I say "mad" because I am apparently slightly mad for considering it, but also because I want to swap this engine into a Sachs MadAss. For those not familiar is a small street legal cycle with an interesting industrial design aesthetic powered by a Chinese clone of the venerable Honda CRF50 engine. To spare repeating myself, I recently started this thread in the Honda 2-Stroke forum: http://www.thumpertalk.com/forum/showthread.php?p=10391839 Okay, what I have in an engine from a 1980 CR80R pulled from a junkyard parts bike. I got it complete for $50. After taking the top end apart it seems the piston skirt shattered scoring the cylinder wall and generally banging up the combustion chamber. The connecting rod big-end bearing feels very sloppy and needs to be replaced. Before I put any money into this engine I need to know if I can afford to fix this. From reading around here it seems that standard operating procedure in such a case would be to replace the crankshaft. To my surprise they seem to be available from the Part Store of this very website, however for the extreme price of $430. That would just blow my budget right out of the water. Looking at the parts fiches, apparently the crank pin is a separate piece and is only $15. Why not simply replace the pin, bearings, seals, etc. and call it good? Forgive me if this is a stupid question, I'm new to the world of two-stroke engines. I've always wanted one but two-stroke street bikes are extremely rare now a days so I have set out to build one of my own. I'm very comfortable with a wrench though I lack the special pullers and such required. I know my way around 4-stroke engines but these 2-stroker seems to have a few tricks to them. Thanks for any help!