Tav2 gear ratio...top speed

Ok so i have a drag mini bike...15hp with a tav2 12t. After install i know i need stiffer springs all around. I still have stock doodlebug rear sprocket (70t). To get more top speed would i go up in rear sprocket size or down?
I plan on running bike in the 1/8
and before i installed tav2 i had 15t max torque and i topped out at 52mph in 1/8 and im trying to get that with the tav but with way better takeoff.( im 215lbs)

and before you say "tav2 are no good for drag"... I have seen it done and it works.


Active Member
If you are looking for more top end speed just change from your tav2 12t to 15t. If you want a better low end go from the tav2 12t to 10t.
and before you say "tav2 are no good for drag"... I have seen it done and it works.
also seen some rubber that wore off the belt and stuck to the drive and driven pulleys. is that something to take a look at?
the TAV might work but you will probably start eating belts from the power.
LMAO! There is a reason Comet limits RPM on it's belt systems.

"Cheap mini bike TAV's SUCK for drag racing applications." But then anyone can call their bike a drag bike too.

Go ahead Dave, tell him at what RPM the belt starts sticking in the driven. :laugh:


Active Member
Sell the tav or use it on another mini. Get a disc kart clutch you need more hp at least 25 for a real MDB. Are you running a small block or big block? the dudes in my state are running 80 mph+ at the 660. Post a picture an some more info about your MDB.
At what rpm are crossing the line? We were doing 60 in the 1/8 with about the same hp but my son is 100lbs lighter. If you re-gear you trade low for top or vice versa.