BryceGTX,
have you ever ridden a utility ATV with a high rpm clutch engagement? I'm just wondering, because they are no fun at all. I did a lot of experimenting with clutch tuning on v-force and prairie ATVs.

I spent a whole day once doing timed runs up Sand Mountain, which is a 700' high, really steep mountain of sand. I wanted to see which clutch combination would produce the fastest times. I tried four different springs and three combinations of clutch weights in one day. I found that on a V-force a spring with a higher stall rating helped prevent wheelies. I could just pin the throttle off the line, and RPMs would build high enough that when the clutch engaged it would spin the paddle tires, instead of relying on torque, which caused wheelies. A spring with a higher shift out rating allowed higher RPM once running up the mountain, and the engine would pull the hill faster when revved higher. I was able to shave 6 seconds off my time, which is HUGE. Watch a quad climbing the mountain near the top, when it is at top speed, and see how much ground it covers while you count out 6 seconds. Lose that 6 seconds and it puts you way way behind.

I do not think utility quads respond as well to clutch tuning. The best engagement RPM for a utility quad is stock. Raising the engagement RPM makes it hit a lot harder when it engages, which ain't cool while climbing the side of a mountain and trying to keep the front end down. And it is worse in reverse; you have to rev the engine to about half throttle to even get it to engage, then it bangs hard when it hooks up. Try that why backing out of your truck on a snow covered ramp someday [img]i/expressions/face-icon-small-shocked.gif[/img] . You also loose engine braking while going downhill with high stall springs, because as soon as you drop the RPM below engagement speed, it disengages. High stall springs just don't work for general utility ATVing. Although I did find a spring with stock engagement RPM and a little higher shift out RPM that was pretty nice on the Prairie, but that was still a compromise.

I don't know if Polaris transmission have the same characteristics as a Kawasaki, because all I ever did to the clutch of a Polaris is change to high altitude clutch weights on a Scrambler 500 4x4, and it didn't seem to do much of anything for it. In fact, it may have slowed it down a bit; it certainly didn't help. I did change to a stiffer secondary spring in a Yamaha Grizzly once, and it helped speed up backshifting, and made it feel more responsive in general.

And another thing, this thread asked what is the most reliable belt drive transmission, not which one is the best. The word best is subject to interpretation, but most reliable is simply a statistic. If we could find statistics on percentage of total belt drive transmissions that require repair for each manufacturer we could answer the question definitively. Not only could we say which is the most reliable, we could even list them in order from most reliable to least reliable.

DV

 

I don't see in this thread where it requires us to only talk about UTEs. I don't drive UTEs. So whats your point?
The V force has so much torque that it almost does not matter how you clutch it. (Compared to a two stroke) But I can believe that you can find an optimal clutching for sand. This supports my arguments. But I think you mean a slower shift out rate, thats why it was running higher revs. However, try running a 250 Trailblazer or a 330 Trailboss up sand hills. Then again, try racing a CVT quad or building up a two stroke CVT. Then you will understand why people change their clutching on these quads.
It all depends on how you are going to use your quad. If you need a high performance CVT system, for whatever reason, you will reclutch it. Just because you have never found the need doesn't mean all people haven't found the need. I personally spend a lot of time on goat trails, so the stock clutching is fine. However; in the dunes, it is clearly lacking. The other application where UTEs change their clutching is for mud.
You do not lose engine braking on either a Polaris or a Yamaha because these systems use one way overrunning clutches to transfer torque back from the wheels to the engine. The clutching has little effect on engine braking.
My first post, I specifically said "I prefer the Polaris system". This is my personal preference. I don't remember saying that any system is best. As far as statistics.. I can make anything look good or bad with statistics! Statistics asre only as good as the underlying assumptions.
Bryce

 

"The V force has so much torque that it almost does not matter how you clutch it."

I've been trying to give you the benefit of the doubt on this thread, but you have never done any clutch tuning on a V-Force. Why do you come on here with these bold sweeping statements about something that you have no experience with? I'm sorry if this is offensive. If this were subjective we would have a disagreement. Its objective, and you're just wrong.

You say you "prefer" the Polaris belt drive system. Prefer to what? What other belt drive ATVs have you owned that you prefer the Polaris system to? Or is everything you say just a regurgitation from a Polaris sales brochure. If I wanted to know what the brochure said I would go to a Polaris dealer.

propnut was right when he said not to waste our time.

 

I'm crushed

 

>>>>>>>>>>>>&g t;>>>>>>>>>>>> >>>>>>>>>>>>&g t;>>>>>>>>>>>> >>>>>>



LOL!!!!!

 

just because you haven't owned doesn't mean you haven't tried one out or worked on a freinds. And most people have to get it through their thick heads. If you ride a polaris there is a good chance he is a tuner. not just some guy who putts down the trail checking out the butterflies

 

I ride Polaris and have never had any trouble with a belt. I have smoked my belt on a few occasions trying to haul people out of mudholes but this has been more a result of light throttle application and/or being too close or tight on the winch cable. Even then there has been no probs with the belt afterward. I ride with all different makes of quads and actually have not seen a belt problem with any of them. We are by no means gentle on our bikes but there have been no problems with my group of riding buddies. Snowmobiles on the other hand are a different issue and I have experienced chunked belts, glazed belts, blown belts over the years and witnessed the same with a lot of other people across all sled brands using all types of belts. So to me the quad systems are easier on belts or the belts are built better than sled belts.