Gearing with TC questions

#1
On the mini bike I'm running a TC with 19" tires and a ration of 7:2 and it rides good, take off is ok but takes awhile before I hit 40mph. From what Iv read the TC needs to be able to go into overdrive so a 72t worked for that in the rear. It's a cruiser so I'm happy with that.

This trike will have 16.5 x 6.5-8 tires, a TC with either a 10t or 12t jackshaft sprocket
And I'm trying to decide on the rear sprocket size.

I'm using a 212cc engine so a 30 series TC is what I'll use. I'll be using it on grass and street so what ratio would you guys recommend ?

I want something that takes off good and hits 40 or higher on the street, but I don't know if I'll get that with this setup.
 
#2
IF you calculate the engine Max RPM, Front/Rear Sprocket size, and then tire size, you can get your max potential speed. Most of the torque converters give you a close to 1:1 final ratio. 40 mph out of 6hp with good take off speed might be a stretch. Roughly looking, I would think you would need around a 37 tooth rear on a 10 tooth front to get a potential 40mph.
 
#3
I'm hitting 40mph with a 72t rear, takes a little while to get there but it cruises. Iv done all calculators but that doesn't take the TC into play.
I'll start with 6:1 and go from there.
 
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