‘07 KTM 525 EXC - cylinder leak down test. Method and results.

The front wheel is up high to keep the engine oil from draining out the crankshaft locking bolt-hole. Thanks to Paul Oleson at DIYMotoFix.com for his guidance in the book: “Four Stroke Dirt Bike Engine Rebuilding Handbook”. I bought the same gauge set that he used. OTC 5609, from NAPA. CAN$ 114.00 + tax.

[@zepto9]

Correction: the second time I mention the flow-restricting orifice between the two gauges I say “one inch in diameter”. The correct value is “one millimetre diametre”. That’s what I believe the orifice size to be - the standard for doing aircraft cylinder leak-down testing.

[@dbm123car]

That’s good news.
I’m not sure of the 94% business ... is that 94% of what goes in the cylinder, stays in? Ie 6% leakage? Over what time?

[@japfourme381]

Correct.