TAV2 Torque Converter dimensions

[Timbone]

I am well into my 4 stroke B &S project, and I am thinking ahead to my motormounts. I will have to wait until my next paycheck to order the unit, and I need to know how far left to shift my 140 cc motor.

The driven unit of the TAV2 has a support structure that kicks to the motor side of the unit. Since I am going to align a swingarm axle with that driven unit, I need a very good idea of how far inward that kicks. It also determines my chainline for the motor drive.

I hope my question is clear. Does anyone know the dimension of the inward kick of the driven unit?

 

[Frankenstein]

I am well into my 4 stroke B &S project, and I am thinking ahead to my motormounts. I will have to wait until my next paycheck to order the unit, and I need to know how far left to shift my 140 cc motor.

The driven unit of the TAV2 has a support structure that kicks to the motor side of the unit. Since I am going to align a swingarm axle with that driven unit, I need a very good idea of how far inward that kicks. It also determines my chainline for the motor drive.

I hope my question is clear. Does anyone know the dimension of the inward kick of the driven unit?

I understand the question but since I don't own one I couldn't tell you, here is a photo from the company of their tav unit, the right side is the plate mounted directly to the engine face, the left under the the driven pulley is the (presumably) 35 sprocket.

An estimate by eye would be about 3/4in outboard the face of the motor itself.

 

[Timbone]

Your guess on chainline is good. My rear forks have about 7” clearance so chainline will not be a problem.

I am using BIG tubing, about 1 7/8”. My real concern is that support structure for the axle on the driven sprocket. I need to keep that out of my drop loop and out of my supports for the rear swingarm. Looking at my motormounts hook ups I have a narrow left to right shift, unless I am forced to get super creative.

 

[curtisfox]

TAV2 any better then comet? .......Curt

 

[Frankenstein]

TAV2 any better then comet? .......Curt

Comet is the company who produces the torq a verter, and the successor to.

 

[Timbone]

I’ve been doing math gearing, reading up on the TAV2. At low RPM, the torque converter is running something close to a 3:1 reduction. At highest RPM is 1:1 or maybe slightly better.

I’m thinking 48 to 60 is a reasonable range for a rear sprocket. Not sure what the reduction is at 3600. Assuming 2:1 reduction at 3600 RPM, a 48 sprocket will turn a 24” wheel at about 27mph. Very nice if accurate!

My math for turning 5000 RPM at 1:1 final drive reduction yields very high numbers!

 

[curtisfox]

Comet is the company who produces the torq a verter, and the successor to.

Had that in my head, just never heard of the tva2 before, what would be Kool is if they made a small one 1-4 hp. Have 2 pocket bike ones that have cracked threads on the shaft, makes the clutch bell warble. ........Curt

 

[Timbone]

The catch is that you have to cede a bit of power to gain mechanical advantage of a torque converter. So these won’t be useful in low HP scenarios.

 

[curtisfox]

The catch is that you have to cede a bit of power to gain mechanical advantage of a torque converter. So these won’t be useful in low HP scenarios.

Yep I know, but still think one could be made for small power, that wouldn’t take so much power..........Curt