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Discussion Starter #1
Let me know if I'm troubleshooting this correctly?

Symptoms: Bike starts, runs for a few minutes. When the temp gauge starts to move (the bike starts to warm up), the bike needs MORE choke to keep running (to me, this means less fuel flowing, thereby needing less air to keep the proper mixture for detonation). By the time its almost at operating temp, it stalls and will not start again.

Previous owner had the bike since last June, and it was running fine until just a few weeks ago. He said the carbs leaked and it would just shut off on him. When I changed the oil today, there was more gasoline in the crankcase than oil. I disassembled and cleaned the carbs, checked the float valves for debris, checked float height, cleaned/checked the pilot jets, etc, and reassembled with new float bowl gaskets. There seems to be no leaking at all from the carbs now.

I think either I have a problem at the petcock, or maybe the tank's vent tube is getting pinched under the seat and the vacuum effect slows the fuel flow after while? I have to recharge the battery now anyway, but I have no doubt it will start later on; its just a matter of how long it will keep running.

I'm thinking the petcock should be the next thing to disassemble/check?
 

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Discussion Starter #4
I know the air filter is fine - its a brand new K&N. I'll just go ahead and pull the petcock when I get home from work tonight. (That doesn't sound right.) ::)
 

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Discussion Starter #6
Yeah, the K&N was in it. I just cleaned and re-oiled the filter before putting it back in. No real changes since the last owner had it running fine (last summer). He said there was a flat-spot in the powerband, but its down around 2-3k, so its probably not worth re-jetting at this point; maybe once I put a new exhaust on it and rip the airbox out altogether, then I'll re-jet.
 

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Bravo12 said:
Yeah, the K&N was in it. I just cleaned and re-oiled the filter before putting it back in. No real changes since the last owner had it running fine (last summer). He said there was a flat-spot in the powerband, but its down around 2-3k, so its probably not worth re-jetting at this point; maybe once I put a new exhaust on it and rip the airbox out altogether, then I'll re-jet.
Not rejet ..... adjust your pilot screws 2.5 turns out (located under carbs).
 

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Discussion Starter #8
Oh yeah. I still gotta drill the caps off! Looks like they've never been touched in this bike's 20-year life.
 

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Discussion Starter #10
I did that on my Bandit years ago, when I went to stage-2 jetting. The stock settings were WAY off - one was 2 turns out, another 4.5 turns out, etc. I'll do that, but I don't think that's the problem I have now, or else it would have done that to the previous owner a long time ago. He didn't change anything since he bought the bike last June, and it was running fine all summer.
 

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Ya didn't clean the pilot jets, you mostly wasted your time.

FOG
 

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Discussion Starter #12
If the pilot jets were that clogged, would it run for 10 minutes before shutting down?

Either way,...thanks everyone. I'm going to check the petcock when I get home tonight. If there's nothing wrong there, then I'll definitely pull the carbs again and check the pilot jets. I think I'm gonna put a Pingel valve and fuel filter on the tank anyway; I've heard about Kawi (and EX250/500) petcocks failing frequently. I'm thinking it was the petcock leaking, not the carbs as the previous owner had said.
 

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Bravo12 said:
If the pilot jets were that clogged, would it run for 10 minutes before shutting down?

Either way,...thanks everyone. I'm going to check the petcock when I get home tonight. If there's nothing wrong there, then I'll definitely pull the carbs again and check the pilot jets. I think I'm gonna put a Pingel valve and fuel filter on the tank anyway; I've heard about Kawi (and EX250/500) petcocks failing frequently. I'm thinking it was the petcock leaking, not the carbs as the previous owner had said.
They fail frequently on the ZG1000 also .
 

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Discussion Starter #14
I got the EX's fuel problem pretty much solved. I took off the vent hose from the tank, which I thought might be getting pinched-off under the seat, and she ran fine today. Well, except for blowing exhaust like a 2-stroke. I think I have some bad piston rings. It's not like the puff-puff that my Bandit used to do; this makes my Bandit look quite eco-friendly. Bad rings would explain why the crankcase was full of fuel the other day, too: sticky float valve + bad rings = fuel all the way down in the crankcase?

Anyway, this isn't a job I can do myself, so it will have to go in a shop. Anybody near Philly know a good shop that may be cheaper/faster/better than the local dealerships? As far as dealerships, I guess I'm looking at either Philly Cycle Center or East Coast Honda (I'm pretty sure they sell/service Kawi's, too).
 

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You may indeed have bad rings but fuel will go past good rings too. It will just take a little longer A typical ring end gad is about .015" enough for fuel to pour through.

FOG
 
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