Hey Dan, looks like your a bare bones Debbie downer... Bet you got herpes...Looks like a bare bones build with the 3:1 tc. Bet you burn out your clutch in less than a month and have full transfer case failure in 2 months. You will want around 17:1 reduction on flat ground or 20:1 reduction with hills if single speed. Your reduction is too low, bet you cook your clutch at any speeds below 20 mph.
I have the 44 tooth sprocket, I will look into getting a bigger one, I really appreciate the way you worded that.Grats on your build! Treat it right and it'll cruise a long time!
Some people have had bad luck with that transmission, some have made it work for years. Key thing is to not run too tall of a ratio. You may have to replace the rear sprocket with a larger one to get an ideal gear ratio. If the output sprocket on the transmission is 10T, you'd be better off with a 56T rear sprocket. You appear to have a 48T rear, but I could be wrong.
Def going to pick up a belt drive, I'm wondering where to find the bigger sprockets, I've found the standard ones but they were kinda expensive, I can't imagine the price on a 100 tooth sprocket...That is a great motor, just keep on eye on the trans. The inner chain stretches just like the drive chain and it is not known for its quietness, performance, or reliability.
On the bright side, swapping it to the 7g belt drive setup is a pretty simple swap and is MANY times better so you have that option once it starts giving you issues. They make a 100t that will get you ~27-30mph on stock setup and a harder to find 80t version that does around 34mph and both will be smooth as glass and last many miles.
The HS 49cc will last as long as 3-5 chinagirl rebuilds, around 10k with good maintenance.