Re: Narrow sprocket and chain- Not recommended here
There's no doubt the motor will pull with a 41 tooth sprocket, that's lowering the gear ration a bit so there's more torque available at the wheel. I had a bit of chain stay clearance problem on my bike, the cure was to flatten the chain stay tube on the inside to give the chain more room. I welded a piece of steel on the outside of the crushed area to reinforce the tube but in aftersight it really didn't need to be reinforced. The good thing was I was able to do away with the idler pulley. So far I've put about 40 miles on the bike with no problem. Mileage will build up a bit slowly because there are two other bikes in the garage that need riding too.
Goldwing 1500, Silverwing 600, Schwinn 49