Just an idea for tc

[Will]

So I was thinking about torque converters
I had an idea of a tc (with a jack shaft built into it) and instead of it driving a sprocket onto your axle, it attaching onto ANOTHER torque conveter, but instead, the spring that engages it is changed so it is constantly engaged, the second tc would drive the chain to the axle.
So two tc's, first drives the second (which is always engaged) and the second tc drives the sprocket which is attached to the axle.
I understand how there is a 10% overdrive so that would become a 20% overdrive.
I understand tc are expensive but buying 2 cheaper clone ones and testing it out might be a cool idea,
I thought that tc gives u a wider range than a fixed gear
So two torque converters would give a even wider range for the engine (by range I mean like how the ratio changes)
Let me know what you guys think ?
Cheers

 

[fowler]

yea it would work great in practice

but u must take into account u may not gain any speed doing it
theres a set ratio that is the max that engine can push that kart
u can just lower your starting speed to get more off the line

but u would have to tune the tcs as when to start shifting

otherwise u will just end up with a really low start gear
then a jumble of middle ratios and the same top speed
each tc will confuse the other with the changing rpm and torque and the load fed back

iv wondered what would happen if u put an accutal tc and an auto trans on a kart
obvously it would have to be a bigger engine like a 13hp
but somthing like a barg warner 35 is a nice light trnas

 

[Will]

Yeah, because if i was using a larger engine (13hp) the double tc might be very beneficial, I could tune the ratio so that it gives me maximum torque at the low end side,
Yeah I understand that no matter how advanced the gearing is, there is a limit,
But I will most likely be using a 1:5 ratio on 30 cm tires powered by a 13 hp, and the reduction ratio the two torque converters create on take off will help allot.
Cheers for the reply fowler

 

[itsid]

10% * 10% is 11%, not 20% the gear ratio multiplies it doesn't add up.

But you miss something important thing here...

given the engines has about 25.7Nm @3600 rpm [13HP]
the first TC has an output torque of about 67 Nm (51 ft lbf);
that is almost the same torque, a Suzuki GSX-R 600 115HP engine provides;
So the second torque converter has to be much bigger than just a Tav2 Kit;
a comet 500 for example or one off a snowmobile maybe...
You'd instantly shred any series 30 or series 40 TC belt with that amount of torque.
That is going to be very expensive...
and, I'm afraid to tell, but AFAIK none of these TCs have overdrive, quite the opposite, they don't even reach 1:1 .. IIRC they end up just like the series 40 at 1.24:1 so 24% "underdrive"...not a big benefit

'sid

 

[Will]

So the torque from the first would just destroy the second tc,
That's interesting haha, although the idea has flaws it was just food for thought.
I think a better way of creating a wider range ratio for the engine would just be changing the driver and the driven for much bigger models, ( bigger in size).

Also, while on the topic of TC's, could I use the gtc 30 series ( the jack shaft ) that mounts to the engine, but instead of running 30 series components, run the 40 series driver and driven on the jack shaft of the 30 series,
Because I am thinking of using a 16 hp motor and The 30 series won't handle the power, but the 40 series can, would this work?

 

[itsid]

the series 40 components are larger than the series30 ones.. and they will not fit on a TAV2 casted backplate.
(I don't know about the steel one, but my best guess is, it's the same center distance)

No matter how big a belt CVT is you mount, you'll always have about the same gearing capacity of more or less 2.5 (2.8 on a series 30 is very much the upper end) a series 40 has a ratio of just 2.59 (44 driver.. even less with a 40 driver)
If you want a larger capacity you have to find a opposite cone CVT matching your engine.
by design a cone CVT has it's 1:1 ratio right in the center of the cones.
So a 2.4 is both 2.4:1 and 1:2.4 ending up in a 4.8 overall capacity.
Personally I don't think that's very useful on a kart though,
since with assumingly 10NM on your cvt output you have to gear extremely high to have a kart still moving (1:15 or something absurd like that) and it simply wont add up to speed

'sid