Check out Luna Cycle, they'll have kits to do exactly what you are looking for. Its quite straight forward and only requires 2 or 3 basic bike tools to complete.
I like the Como 2, but its about 3 times the cost of a Roll Sport plus a BBSO2/HD kit.. One thing I would recommend is but the lower...
Nice looking bike! I originally wanted to electrify a Roll Sport, but I couldn't find any good deals on them. Ended up BBS02ing My 8 year old Trek Pure Sport and a new Raleigh Venture 4.0
http://www.vilanobikes.com/vilano-core-electric-belt-drive-single-speed-commuter-bike-700c.html
Its incredibly inexpensive at $799 and belt driven what?!. No idea what branded parts they are using. I see "sun moon" stamped nearly the belt drive hub motor. May make a good review bike!
I'm...