Originally Posted by VENICE BOY
I would say, If you haven't purchased the bike yet... You should look at buying a different model Schwinn!
You will save money & have a much easier build! (the 5-speed wheels with 5 sprockets on them work very well!)
The only Schwinn with springer forks in Australia is the D7. I'm sick of the bumps from the rigid forks on the Alloy Seven cruiser and it gives the Grubee motor mounts (not a good design - steel threads into aluminium) a terrible hammering. It also comes with front V-brakes cos a coaster hub alone is totally inadequate for stopping a motored bike and the caliper brakes often used with springers are a very bad brake design associated with cheap bikes. These qualities make it almost perfect for motorising and the only problem to overcome is the big Shimano 7-spd hub which accounts for about 50% of the bike's $820 price tag. I don't want to chuck the hub out and install derailleurs but I would if there were V-brake bosses on the seat stays but there aren't.
The answer lies in trying to build a 50T sprocket that will fit over a Nexus 7 hub and that is quite easy but then you need new clamping plates and asbestos rubber cut to a different radius to clamp the sprocket onto the spokes. I've thought a lot about this and I think the only good option is to design a totally new sprocket with new fittings that can be used on this model repeatedly and then keep building the same model of bike.