First off, this is on an '87 Elite 50s scooter, which is really a scooter, but legally a moped. I don't know how many "mopeds" this might apply to...
Researching any mods that might apply to my bike, I found that there might be a restrictor on one of the pulleys for the belt that drives the back wheel. I wasn't exactly sure how it was supposed to work, but I decided to look for it today, on my lunch break.
I didn't find the restrictor, but I did get a good look at how the pulleys work to give the bike a variable speed transmission. It makes sense, and it's very simple. Not much to go wrong, there.
I had the belt off while studying it, and I think I may have put it back on backwards from where it had been worn in. I noticed on my way home that the bike didn't take off as fast as usual, but I was hitting 40 going downhill. Up till now, I was only hitting 36. I figure putting the belt on backwards, the belt is worn at different angles on the two sides, it must be riding higher on the front pulley, somehow.
The belt looked pretty worn, I think I'll replace it tomorrow (couldn't do it today, the cycle shop is closed on Mondays). I'm interested to see how it affects the bike's speed...
Do any traditional mopeds use this type of transmission?