[Aussiecrf230]

We do get robbed in Oz for bike tools.
I made the last one out of old plug and an air fitting.
The 10mm plug means you would need an adapter as too small to tap out for fitting.

Letting the Pros have a go might save you some riding time too.

[chaddles101]

Took the head off and brought it to a machine shop down the street.

It holds a vacuum perfectly on both intake and exhaust. The concern is, in under 2 hours of running the exhaust port was full of carbon

They said I should next look at the cylinder bore, and/or the piston rings because there is a hell of a lot of blow by

[JimDirt]

A lot of times a Compression Gauge setup will assemble the same as a Leak Down Tester , so you can sometimes swap parts around
, when you look for a Leak Down Tester , look for one that resembles the fittings on your Compression Tester .... most Compression Testers have a hose/fitting for motorcycle/metric spark plugs , so you can use that hose (at worst have to make up a set of connector adaptors to attach the 2 hoses together) and then you are good to go .....

On a side note , I have a Snap-On Leak Down Tester , and it came will all the spark plug adapters for pretty much any spark plug thread ..... but my Compression Tester also has pretty much every spark plug adapter/fitting there is available , as well .......