Clutch Testing

[84td]

I have been searching around online, it seems like alot of the aatv's and even snowmobiles share a similar clutch/torque converter setup. Mine is not working properly, its only getting about half movement. Is there a way to test these, preferably on the machine, to see which one is not working right?

[Mike]

What do you mean by half movement? Are you saying that only one side of the clutch is moving? If so, that is how they are supposed to operate. Only one sheave will move on each CVT. If you have your machine in neutral, you can rev the motor and watch the two CVTs work so that you can tell if they are operating properly.

Here is a video showing how the clutches should operate:

[84td]

Thanks for the video. That helped a lot. My clutch could be working ok I guess. In that video the belt never makes it to the top of the primary. Mine only makes it about 3/4 of the way as well. I guess that's normal?

Is it also normal for these aatv's to be about the same speed as a riding lawn mower?

I need to make it to an event and see other people's rigs.

[JohnF]

I don't know what machine you have.

I will assume that you noticed how the belt sat in the pulleys when nothing was moving and that this pretty much matches yours, that is, your belt isn't super loose/too long which could be the cause of your observed performance. It would also engage at a high RPM.

Another reason you may not be getting full **** out would be that your engine isn't producing the power that the CVT is tuned for. An engine problem or the masses in the drive pulley are too light.

When designing a vehicle with a CVT the designer will call for a specific ratio for CVT full shift out, like 1:1. Watching the video, it looks like that CVT might overdrive a tiny bit but it is at least 1:1. You should see something similar when you watch yours while in neutral and at full shift out. Does it look 1:1?

Then I would, with great care, remove the cover and make a straight and level run at wide open throttle to see if I get full shift out. If you have a go pro or similar it can be done easier and safer. If you get full shift out then you now know your top end speed. To get more you'll need to do something to the overall gearing.

If it didn't shift out, then you need to tune your clutch or fix your engine.

As a speed data point: My conquest has seen 17MPH GPS on the straight and level at about 2000ft elevation.

[Nubs]

Nice video Boss man Mike, There needed to be a thread dedicated to the CVT clutches in Our machines. Hopefully We can All add to this as time goes by

[liflod]

I wouldn't rule out the belt being too lose or worn out.

[riotwarrior]

Great video,

Ya what machine, what engine are you working on here OP?

[Nubs]

Just adding a picture of the comet 780 with its lid off.

[Nubs]

Sexy Yes