Strange lack of compression

[Miles]

Looking for any advice on this problem. After a nut and bolt rebuild of the bike I finally started it a few days ago. Barely started and massive issues with running.

After a compression test I found 60-80-90-80. All well below what it should be. I suspected valves as it was my first time lapping in.

Stripped the engine today, poured meth into the bowls, excepting it to just run straight through, 20mins later still had the meth in the bowls.

Head & cylinders were skimmed level.
Brand new head gasket
Timing 100%
Less than 200 miles on the rings
Bores honed
Bores measured and bizarrely found to not only be within the 57.012 limit but also not even 57.00, biggest was 56.7. Therefore would expect compression to be high.

Ran out of ideas now as I don't know what else would cause low compression

[zimm]

jump it off a car while doing the test, sometimes the starter just isnt up to it. ??

failing that, its the valve seats or the cam timing, or maybe the valve clearances if they're a bit on the tight side. ?

[CaNsA]

I might be chatting out my butt, beer inspired waffling, but...

If the leak isnt between pistons and cylinders, or a weeping HG, then it will be at the top.

Check the valves are seating properly.

[Miles]

Tried putting meth in the valve bowls to see if it went past the seats but an hour later it was still there so have to rule the valves out

Now looking at zimms idea of timing being out due having to skim a warped head and warped cylinders.

Fed up with it now, 3 summers of riding now missed now due to one thing or another and I'll be damned if I'll miss another one so the engine is off to Ivor Greenwood (top engine tuner over here) in the morning. He can dail in the cams while he's at it as well.

Thanks for the help guys, I'll get some pics up of the bike soon

[ozzyb_92@hotmail.com]

Any luck Miles I'm going through the same sort of jazz, I have very very low compression on 3&4 and I'm so confused?