Just whipped the rocker cover off and it appears everything is still there (phew). But the decompression shaft did side out as I took the cover off (possibly because the bike is on its side-stand. Would that be normal? I also notice the cam chain is SUPER tight, eg you can barely move it all. Is that how it should be? EDIT: just re-assembled it and tried to start with out the spark plug in (easy decompression check) and it ticks over ok now.