Glad it's fixed. It sounds like the bike needs some kind of chain adjusters like my old motorbikes used to have. These consisted of a washer welded to a thin threaded bolt that was tightened onto a sort of folded channel on the end of the forks. You can see from these photos how it would work They hold the axel against the pull of the chain, an special problem with a motorised system that can pull damned hard.:




These ones are available on Amazon.com

http://www.amazon.com/s/ref=nb_ss_gw...juster&x=0&y=0