General air leak question

Sloppyslopster

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Hey. Just want to ask what you guys do to properly detect air leaks. Like where on the engine should I look and what fluid one should use to spray. I tried using wd-40 but I’m not too sure how good that is.

Pretty sure I (still) have a leak. Bike will die down to low rpm at idle and when I blip the throttle it revs real high up. Also has a hard time keeping idle and tuning is a nightmare.

Thanks for any help!
 
Hey. Just want to ask what you guys do to properly detect air leaks. Like where on the engine should I look and what fluid one should use to spray. I tried using wd-40 but I’m not too sure how good that is.

Pretty sure I (still) have a leak. Bike will die down to low rpm at idle and when I blip the throttle it revs real high up. Also has a hard time keeping idle and tuning is a nightmare.

Thanks for any help!
Carb cleaner is probably the best bet, but brake cleaner also works (in a pinch)
Most common place to leak is between the intake throat and carb, but the bearings can leak too, as well as the case.
 
Base gaskets, case gaskets, head gaskets, manifold gaskets, and the carb connection on the manifoldis where most air leaks are. Carb clean or brake clean is my go to.
 
The very best for checking for leaks is a little mist of water. It's not volatile and burn your place down. The engine will just die and the water will evaporate quickly on a warm engine. Another place for an air leak is the spark plug, but that is more of a compression issue. High idle is an air leak usually from the carb to intake or intake to cylinder, also check the cable connection at the top of the carb.
 
I suggest not using carb and brake cleaner around rubber seals as it causes the rubber to swell and can mask the problem. A mist of water as Chainlube suggested works just fine, and it has the added benefit of helping cool your air cooled 2 stroke as it sits still running ;)
Sounds good! Thanks guys. I'll have a look tomorrow and see what's up. I'm assuming its something minor tbh. I think seals are fine, I tried my best to bullet proof the life out of them even to the point where I bought viton crank seals and upon installation I put a light-ish coat of gasket maker on the outer bit of them so they REALLY seal up good.
 
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