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Discussion Starter · #1 ·
Hi All,
1980 750 LTD with CV 34's carbs.

The bike runs really good, but when you choke it to start it, you can tell #1 cylinder is not firing. So after you start it on choke (and 3 cylinders) the exact moment you take the choke off, #1 cylinder starts to sputter and it fires up and runs on all 4 again. This bike was a revival project and I have had the carbs off numerous times for cleaning, so I figured a piece of dirt was plugging up something, but then I got to thinking, could it actually be running too rich to fire? I mean, with the choke on, could it actually be getting too much gas and when I pull the choke off it leans out and fires?

Thanks,
Andy
 

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Discussion Starter · #2 ·
Anyone have any ideas on this? I posted this and got no replies and have been busy with other things to look into further....

When on choke it doesn't fire, but the instant you take the choke off it sputters, fires and runs good. I think it might be getting too much gas because it drips a bit of what I think is gas out the joint by the cross pipe below the motor.
 

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GHOSTRIDER
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Howdy Andy, Yes it can be getting too much fuel at start up.That with a weak spark,low compression and any number of tuning issues can contribute to the conditions you've described.The drip at the cross pipe can be gasoline and condensate but should go away once the bike is up to temp and running correct. Many factory pipes have drain plugs for that very reason.
 

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Discussion Starter · #4 ·
You are correct, it does go away. BUT, I'd rather fix the cause than just cope with the dripping. I've used the yellow teflon tape to wrap the polyester plugs that are used to plug the pilot jet (the pilot jet actually gets it fuel via internal passageway from the secondary main). They were shruken down and I'm suspecting they might be leting fuel pass by.
 

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GHOSTRIDER
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Well,if its condensate you wont get rid of it because the humidity(moisture)in the air will condense on the cooler surfaces until everything is up to temp. And it sounds like your on the right track with the pilot jet plugs and new o-rings. Ive been out of the loop for a bit and dont know the history on your bike but over sized pilot jets and/or mal-adjusted fuel/mixture screws and even clogged baffles in the pipes can cause the conditions youve described,low compression too can contribute to those conditions.A weak battery and spark can cause the same. Make sure your getting no less than 11.5 volts to the coils during idle engine speeds. Just some things to look at before you shoot the bike.~wink~
 

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Discussion Starter · #6 ·
Oh no, no shooting. She's a pretty girl for being 30 and will be my daily rider until my 550 decides to start giving me fits.

Anyway, I have over 130 psi cold on all cylinders, about 15k miles on the bike. Barn find from a yahoo south of Des Moines, IA had it. Cleaned the carbs about 5 times already, alot of residual crap. Stock everything, including jets. Rebuilt front forks and petcock. I did the WG coil mod and had good spark and voltage. It would start like a champ cold (with choke on), but you could tell it was missing. Turn the choke off and it would sputter, puff some smoke and #1 would fire. Then it would drip a bit after starting and clear up after the choke was taken off and the bike warmed up. Choke was only on maybe 10 seconds at most. I only rode it an appreciable (longer than around the block) once so far, and it had good power and ran like a champ. (that was last fall though) Haven't had enough time on it to get a really good reading of the plugs, but from what I saw it looked ok. The mixture screws were adjusted to WG's spec (can't remember offhand). One oring on the needles were rough, but that was on the #4 carb, not #1. I'm hoping once I teflon tape those plugs up and make sure everything is clean this will go away...
 

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GHOSTRIDER
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Sounds like your on top of it and have eliminated many of the possibilities and like youve indicated, that narrows it down to those pilot plugs. I wouldnt be afraid to use a little silicon on those plugs to insure a seal. If you havent already done so,installing an inline fuel filter will help keep crud from the tank from entering the cleaned carbs. Good luck and do keep us updated.~wink~
 

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i had the same thing hapen to my 1980 ltd. it must be a thing with the 750,s after thay seat for a long time. hay i though that you were in se iowa ? now iam the only nut around hear with the ols kawasaki,s good luck and keep us posted on what you fink. Bob
 

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Discussion Starter · #9 ·
I was in SE IA, but since accpeted a new job back in our home state of WI! So, did yours clear up after some time?

Anyway, I made sure all the jets/passages were clear and put the carbs back on. Same result... once the choke comes off #1 fires. It seemed that it was missing a little bit at idle, but crack the throttle and all and it had power. After it warmed up it idled just fine, firing on all 4 (however #1 isn't as HOT as the other 3 headers). I haven't adjusted the idle screws yet though.
 

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yes mine cleared up nicely. ive had the same thing with one of the headers not giting as warm as the rest and i recleaned the carb in quistion and all seam to be ok now. its nice to be home with all frends and relation. good luck.and if i can help just let me know. Bob
 
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