CVT on a kart...

Joshua (BlueBayou) Lyon · Posted: Tue Jan 15, 2008 5:50 pm Post subject: CVT on a kart...

Hi everybody,

link: http://www.kartetpantera.com/news_galerie_news_2006.html (4th item down). It looks like someone is developing a CVT for karting. Does anyone know anything about it?

*EDIT*

Apparently it was at the Intertational Kart Expo (last year I think): http://www.kartsportnews.com/feat_germanexpo06.html (11th item down - middle of page). Does anyone know how it performs on track?
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Catch U Later - Joshua

Brian G. Wilson · Posted: Tue Jan 15, 2008 6:05 pm Post subject:

Now, I may have to admit that I'm not the most technically advanced and the simplicity of karting was one of the things that attracted me. In the 4th picture down, I see what look like red hydraulic or high pressure hoses at the front of the engine. Is that what your talking about? If so, what is a CVT and what value would it have to karting?
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Joshua (BlueBayou) Lyon · Posted: Tue Jan 15, 2008 6:10 pm Post subject:

Chad Stapleton · Joined: 19 Jul 2001 Posts: 4403

This was the unit Joshua was refering to.

it was developed for the Rotax motors in the UK a few years back, and apparently works very well.
But it is expensive and as there is no class that allows it to race..... it has not been a big seller
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Chad
"Those of you who think you know everything are annoying to those of us who do !!"

Scott Heavin · Posted: Tue Jan 15, 2008 6:49 pm Post subject:

I was at the Indy Auto Show a few weeks ago and was surprised how many manufacturers were offering CVT.
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Chuck Parker · Posted: Tue Jan 15, 2008 7:05 pm Post subject:

Pop the hood on just about any snow machine and you'll see something simliar. I think some Polaris atv's use to use a cvt

Francis Amargo · Posted: Tue Jan 15, 2008 7:07 pm Post subject:

Must be the same CVT system reviewed by karting1.co.uk

Youtube - Karting CVT system

Rick Blood · Posted: Tue Jan 15, 2008 7:55 pm Post subject:

The original name was "infinite ratio torque sensitive constant speed drive system". The advantages are obvious but the drawbacks are huge.
The system relies on the pinching of the belt by the drive pulley to pull on the belt which forces it's self down ito the driven pulley and changing the ratio. The pinching in the two pulleys drags a huge amount of power away from the axle. The benefits don't outway the disadvantages when everyone in a class is at 25 HP and you are wasting 4 or 5 HP just so you can get off the corner better.
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Steve O'Hara · Posted: Wed Jan 16, 2008 12:39 am Post subject:

That looks like the systemI had on my Mac 91 powered Taco mini bike in 1971... not exactly modern technology. It worked great at times but not very consistent. Not the same approach as the car manufacturers have been developing recently
I hope they never catch on in karting..... race vehicles just don't sound right with the motor running at a constant speed.
Steve O'Hara

Chad Stapleton · Joined: 19 Jul 2001 Posts: 4403

Arn't Comet's "Torque -converter's " used on most mini drag cars ?..
...and have been available for 20 yrs +
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Chad
"Those of you who think you know everything are annoying to those of us who do !!"

Christos Segounas · Posted: Thu Jan 17, 2008 2:44 pm Post subject:

I like the theory behind this system but I don't want to see any more weight on karts even if it means they will accelerate faster.
I'd rather someone came up with a viable idea to reduce weight on karts, that would make them both faster and much more pleasurable and exciting to drive, plus much safer.
Still, if we put single gear karts aside, I don't know how much this weighs compared to a gearbox but gearbox karts aren't lacking in acceleration anyway.
I once tried to push start my 100cc kart as usual, some 16 years ago but the throttle return spring had broken.
I ended up flat on my face and the kart accelerated away at a pace that suggested low rpm performance wasn't an issue after all.
Weight was. Smile

Rich Kay · Posted: Fri Jan 18, 2008 7:43 pm Post subject:

Tyler Walsh · Joined: 03 Apr 2006 Posts: 1016

even williams tested them
http://www.youtube.com/watch?v=x3UpBKXMRto
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John Denman · Posted: Sat Jan 19, 2008 2:59 pm Post subject:

We had several Honda FL350's & FL400's between 1986 and 1998 all using a belt driven CVT.

Stout units and very effective. Belts last much longer then any dry clutch will, and they're relatively cheap.

They would require a jackshaft on a kart and that adds just enough complexity that no one uses them.

Now take the Aixro and couple it to a Comet CVT........
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Producer for RTMP
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David Cosper · Posted: Sat Jan 19, 2008 8:00 pm Post subject:

Here is the kart CVT in action.

http://www.youtube.com/watch?v=PWkpLrnAjEU&feature=related