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i recently cleaned out my carbs and did some other stuff while i was at it.
im in the middle of some other sthings so its not totally reassembled. i have the fuel overflow tubes off.
while i had it running i noticed a lot of fuel coming out of the overflow. how much is normal. i want to make this as efficient as possible.

do i need to do a float adjustment?
can i close them off compleaty
would a return system work on my model?

Sounds like your floats are not set correctly.

I agree. You shouldn't have any fuel coming out of the overflow tubes. I think JohnJ is correct. You probably set your floats too high when reassembling the carbs.

You set the floats too LOW.
High shuts fuel off early.
Make sure the tang on float is contacting shut off valve
PJ

If float adj. don't work check the needle and seat.

crazypj wrote:You set the floats too LOW.
High shuts fuel off early.

Maybe it's just a semantic issue, but when I set floats to low, a small amount of gas enters the bowls, causing the floats to rise and shut off the fuel prematurely. When I set floats too high, an excessive amount of gas enters the floatbowls (and goes out through the overflow) before the float shuts off the supply.

Either way, fuel coming out of the overflow is a sign that all is not right with the float or the needle.

I had this problem with both my 72cb350 and 71 cb450 twins.

The soldered brass floats leaked at the soldered joints, and sank. Hole was in the bottom of one, so it only sank a bit.

It was one thing my old man taught me- soldering floats up.

But it sounds like your bike has been apart for a bit- I'd go with setting the float height as per the workshop manual instructions. You HAVE got a manual, don't you?

Let us know waht happens