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Discussion Starter · #1 ·
so its a 4 stroke, i have new boot mounts, new pods, and my carbs have been cleaned top & bottom with the all 4 floats checking out. but im still losing lots of gas out the overflow and some out the air pod slots on both left side carbs, right side runs no problem. what do i do next?
 

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"all 4 floats checking out" - what do you mean? Did you verify the levels were set properly? That the float needles do not have wear rings on the valve ends?
 

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Until you find the proper levels, you can check to see if the ones that over fill are different from those that don't; assuming there is no significant wear on the seating surfaces, that is.
 

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Discussion Starter · #6 ·
may have found the problem, i unplugged the vacuum hose from under the gas tank and fired up the engine. the overflow problem stopped, so i turned it off plugged it back in. fired up the engine again and it immediately went back to overflowing. unplugged it again and the leaking again stopped. so it seems that the petcock is the problem. ill replace it and post the results here hopefully this week.
 

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The petcock just lets the fuel flow to the carbs when vacuum is applied to it, it doesn't control the fuel levels in the carbs; that is up to the floats and float valves. If the levels are set correctly, and the floats actually float and shut the valves, the petcock could be bypassed and the carbs still would not overflow. So, it comes down to, the float valves are not shutting off. The question is, why? There could still be a bit of grit in the valve seats, or the floats could be sinking instead of floating. The only way the petcock could be at fault is if the vacuum diaphragm is leaking fuel into the vacuum port, which would usually show up as fuel in the cylinder and oil, not leaking out the carb overflow.
 

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Discussion Starter · #8 ·
When I took appartment the carbs, the inside was actually increadibly clean. Except for one bowl (minor build up and yellowing) it only really needed a little carb cleaner and a wipe down. What I have read up on with the petcock it that it can cause gas starvation or overflow if it is bad. I happen to have a spare petcock from a parts bike, I'll try that first. If I still have issues then I'll tear down and check the floats again.
 

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The petcock just lets the fuel flow to the carbs when vacuum is applied to it, it doesn't control the fuel levels in the carbs; that is up to the floats and float valves .
^ True that ^

When I took appartment the carbs, the inside was actually increadibly clean. Except for one bowl (minor build up and yellowing) it only really needed a little carb cleaner and a wipe down. What I have read up on with the petcock it that it can cause gas starvation or overflow if it is bad. I happen to have a spare petcock from a parts bike, I'll try that first. If I still have issues then I'll tear down and check the floats again.
If the floats are not sinking. (Filling with fuel if they are the hollow type).
Then something is wrong with the float valves.

Are you sure you got the float valves clean, clean, clean?
-OR-
Debris may be coming in from the fuel tank (or petcock) making the float valves leak.
-OR-
The seat of the float valve can get very minor pitting (HARD to see) and make them leak fuel.
-OR-
Assuming the float valve is replaceable. (Not 'cast in' the carb body).
The '0' ring around the outside of the valve seat may be deteriorated and letting fuel by.
 

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When I took appartment the carbs, the inside was actually increadibly clean. Except for one bowl (minor build up and yellowing) it only really needed a little carb cleaner and a wipe down. What I have read up on with the petcock it that it can cause gas starvation or overflow if it is bad. I happen to have a spare petcock from a parts bike, I'll try that first. If I still have issues then I'll tear down and check the floats again.
The petcock can cause fuel starvation, but can only cause overflow if the float valves are also bad. From your description of its function, the petcock works normally. Back to the float valves ...
 

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Discussion Starter · #14 ·
alright, resealed the tub and fired it up, no leaks what so ever.

now i need to figure out the RPM issue. its idling at 4k reps. adjusting the throttle bolt in either direction has so far not had any effect. it does smoke quite a bit and smells of burning oil, but that is believed to be from a) sitting to long without running and b) oil in the mufflers due to my added marvel magic directly under the spark plugs. now i did find last minute today that the throttle cable was slightly kinked up underneath the gas tank. loosened and made quick adjustments but wont results until this afternoon.
 
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