Re: Do I need a special chain for my mb?
Just noticed the OP asked this question on 6/22/12 and has not replied to this thread. Just in case he forgot:
Why did you not use the chain that came with your engine kit? Typically they come with a #415 chain that if installed and maintained correctly should suffice.
As was said above, a good alternative is the #41 but you won't find it at a bicycle shop. Ace Hardware carries it as well as Grainger, Tractor Supply, and other industrial suppliers.
Tom