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Discussion Starter #1
I knew my OEM petcock was leaking. I found out last year when I was doing some investigating of some bogging issues my bike was having.
I bought the petcock rebuild kit...against the advice of several people here...and discovered exactly what they warned me about; that the leaking was actually WORSE after the rebuild.

Anyway, I also picked up one of those cheap Chinese-made petcocks thats designed for the Kawasaki Quads, but fits our bikes. I think it was $10 from Amazon.
So, I installed it today, but I had to make two mods first:
1. I hade to removed the thumb lever and grind it down so that it would flip to "on" without hitting the seam of the tank. 5 minutes on the grinder solved this issue.
2. I had to use a screw-type hose clamp because the main fuel port is smaller diameter than the OEM petcock. Thankfully, I have hose clamps.

First thing I noticed after install was that fuel was no longer pouring out of the petcock when the bike was off. The next thing I noticed was the I didn't smell the stench of gasoline, which was a byproduct of the fuel pouring out of the old petcock.
The third thing I noticed was that the bike started right up and idled/rev'ed smoother than before, even though it was still cold.
This is curious to me since the carb should have properly metered the fuel coming out of the petcock regardless of how much flowed out, yes?

At any rate, I can't wait to take it for a test ride. I might have a small window before the rain comes.
 

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Discussion Starter #2
Okay, as I suspected the running condition hasn't changed. The bike does start easier, but I'm still getting popping and backfiring on deceleration, so I'm going to have to pull the carb, I think.
It was supposedly rebuilt before I bought the bike and everything ran great for the first few months.
At least I'm not dumping fuel anymore. :)
 

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Discussion Starter #4
Yes, I was looking over my previous threads.
Where is the cut-off valve located? Do I remove the carb to get to it?
 

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See it here.
https://www.motorcyclespareparts.eu/kawasaki-parts/motorcycles/vn800-1995/carburetor-581143.aspx
Ref. No. 43028

And yes! You will have to take it off and dissemble. (Be careful with spring that shoots in Your face :beat-up: and don't loose the little o-ring under the valve cover!)

P.S.
The membrane originally should be soft and rubber-flexible, without holes and damages in it. When it's old it gets rather hard and crunchy :D The valve should move freely towards/backwards the spring.
 

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but I'm still getting popping and backfiring on deceleration

that is caused by being lean in the pilot circuit, the fix is to turn the pilot mixture screw out another full turn, (turn it counter-clockwise 1 turn more)
 

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There's a rather simple way to check if a mixture was too lean or too rich. Check Your spark plugs :)
Check the way they look.
Actually You should always check Your spark plugs first. If You have some spares, You can even change them for diagnosing such kind of problems.
 

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Another common issue that could be causing the back firing is a leak in your exhaust, especially where the headers attach to the head. With it running, put a cigarette or incense stick near all exhaust joints to see of the smoke gets blown around.
 

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Petcock

Another common issue that could be causing the back firing is a leak in your exhaust, especially where the headers attach to the head. With it running, put a cigarette or incense stick near all exhaust joints to see of the smoke gets blown around.
,.................................................................

Incense??? Does anyone still use that stuff????

Sorry, I know you are trying to help and I don't smoke, but wow I haven't thought about burning incense in years......

No offense intended....
 

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Incense??? Does anyone still use that stuff????

(At Shores) Sorry, I know you are trying to help and I don't smoke, but wow I haven't thought about burning incense in years......

No offense intended....
My suggestion was for gtrdave43 who is having the issue. I'm sure he is resourceful enough to bum a cig or figure out something else that would create a small amount of smoke.
 

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,.................................................................

Incense??? Does anyone still use that stuff????

Sorry, I know you are trying to help and I don't smoke, but wow I haven't thought about burning incense in years......

No offense intended....
Hey I resemble that Remark:eek:
 

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Discussion Starter #17
An update:

I discovered why my bike was running so badly.
The dual clamp around the hose that mates the carb to the intake manifold? Well, one side got over tightened and worked its way off the hose, causing the hose to be misaligned with the intake and letting in gobs more air than should have been allowed.
I'd read about this very thing, but didn't suspect anything because I couldn't see the bottom of the hose and clamp UNTIL I removed the carb and hose.
I wondered why the ends of the two sides of the clamp were at different gaps when supposedly tightened.

I just reassembled everything and started the bike.
OMG! The thing started right up with no hesitation and bogging and idled perfectly even after sitting for 2 weeks in the cold.
 
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