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abaker300
01-30-2008, 08:05 PM
I've got (don't laugh) a 1979 honda xr185. I've had the thing for about 15 years now. It sat for about 5 years while i was in the marines and the carb was varnished pretty bad. I ran it through a solvent tank and put a new rebuild kit in it, so it's pretty much good as new. I got it back on the bike and it started on the 3rd kick, so I was pretty excited. The problem I'm having now is I can't get it to idle right.
I've tried adjusting the mixture, the idle and the needle clip position (which I honestly am not sure where it SHOULD be since I can't find any specs on it) and I'm still having problems. It will stay running, but at a very high rpm. and when i slowly loosen the idle screw it just dies, there's no in between. I'm thinking the mixture is too rich because when i give it gas it has a delay and then revs up really high for a few seconds before dropping back down.
If anyone could even tell me what the result of adjusting the needle clip should be, even that would be a help since I'm just taking a shot in the dark with it and hoping it runs better after i move it.
thanks for your help!
aaron

CB750F
01-30-2008, 10:54 PM
Raising the clip up the needle kind of leans it out at a higher RPM and lowering it richens it. It really doesn't do much if at all at idle. Try with the clip one from the top first, usually that's where they are at. Did the rebuild kit come with new jets and a needle?

Make sure the slide moves freely in the carb so it's not sticking. You might want to check your float level again to see if it's too high.

iamgumby
02-09-2008, 12:33 AM
I'm no carb expert...but one thing that I ran across was that if you got your float set too high it caused a rich mixture (too low a lean mixture) and a rich mix can tend to run fast and not idle down, or lean out without dying.

Any other signs? Black smoke? Sooty plugs?

xangomoto
03-02-2008, 06:40 AM
it sounds like your float bowl is gummed up. this can cause you float to stick. most of the time this has more to do with the idle being off than anything else. make sure you have a fresh plug and good spark as well.

i really think it is the float because of the situation you are describing with the engine dying with no middle ground. a flooded float bowl will show the same signs. take off the bottom of the carb and inspect the float to make sure that there are no holes in it. that would cause it to sink to the bottom of the bowl. make sure that the float can move free up and down and make sure that the float bowl can effectively flow into the carb. o i almost forgot make sure that the bleeder hose is attached and not kinked shut.