"Ahh Dave....about that spark plug hole....well, we tried to put the insert in but....the threads were so messed up it wouldn't hold. So we went a size larger and....well it seems that head is like soft pudding - I guess it musta got overheated sometime; so much that it won't hold a thread, basically its buggered pal. Hey, stop crying. Would you like to buy one of these-here plastic-demon cookie-cutter road bikes instead? We could part out your 750 and make you....100 bucks or so."