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Trying to get my 74' CB450 sorted out. 2 things I discovered.

!. There was fuel underneath the bike when sitting in it's center stand and parked overnight. So I'm assuming that the float levels needs to be checked and adjusted. Is there a procedure for it or have you Guys used the "clear tube" method ?

2. Under closer inspection, I removed the 2 fuel lines when the Petcock after turned off but fuel still drips from the 2 fuel tubes. So I'm assuming that maybe that was causing the float bowls to fill too full and causing fuel to spill over into the drain tubes running from the bowls to the ground ?

So, If I need to rebuilt the Fuel Petcock and I'm assuming I do, What rebuild kits are you Guys using ?
 

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Sounds like two problems. First, the petcock seal needs replacing. Second, even though that problem is present, the carbs still shouldn't leak.

For the petcock, I got a random kit on eBay several years ago; so far, so good.

For the carb leak(s), have you determined if it is one or both? And, is it from the overflow tube, or bowl drain? My drains don't have a tube, so the clear tube isn't an option for me. To check the levels, I use a bit of sheet stainless that I cut to the shape shown in the manual, hold a float up with it, open the petcock, and see if fuel flows more than enough to just wet the valve; I adjust accordingly. You may also want to take the floats off and give them a shake; if one is leaking, you will hear the fuel slosh. One thing about the overflow tubes - they can crack, and behave as though the floats aren't working. The cracks can be really hard to see, but if you dry the bowl, place it carefully over a paper towel or dry rag, then carefully fill it, a crack will show up as a slow leak.
 

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Even when new our float valves are at best marginally effective at stopping fuel flow completely for long periods. The overflow from the carbs can sometimes gets past the carbs and intakes and into the crankcase. If there is any hint of fuel smell from the oil it needs to be changed before running the engine.
 

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Even when new our float valves are at best marginally effective at stopping fuel flow completely for long periods. The overflow from the carbs can sometimes gets past the carbs and intakes and into the crankcase. If there is any hint of fuel smell from the oil it needs to be changed before running the engine.
I meant to mention fuel in the oil, but forgot; it is a real concern. I had a float sink while riding, and started spraying fuel/oil mix on the rear tire through the crankcase vent; luckily I was only about a mile from home, but that ride was interesting.

As far as the float valves go, I was lucky enough to find 'rubber' tipped ones that fit and work perfectly, so mine don't slowly drip fuel when closed. The older the metal tipped ones get, the more they deform, and leak.
 
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