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1972 750 k2 Carb problem

TsabbK2

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Seattle, wa
Hey guys I have a '72 750 k2, I love it. Last year at the end of summer I noticed if i let the bike sit after riding, I would come out to a puddle of gas underneath her. I can't find a leak anywhere. I can ride all day and nothing... until She sits all night. The #4 carb is pretty corroded, I'm also trying to locate one of those. If you guys have any input it would be much appreciated! (so the wife quits yelling at me about the smell)....
 
The needle and seat are leaking by. Fuel is coming out the overflow tube that runs down between the engine and swingarm.
 
Digger is spot on with the source of the leak. I have the same year bike for some reason the plastic floats seemed to have gained a little weight over the years and I had to raise the the tangs on the floats a little higher than spec,s and it cured My problem. You still have to shut the petcock off during non use, Drove Me crazy until I did this procedure because I was going by the book spec,s. But as Dirtdigger pointed out check the needles and seats to make sure there stopping flow at full closure.
 
Because the needles are not rubber tipped a small speck of dirt can cause them to leak intermittently. You can put the rubber tip needles out of the keyhole carbs in the early carbs they are just a bit longer and you will have to bend the tabs a little on the floats. But this makes the carbs more resistent to the intermittent dripps. Also check the floats and make sure they still float and check all 4 side by side to see if they are all the same.
 
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