Torque converter question

#1
I'd like to install a torque converter, but I may not have the room. Any body know the dimensions - particularly the shaft to sprocket - of the Comet TAV2 3/4" Drive? Looks like I only have ~ 7" - 8 1/2" to play with. Might just have to do a jack-shaft. Any input would be appreciated.

Thanks, JB
 
#2
I'd like to install a torque converter, but I may not have the room. Any body know the dimensions - particularly the shaft to sprocket - of the Comet TAV2 3/4" Drive? Looks like I only have ~ 7" - 8 1/2" to play with. Might just have to do a jack-shaft. Any input would be appreciated.

Thanks, JB
gokartsupply has in the comet 30 series section a list of belts and parts combinations listed with the c to c of the clutch components.
http://www.gokartsupply.com/tcbelts.htm
And ya that's tight...

This is a 7 inch secondary on a center to center ( I use the 91 belt yerfdog )
 
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#3
You could cut a plate a little different and move that engine forward.
Infact I would do things completely different and build an angle mount tilting the engine forward.

Not a critique of your work however.
What you have looks pretty solid and good.
 
#4
TAV will not fit with the swingarm brackets, if that is what those are just behind the engine.

Looks like a predator, if so, measure from the top left crankcase cover bolt 13" back. That would be the rear edge of the TAV30 backplate.

Don't think it gonna fit without a frame stretch.

Probably better to just go jackshaft.

Or if you do a TAV, it will not use the backplate, Like NOS above...
 
#5
Sure it can fit.

Use the Yerfdog jack shaft or something like it and tilt the assembly forward.


he already knows he has an issue by the use of rubber gummy buffers so may as well make a better mount.
 
#7
What if I slide the engine all the way to the left, so the case is flush with the edge of the frame? The torque converter would then not be encumbered by the confines of the frame. Then I would just need a short shaft mounted to a bracket on the frame, and could complete the run with a small sprocket, on the other side of the bracket (on the inside of the frame), to the rear wheel sprocket... if that makes sense :shrug: ?
 
#9
Sure it can fit.

Use the Yerfdog jack shaft or something like it and tilt the assembly forward.


he already knows he has an issue by the use of rubber gummy buffers so may as well make a better mount.
So does the engine sit on top of the Yerfdog plate or something? That would make things easy.

Still not sure what I'm missing here :confused: - are you saying the torque converter would hit the bottom tubing of my frame (even with the engine slid all the way to the left, so the entire crank shaft sits outside the frame) unless I tilted the engine forward? Sorry if I sound dense, trying to wrap my little walnut brain around this obstacle.
 
#10
After the last pic, you have some work ahead of you. Looks like a TAV would be outside the frame anyway.
Right. I know I'll have to have a bracket with a shaft welded to the frame - with the drive pulley on the outside, and the sprocket on the inside. . . unless there's something else I'm missing :confused: which is very possible. . .
 
#11
So does the engine sit on top of the Yerfdog plate or something? That would make things easy.

Still not sure what I'm missing here :confused: - are you saying the torque converter would hit the bottom tubing of my frame (even with the engine slid all the way to the left, so the entire crank shaft sits outside the frame) unless I tilted the engine forward? Sorry if I sound dense, trying to wrap my little walnut brain around this obstacle.
See how I am tipped up at the back and moved forward.
This might work for you.



Not so easy to see from this angle but the bottom of my 7 inch is above the base of the frame rail.

 
#12
Thanks for all the input guys. Rather than guess and buy parts I may not be able to use, I sent an email with pics to "Chet" at Gokart Supply. May just end up getting a standard clutch with a straight shot to the rear wheel - at least I know this will "work". But I really would love a torque converter!
 
#13
After talking with the folks at Gocart Supply, I ordered up all the pieces to make a TAV - minus the back plate and cover. I also made a paper template of a jack shaft hanger with room for the swing arm mounts, and picked up some 1/4" metal stock. Once I receive the torque converter, I'll make sure it all looks like it will fit, then it's off to the welder! Thanks again Newoldstock & Stangrcr1 for the guidance.
 
#14
My only concern is the slight change in geometry with the alteration of the swing arm mounts. I've created a bit more of an angle with the rear shocks, and increased the wheel base by about 2".
 
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#16
After thinking about it, I would rework the whole setup. But before I say more, can you take a pic from directly behind the swingarm looking toward the engine where the chain would run? Need the pic to show the sprocket looking forward. And then flip the rear tire and take another pic on the other side.

I just relooked at your first set of pics on the 11th and you have the right idea, just wanted to make sure from the rear.
 
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#17
Get rid of the gummy buffers under that engine.
Your not likin' my "gummy buffers" eh :laugh:
Actually, those are very hard rubber automotive engine mounts. My plan was to have a big fender washer on either side of them. Without elevating the engine, there would be almost no clearance between the cylinder head and the swing arm.
 
#18
After thinking about it, I would rework the whole setup. But before I say more, can you take a pic from directly behind the swingarm looking toward the engine where the chain would run? Need the pic to show the sprocket looking forward. And then flip the rear tire and take another pic on the other side.

I just relooked at your first set of pics on the 11th and you have the right idea, just wanted to make sure from the rear.
Here's what it looks like. The yardstick illustrates where the chain will ride.
I see what your saying about flipping the tire - to put the sprocket on the other side (right side) of the bike. That would work too. I'd just have to cut off the tab for the drum brake, and switch it to the left side.
 
#20
The last pic is the one I was looking for! You have the right idea with the cardboard template. Make the new plates and weld them in where the current plates are. Run the jackshaft with the driven outboard, and the sprocket just inside the bracket. Make sure you run the jackshaft to both plates as one bearing will not support it.

Make sure there is enough room between the jackshaft and the swingarm pivot for the sprocket to fit.

No flipping the rear tire.

The only other thing I would say is to put the swingarm pivot point in line with the jackshaft and the midway point of the swingarm's travel. A little above where you have it on the cardboard template.

And you can always cut an inch or two out of the swingarm's length, if it bothers you. I would cut it just behind the pivots, and take an inch or two there. Just make sure that when the swingarm travels up, the bends don't hit the frame.
 
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