other one.
That is a good one. Maby a jet pluged.
Will the rear fire with the choke on?
Have you checked Spark?
 

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Discussion Starter #3
Yes, I checked spark and it seems ok.Also, when choking,seems everything is fine.Maybe something clogging carb.I rebuilt carbs,but maybe something got in there.
 

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HAWK
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The choke will richen the mix and keep it running if the pilot jet is cloged.
That might be your problem.
 

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Discussion Starter #5 (Edited)
One time, I put gumout in carb through drain hole.The bike ran like it was brand new.I just dont want to damage any rubber.When I did carb pull, I had to replace rear carb vaccume diaphram.It had a tear in it.Gumout is great,but it must not sit for too long.Maybe 5 minutes.I once read no more than 20 minutes. Just please,dont make me pull the carbs again.It was awefull.Not really,just different.I havent given the seafoam time to work yet,as it has been -15 degree's here. Question, isnt the pilot jet for idling only?
 

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HAWK
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Idiling and low rpm, I believe.
Over 5k runs fine though. That's interesting.
Vacume is still running through my mind after you said with the manometer.
The right carb runs the rear and was trying to suck up the fluid.
 

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Discussion Starter #7
It could be as simple as a spark plug. Sometimes, a cylinder wont work,but when you rev it up, something kicks in,and it works.When I am going about
40mph,I hit the throttle lever a few times and all of a sudden,she lunge's forward,ready to go and does fine.Also,my carbs may be so out of sync,there,the problem might be.
 

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If your rear carb was sucking all the fluid out of your manometer then your carbs are definitely out of sync. The carb sync screw adjusts the vacuum in the rear carb only - that is, you're adjusting the vacuum to match the vacuum of the front carb. Because you have so much pull in the rear, turn the sync screw to the LEFT - theoretically that will reduce the vacuum, and bring it more into line with your front carb. I'd suggest trying that first (since that's clearly an issue), and at least eliminate that as the source of the troubles.
 

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Benjammin'
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Bike woes....

I won't discount the stuff about the carbs out of sync and jets being clogged as I don't have a clue about any of that stuff. But, I do know a weak battery in our bikes will make it do funny things running. First off, if you don't have a gel or MF battery- get one. That maks huge differences in the bike's runnability. Plugs are also a good idea. Would be best to put both in at the same time because a weak spark or miss caused by a problematic battery will foul new plugs just the same as the ones that came out of it.

My $0.02.
 

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HAWK
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I believe what he was saying is that if you have a bad batt you can get a week spark which can cause your plugs to foul.
Not saying that they will, just that they can.
A week spark will not burn all the fuel and will leave carbon in the cylender and on the plugs.
I hope that is better, Thats what I got out of it.
 

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Our bikes are notorious for electrical problems. The normal wet cell type batteries that some of us use are prone to problems that happen when the fluid is not maintained or they sit too long and have lower cold cranking amps than normal. If a cell goes bad, that is that much less power to get the bike running. You may want to test the batteries output under load and see if it is within normal range 12.5-13V or so.
It may be a combination of the battery and the carb sync issue. Try the carb sync first and if that doesn't help, check the battery. If it needs to be replaced, get a maintenance free (MF) battery. No more checking fluid levels every week and no more acid spills or hose routing issues. I currently have a normal wet cell battery in mine but as soon as it needs to be replaced, it will be with the MF type. They cost more but the relief of hassels is well worth it.
 

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Benjammin'
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Sky said exactly what I meant to say. Thanks Sky for clearing up my post.

You mentioned that your battery may have been weak and though I have not experienced a weak or bad battery causing one cylinder to miss, I have seen posts where others have experienced it. I was just trying to hopefully help you avoid spending money for plugs that could eventually foul again if they are suffering from a weak spark.

Let us know what you find out about your battery.
 

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hey ssmendez... sounds like pilot jet clogged. sorry. I had same thing on my kz1000.. damn thing wouldnt run til you got rpm's above 2k. then it sounded fine... once the pilot jet was clear i could get the carbs to sync up super easy... I have a post over at www.kzrider.com

I found my way to remove/install the carbs is to pry up on airbox with a 1x2 til I can get a long metal rod to fit under the airbox and over the frame...as a support. Makes an unbelieveable difference in removing the carbs.
 

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Was there ever a solution to this problem??? It really helps to know which suggestion, if any, worked. We can't add to the verses if the problem is open ended.
 
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