[Overdriven]

I know you probably can't move the sprocket to the other side of the wheel, but can you flip the wheel so the sproket is on the correct side. IMO if you're going to be fabbing brackets, fabbing a new brake bracket on the other side would be a simpler/cleaner setup. That's assming you can get your gearing without a jackshaft. A jackshaft also complicates chain tensioning, since you now have 2 to worry about. And your more likely to run out of motor/axle adjustment and be in between links on the chain (too short, adding 1=too long), so do mockup with complete chains in place. Ebay used to have alot of sprockets when pocket bikes were popular.