started pulling my US ebay 360 engine apart today.Looked a bit untidy on the outside,someone had butchered a nice ACK manifold with 4 grub screws to hold on a carbi,countershaft sprocket welded on,barnyard screws holding all the covers in place,leaking a bit of oil through the countershaft seal.Head off,not too bad no carbon buildup,barrel off,piston out,measure up wow standard bore and piston according to CZ madness site.Undeside of piston scorched 450 main jet in the carbi I think means methanol.Hand cut gaskets under the barrel and the gear inspection plate of articles from a magazine from Houston Texas all working fine.big end tight with no play.Things are looking up.Can anyone who has a sidepipe manual tell me the recommended piston to bore clearance,will get the bore cleaned up and new piston.Off to work on that sprocket ???cheers