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cegan09
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Alright, i'm hoping this is my last thread of this type for a long time. The bike is so close to running properly, but its not. If i let it sit for a while, or cover the carb openings and push the starter a few times to draw fuel through it will start. It will run beautifully for about 5 seconds, reving freely as you adjust the throttle, then it just dies, nothing you can do. Repeat the waiting game or covering teh carbs, and it will repeat this .

I know this points towards a fuel starvation issue, but i can't for the life of me figure out what is wrong. carbs have been cleaned quite a few times. All jets are set to stock. Needles have not been touched by me ever. Floats are set to stock height per the workshop manual (25mm +/- 2.5mm). Idle mix screw set to stock (1.25 turns out). There is fuel going to the carbs, one of my lines is clear, and it is never more than half empty. I do not have in line filters, honestly know where they are if i have them. I'm assuming there are filters in the tank at the petcocks, but honestly i don't know.

if someone can give me an idea of what to check or change i'd be very grateful.

I'm about as sure its a fuel problem as i can be. I have checked spark, have spark. Timing was set in the spring, hasn't been touched. New battery, new coils, new spark wires, new plugs, new spark caps, new floats.

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if someone can give me an idea of what to check or change i'd be very grateful.

I'm about as sure its a fuel problem as i can be. I have checked spark, have spark. Timing was set in the spring, hasn't been touched. New battery, new coils, new spark wires, new plugs, new spark caps, new floats.

Float heights?

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I had thought that, since i did replace them recently, however i set them to stock via the workshop manual. I will probably pull them and check them against the old floats to see if there is a difference in heights.

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is it maybe pulling air from a split carb rubber?

when you say it pulls the fuel when you cover the carb with your hand it may be pulling too much air.

it will pull air easier than fuel. ;)

also take of the tap at the tank and make sure it is clear, there should/may be a filter in there.

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Float heights?

Turns out you were the winner.

I had the floats wrong. I thought they were set right, guess i was wrong. I had them too high, set them too low, and they started overflowing, set them again, and its running now. It needs some fine tuning, idle isn't perfect, seems to fluctuate when it wants to idle. It also pops a lot when you let off from mid to high RPM.

so it needs some tuning, but the fact is its running, and that is more than i could say yesterday.

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As Shed hermit suggests, check the inlet rubbers for splits & tightness to the head & also check the carb diapraghms for splts or even the smallest of holes.

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I have been all over the diaphragms, they are excellent. The idle is weird, it isn't constant, sometimes it wants to die, others it idles at 2k. I think this is because they need to be synced, and the idle screw fine tuned however.

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Turns out you were the winner.

even a blind squirrel finds a nut sometimes :)

have you checked the petcocks? my 500 does the same thing if the petcocks are gunked up.

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even a blind squirrel finds a nut sometimes :)

have you checked the petcocks? my 500 does the same thing if the petcocks are gunked up.

I have not, should though. However before the one clear line i have would be about half full all the time. Now it is completely full all the time. I'll check the petcocks once i run through most of this tank of gas.

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