series 20 torque converter ?

[pearl111]

What purposes do you usually use a 20 series torque converter for? Would it be for easy driving go-kart at easy/slow speeds on pavement?
And maybe with a Pred. 212 with the governor still installed?
Reason being, I'm working on building an old school three wheeled chopper for my grandson.

Also, ...... I'd like to know why and when is it best to run a 20 series torque converter.
As you can tell I'm "clueless" about a 20 series TQ, when I look at them online it seems there is no backplate, and you have to buy the TC
in separate .... parts/components.
Thanks.

 

[pearl111]

Also the driven if I'm correct can be, ....6" or 7" dia. what is the difference?
Thanks.

 

[pearl111]

I learned a lot from JimD's post..... go kart wheels always turning.

 

[panchothedog]

The 30 should work just as well, more popular, easier to find, and probably cheaper. A 7" driven clutch will give you a lower gear ratio when initially starting out. Better acceleration and hill climbing ability. Same top speed as the 6".

 

[Denny]

The 30 series TAV II was designed as the mini bike replacement for the 20 series originally. The 20 series is more efficient.

 

[pearl111]

Would 20 series TC be the same as a 30 series, .... without a backplate?
Or could you use a 20 series TC with a back plate?

What I am wondering is how can I run a 20 series TQ without using a jackshaft, .... I'm guessing that's imposable.

 

[Denny]

A 20 series is a closer relative to a 40 series than a 30. The 30s are a different animal all together. No a 20 will not work with a back plate because there are no reverse wound springs available as far as I know and only the one direction ramp. Have to have a jackshaft, sorry.

 

[JimD]

Denny - Comet had both springs for the 20 series --same spring for the 20 and 30 series. I am sure Certified Parts carries both style springs still. The series 20 does require you to build your own jackshaft which is why the majority of people will go with the series 30 which normally comes only with the smaller driven because of space restraints. The series 30 wears belts quicker because it gets hotter than a series 20 because you are forcing the belt up the flat side of the fixed sheave.

When a series 20 is used, the driven should be mounted with the ramps facing INWARD (towards the engine). This way the driver and driven are moving in unison. The driver on the engine moves toward the engine and upward while the driven unit when mounted inboard moves down in to the sheaves and inward the same direction as the driver. We made them both ways which is why we mark on the driven INBOARD or OUTBOARD mount.

We did several style jackshaft the most popular on was the tube which BMI buys. The laser cut plate was our last design but karting was over just as we introduced this one so we only had made 50 when the lights went out for the fun kart manufacturers. The tube requires you to use 8 bolts when securing it to the motor mount plate. Don't be tempted to only use 4 and drill the holes all the way through because you will crush the tube when securing the engine. Yes, I know you can make spacers out of conduit but buy the 8 bolts.

 

[Snaker]

A 20 series is a closer relative to a 40 series than a 30. The 30s are a different animal all together. No a 20 will not work with a back plate because there are no reverse wound springs available as far as I know and only the one direction ramp. Have to have a jackshaft, sorry.

You bring up a important point about the single ramp helix.
That ramp direction dictates the spin direction of the pulley.
But I think? that I've seen various 20 series driven's with single direction ramps and dual direction ramps.
If so, I guess a dual ramp 20 would be similar to the 40?

Personally, I don't buy the notion of the symmetrical CVT's working well with the movable sheaves on the same side by "floating".
Only way to get away with that is with low powered engines but folks claim success.
A bigger powered engine would destroy the belt.