dustinsn3485 Posted June 26, 2008 Report Share Posted June 26, 2008 Alright gathering thoughts here.Workin on an older Kawi EX250. Brought to me with the jets drilled just out and running rich.Has pod filters not the stock airbox. I put the stock jets back in. Needle is raised roughly the equiv of one clip via a washer. Battery was junk. Has a new battery now. I've cleaned the carbs in an ultrasonic tank.Last week tuned it and ran great. I had a batt. charger on it while I was tuning because the battery was not putting out enough juice.Last night put the new battery in and attempt to start it. Won't barely run without the choke. Finally get it to barely run without choke, but it revs to like 5000RPM. Also if I give it any throttle it dies. Won't drop back down to idle...This one has me stumped. Why one week it ran perfect and under the same conditions last night it runs so friggin terrible. Thoughts? Quote Link to comment Share on other sites More sharing options...
Todd#43 Posted June 26, 2008 Report Share Posted June 26, 2008 Alright gathering thoughts here.Workin on an older Kawi EX250. Brought to me with the jets drilled just out and running rich.Has pod filters not the stock airbox. I put the stock jets back in. Needle is raised roughly the equiv of one clip via a washer. Battery was junk. Has a new battery now. I've cleaned the carbs in an ultrasonic tank.Last week tuned it and ran great. I had a batt. charger on it while I was tuning because the battery was not putting out enough juice.Last night put the new battery in and attempt to start it. Won't barely run without the choke. Finally get it to barely run without choke, but it revs to like 5000RPM. Also if I give it any throttle it dies. Won't drop back down to idle...This one has me stumped. Why one week it ran perfect and under the same conditions last night it runs so friggin terrible. Thoughts?Just soaking the carbs doesnt necessarily clean them. You may have loosened something up that is now stuck in the idle curcuit. To really clean a carb you have to disassemble it, and physically clean everything.Other than that, check and make sure the floats aren't sticking and are set correctly. Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 Well by cleaning that's what I meant.Completely disassembled them first then put then in the ultrasonic with cleaning chemical and then blew all the passages out with air. Put the stock jets back in set the float, etc. After all that last week it ran beautifully. Now it won't hardly run and I've done nothing between then and now. Quote Link to comment Share on other sites More sharing options...
Todd#43 Posted June 26, 2008 Report Share Posted June 26, 2008 Well by cleaning that's what I meant.Completely disassembled them first then put then in the ultrasonic with cleaning chemical and then blew all the passages out with air. Put the stock jets back in set the float, etc. After all that last week it ran beautifully. Now it won't hardly run and I've done nothing between then and now.You have a fuel delivery issue, most likely a blocked passage in the idle circuit. Sometimes blowing out the passages isnt enough - you actually need to get in there with something to clean it out.You could also have a problem getting fuel from the tank. Check the petcock and the screen. Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 Using a aux. tank. I've already determined that the petcock has an issue.Why do you think it is a blocked passage in the idle circuit? If that's the case then off idle it should run fine. However that isn't the case.And still what I can't figure out is why it would run fine one week, but not 7 days later. If what you think is true, then one week ago the idle circuit was clear. Quote Link to comment Share on other sites More sharing options...
kawi kid Posted June 26, 2008 Report Share Posted June 26, 2008 was goona say petcock screen. did you clean the tank? if you missed something or it hasnt had gas in it for awhile it will lossen a bunch of shit and make problems Quote Link to comment Share on other sites More sharing options...
Todd#43 Posted June 26, 2008 Report Share Posted June 26, 2008 Using a aux. tank. I've already determined that the petcock has an issue.Why do you think it is a blocked passage in the idle circuit? If that's the case then off idle it should run fine. However that isn't the case.And still what I can't figure out is why it would run fine one week, but not 7 days later. If what you think is true, then one week ago the idle circuit was clear.Did you use the aux tank when you ran it last week? Just curious.Anyway, I've seen it before - things run fine immediately after cleaning then suddenly stop. Usually the culprit is a piece of debris that stayed stuck through the cleaning process only to get loose afterwards and end up where it shouldnt.Also, keep in mind that the idle circuit doesnt just "shut off" when you turn the throttle. Its progressive..it takes time on a vacuum slide carb for the other circuit to raise the slide and run. Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 Right I understand. I've just never experienced that with all the carbs I've cleaned.Yes aux tank was used last week as well. Quote Link to comment Share on other sites More sharing options...
Todd#43 Posted June 26, 2008 Report Share Posted June 26, 2008 Right I understand. I've just never experienced that with all the carbs I've cleaned.Yes aux tank was used last week as well.The other thing you could check is the diaphram on the slide. Sometimes those just "give up" unexpectedly. Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 They appeared to be fine. Same with the air cut valve, which I thought may be suspect. Quote Link to comment Share on other sites More sharing options...
Todd#43 Posted June 26, 2008 Report Share Posted June 26, 2008 They appeared to be fine. Same with the air cut valve, which I thought may be suspect.I'm outta ideas. Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 I'll check the idle circuit again, but so am I. It's so weird. Quote Link to comment Share on other sites More sharing options...
justin0469 Posted June 26, 2008 Report Share Posted June 26, 2008 Just since everyone else is out of ideas, did you roughly sync them? I just remember rebuilding the carbs on my 94 RF600RR. That sucked Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 Sync is good. thanks for the thought. Quote Link to comment Share on other sites More sharing options...
zerocrash Posted June 26, 2008 Report Share Posted June 26, 2008 Maybe the carburetor belt needs adjusted Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 Maybe the carburetor belt needs adjustedThat could be it. Seriously, I didn't have this much trouble with any bike I worked on there at the shop. Even that friggin BMW Bill made me do the clutch on... Quote Link to comment Share on other sites More sharing options...
zerocrash Posted June 26, 2008 Report Share Posted June 26, 2008 And I know how much you loved doing that... Quote Link to comment Share on other sites More sharing options...
dustinsn3485 Posted June 26, 2008 Author Report Share Posted June 26, 2008 Well it wasn't two weeks later I quit...That was coincidence actually. Quote Link to comment Share on other sites More sharing options...
John Posted June 26, 2008 Report Share Posted June 26, 2008 Using a aux. tank. I've already determined that the petcock has an issue.Why do you think it is a blocked passage in the idle circuit? If that's the case then off idle it should run fine. However that isn't the case.And still what I can't figure out is why it would run fine one week, but not 7 days later. If what you think is true, then one week ago the idle circuit was clear.the running only on choke is indicative of a blocked pilot circuit.did you take out the pilot jets and make sure you could see through them? then take out the screws and spray some carb cleaner in there and make sure it comes out where it should? the only other thing i could think, is that when you put the fuel line back on the petcock you sheared off a piece of rubber and it has worked its way into the carbs and lodged itself somewhere. its probably been floating around somewhere for a week and has finally worked its way down. that is fairly common with EX bikes. it usually lodges itself in the float valve, but it could have been small enough to make it through. id install a fuel filter too if you havent already. Quote Link to comment Share on other sites More sharing options...
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