Based on this thread, I bought a 250w electric motor and battery conversion kit from Leonard at Relectro. I have been using the system for a week now, and it is just great. Leonard was extremely helpful in answering all my questions, and I had my new motor, battery and torque arm installed on my racing bike in a matter of days (Dunkeld Cycles did the conversion). I am now able to get up the hill to Rosebank in the mornings without breaking a sweat, and use my car even less now. Thanks edkin and johanhorak!