Well If it hasn't been ridden in 20 years then I will only give you $10 to sell it to me JK. Get some good carb cleaner, they sell buckets of it that you can soak the carb parts in, I found that works really well. I would test the electricals before you really do much of anything. Take the spark plug out, put it in the boot and hold it by the boot so the threads are touching the outside of the cylinder. Watch the spark contact and crank the pedals, see if it sparks. If it does thats good news, if not may have a loose connection somewhere or thyristor unit may be shot (jawas are notorious for this) If it is shot, it may take a little while to find another, not sure where you could find them other than here or watching ebay. Anyways, good find on the supreme, wish I could find a top tank in this town.