Leakdown and compression

[davesax36]

Is it possible to do a leak down test that shows less than 4% loss, and still have top end issues?

My leak tester is reading 88 psi in and 86 psi out on all cylinders. Cylinder 3 plug looks rich, but not soaked, and I'm getting 20mpg. I'm very concerned about gas washing that cylinder and am wondering if redoing the compression test with a couple drops of oil in the cylinders is worth it due to my leak test results.

At the end of a ride I'll usually have a wet carb body #3 between the air box and v-boost rubber. A friend of mine is saying it sounds like a clogged air bleed somewhere that's loading at cruising rpm, but doesn't act weird at idle. I want to get this figured out and run a couple more tanks through it before the motor comes out. It's already been pushed back too far.

Thanks, guys.

Sent from my Galaxy Nexus using Tapatalk 2

 

[MaxMidnight]

A compression or cylinder leakage test will help identify any issues with piston ring or valve seat sealing.
It won't help with incorrect fuelling.

I would start by checking that the air filter is clean.
Then check float heights.
If they are OK strip, clean and inspect the float needles.

 

[Fire-medic]

The leakdown tells you your top end is healthy, or not. Fueling should be better than 22 mpg in a stock engine. W/stage 7 & a 4/1, my bike doesn't do much better than that in stop & go traffic, but I got 34 mpg highway in Daytona, last time I checked.

Your stock settings for the carbs should be checked as was mentioned. Yes a poorly-sealing needle valve & too-high float setting will cost you mileage.