I have a friend that has just bought two new 300 Polaris, the new one that they just came out with. I was reading his owners manual and it said that along with carb jet changes for high altitude he needed to change the weights in his CVT drive. I of coarse understand the need for the carb jet changes but I am new to CVTs. I realize that weight changes will affect the rpm that the CVT will begin to engage, but how is this affected by altitude? Also how does the "EBS" work? I have noticed that the system will completely stop other Polars on a downhill that I have ridden. This would take a lot off getting used to for me as I am used to the true engine brakeing that is used on Arctic Cats, by utilizing a sprag clutch in the CVT. Is the CVT braking on the Polars adjustable. I have seen people get out of shape on long rocky downhills when the rear wheels lock up with this system, and there is no CVT braking to the front wheels on a Polaris. This seems like a crude system for a company as innovative as Polaris. I must be over looking something.

 

You can easily bipass the ebs on the Polaris atv's by feathering the throttle while going downhill. This will release the ebs and basically freespin. Then you can use your brakes to go slow downhill.

 

I second the last post and it is possible to force all wheel engine braking. Pull up to the edge of the hill slightly on the down hill side.
LOOK BEHIND YOU - make sure it is safe to back up!
Put the ATV in reverse, HOLD the reverse over-ride button, and give it enough throttle to make the rear tires break loose (and engage AWD in reverse).
Select low range or high range as needed, depending on how steep the slope is, and let it just idle down the hill. Beware - if you feel like it is going too slow and you give it a little gas, the AWD will disengage! it's a pain in the a$$, but it is possible.

peace

 

the above statement is very bad for your hillard central clutch though, dont do that alot or your money is going to be leaving you fast

 

listen to this dude! he knows about money leaving your pocket.[img]i/expressions/face-icon-small-wink.gif[/img]

 

I found this letter on another forum, a guy wrote to Hillard and this is the response concerning forced AWD engine braking:

The condition that you are asking about above is called "wedging". What you are doing is locking the rolls in the reverse profile of the clutch (it is a bi-directional clutch set-up) and proceeding in the forward direction thus not allowing the clutch to overrun (which is the normal condition). This in turn locks up the drive train and makes the system steer like a fully locked differential. This condition is

Advantageous if going down a steep hill because it will only allow the front wheels to move as fast as the drive train. This will fully utilize the engine brake because when going downhill the weight distribution of the bike goes to the front end and that is where you want the majority of your traction.

This "wedging" will not hurt the front gear case, but it could accelerate the wear of the drive train components (such as the front prop shaft) because it does completely bind up the system and the bike will be very difficult to steer. Because of the binding and additional steering effort, neither Hilliard nor Polaris will recommend doing this.

You can get the system out of the "wedging" condition without turning the power off to the AWD system, but it is very difficult and not always repeatable. The only true, 100% way to release the clutch is to turn the power off and put the bike in reverse. This will release the pressure on the clutch and the springs inside the clutch will return the rollers back to the neutral position.

To answer #3, there is no way to drive the front wheels at the same time as the rear wheels without the rear wheels slipping. The bike is geared to have a 20% speed difference from the back to the front.

This means that it takes the rear wheel to slip or spin 20% (1/5th of a rear tire revolution) before the front wheel to drive the system. This is necessary to give the bike a tight turning radius and to prevent the bike from automatically "wedging". If the front to rear ratio was 1:1, every time you turn the handle bars even slightly, the front wheels would act like they have a fully locked differential and it would take you 30 feet to turn a 90 degree turn (like driving a new Kawasaki Prairie with the front gearcase locked). Because when you turn, all of the wheels on the bike are now moving at different speeds dictated by the ground speed, and the front clutch would not be able to overrun. With the 20% speed difference, the AWD can be on all the time and it will only be there when you need it. You won't get any of the side effects of all the other systems that don't allow you to turn the 4wd on and off. Basically, having the front wheels driving the same speed as the rear wheels would be like driving a tank and would be hard on the arms
and not very fun.

I hope I have answered all of your questions and not confused you to much. Browse through the overrunning clutch section on the Hilliard web site (http://www.hilliardcorp.com) for more info on how overrunning clutches work if you have any more questions. Have a good day.

Thanks,

Matt Cowen

Engineering Product Manager

Drive Train Products

Hilliard Corporation

 

well, since its from hillard themselfs. ive always been told/tought/round' the campfire that it wasnt good at all. but in any sence, the clutch peices are expensive, breaking them is expensive