Hi, did you disable the decompressor when doing the compression test.
Yeah, the KACR could be messing up the compression readings. But I'm thinking something is amiss when it does so poorly on the leakdown test. Unless somehow the KACR packed up and is holding the exhaust valve open? I have no idea, just throwing it out there...
Hopefully it's not too big of a fix, I remember on David's bike he did the 685 while he was fixing it as it was oil burning anyway. Can't remember where he got his rebuilt head from though... Wymann maybe? Bah, my memory sucks!