Hi Walter,
The car looks great in it's new paint!

Harvey has been asking me to re-paint his S2 blue! I wish he'd make his mind up, he chose Red, I wanted Blue in the first place, Bl**dy kids!

As for the sprocket problem, the Cycle 'Cassettes' from the rear wheel have a good number of possibilities, You might find one with 12 teeth, the two I used had 14 as the smallest, but ask at your local cycle shop, they should be able to help.
The beauty of the Invalid Scooter is the 'Rose Joints' on the front steering (you did get one with 'Rose Joints?), this makes adjusting it a doddle. Check out my website Walter for a few ideas!

The other advantages of the scooter are all the realistic features they have lights, indicators etc.
Glad to see your making progress,
Keep busy,
Regards, Mark.
PS,
I've just come in from the shed Walter, and have noticed a flaw in my idea. The small sprocket from the cycle cassette is threaded onto the hub bit, and is the one that holds all the others in place. The thread is very fine and there is not a lot of excess metal on the edge to allow it to be bolted to the scooter hub like I did. Unless you can cut threads that fine onto the scooter hub, or make some sort of adaptor, I don't see how you can do it.
The only thing that I can think of, is to use a larger one at the motor end (18 or 22 teeth) the same as I did, and find a way to replace the 18 tooth sprocket which comes with the wheel assembly for a larger one (26 / 28 teeth). I have never seen one of Richard's wheel assemblies, so I am only guessing, can the cog be removed easily, or would it be a big job? Could you possibly bolt the larger sprocket to the smaller one, or would it cause alignment problems?
Hope this helps Walter,
Regards,
Mark.