Ok I have narrowed it down to a HPD plain primary spring and a violet secondary spring.
No what size wieghts do I need can I keep the stock ones how does it work with the weights heavy engage faster or slower ? and a Helix should I keep stock or a new one I do not have any Idea how these things work Please Help Me ????
I know there is some pretty Intelligent people here that know alot about clutching please Help

In case you do not know I have a 2000 500 Scrambler and I plan on getting a pipe to a White Bros if that helps.

 

I too am looking for the same answers. I also heard that the roller clutches werent "all that" and instead to go with "Black Brute" buttons. a buddy of mine has them on his sleds and his atvs.

 

One thing for sure, if you are attempting to tune your atv clutching without using an accurate tachometer, you are really wasting your time and money. Also, make sure that you do all of your engine modifications first. That will affect the clutching. Even though heavier weights are used, performance does not suffer if the launch rpm is lower. These 4-stroke atv engines develop sufficient low-end torque to launch easily. You can tell when you have too much flyweight, you will start to get a hesitation on launch. There is a lot to tuning these correctly for any given machine. Each one is a bit different based on altitude, air temp, engine modifications, and riding style and in particular, rider weight. It's funny, buy no one ever mentions that for some reason. One setup does not work for all.

All of the aftermarket tuning technology came from the sled clutches. But they are quite different from atv's, in regards to setup. Atv's put out considerably less hp and torque. With most 3-cyl 120+ hp sleds you can't use a really low engagement or the engine will almost stall. Also these sleds don't develop hp at low rpm. A higher rpm engagement helps, to a point. With atv's it is quite different. A high rpm launch is ok for drag racing only, but gives you a much smaller operating range and can be unridable in the woods. This is particularly true of utility atv's like the SP500. They respond well to heavier weights if your engine is modified enough to pull them. I'm well up into the 60's on flyweights and still need more time to get perfect. Most of the aftermarket setups offer higher engagement and higher shiftout rpm. I've tried several and there is nothing worse than trying to creep along on a utility atv with a high engagement. I think that they do this to make the buyer "feel the power", with the higher engagement. You can do the same thing by launching with the throttle and brake engaged to bring the revs up.

Once your clutching is correct the atv will seem almost slower, (by seat of the pants) but much smoother, since it's always in the power band of your engine setup. Every time I've spent the time to get to a straight-line, weight specific setup, the smothness is the first thing noticed. Then with a little fine tuning of the weights from heel to mid to tip and you have found the "sweet spot" for your particular setup. I've used adjustable weights to get the exact setup I want, I'm very fussy about enagement, shiftout and backshifting.

So many people in these forums have stated that this or that particular setup does not work on their atv. It's quite understandable, particularly if their physical body weights are quite different. A setup for a 170 lb. person is different from a setup for a 230 lb. person. I spend many hours getting just the flyweights tuned correctly. You need to be careful not to overshoot your peak rpm shiftout range or performance suffers. We always keep track of a setup with before and after clock times measured over a given distance. It's the only way you can tell if what you did helped, or hurt performance. I've seen many, particularly with roller secondaries, not set up to maximize performance at all. No measured pre-load, etc. Just throw the parts in and run. The tuner weights 230 and the rider weighs 160 and they wonder why it does not work right.

Take the time to start on a known given middle-of-the-road setup from an aftermarket supplier that works. It's best to talk to end users who have tried the setup. Then experiment with different subtle changes. I've found that most of the time Aaen gives pretty good info if you take the time to pull it out of him. Your clutching won't be perfect, but it's a good starting point. There are lots of other tricks you can do once you get the basic setup down. Good luck.

www.godigital-design.com/schultzmotorsports
jackschultz@adelphia.net

 

Great answer! Everybody should check out Jacks website if they havent already, He has some really sweet machines.

 

Thanx Jack very informative
I understand a bit more but the thing that really has me stumped is the helix's I do not Comprehend ramp and stuff.

Could you tell me the diffrence between a:
H44/40P
H40/36P

I know you are a busy guy Jack but could you tell me diffrence between them like engagement which one is faster.
And Backshift which one of those is better backshift I do not mean to bother you with this trivial stuff to you but to me I have no Idea.

Thanx Jack

P.S If you don't have the time to explain this to me could you point me to a sight where I could read up on it.

 

I would take the recommendation of the supplier of the clutch kit that you are going to use. Also, don't mix-and match stuff that you are not sure about. The lower the helix angle, the more belt grip you will get. That's good to a point, if you need it. After that, it can cause inefficiency by gripping more than is necessary. The 42/38 works well under many conditions for most atv's. The acceleration is real good also. Lower angles work under certain specific (drag racing) applications. For an all-around good performer, the 42-38 is a good place to start. You can always experiment with others later. Helix's are quite cheap. Neither helix will affect the enagement rpm. That is governed totally by your drive clutch with the drive spring and flyweights that you are using.

If you want to make clutch changes without a tach, use one of RcR's, HPD's or HS or Aaen's standard setups. I've always thought that each one was quite different from each other. I really don't like the launch rpm of any of them, particularly HPD's or EPI's.

I once had an Erlandson clutch kit on a SP500. I should have saved my money and bought $169 worth of beer instead. All it did was raise the launch rpm and with EBS it slowed up so hard, you could be put over the bars by just backing off the throttle from 30 mph. And they were supposed to be experts with the new (at that time) EBS clutching. We tried three different setups with this kit and finally gave up on it. There was a good recommendation on this kit in Dirty Wheels at the time. So much for their judgement call. They may have gotten it to work on one machine, one time, but that doesn't mean it will work for you.

It worked so lousy that I turned around and bought a standard Polaris clutch setup and we put my favorite drive spring along with a Thunder Shift Kit and an Aaen roller secondary. I have absolutely no regrets, the Thunder/Aaen setup is extremely tunable that will give me the launch rpm, shiftout and backshifting that I'm looking for. The EBS with the EPI setup is still sitting gathering dust. I just hate how they perform.


I would take the recommendation of the supplier of the clutch kit that you are going to use. Also, don't mix-and match stuff that you are not sure about. The lower the helix angle, the more belt grip you will get. That's good to a point, if you need it. After that, it can cause inefficiency by gripping more than is necessary. The 42/38 works well under many conditions for most atv's. The acceleration is real good also. Lower angles work under certain specific (drag racing) applications. For an all-around good performer, the 42-38 is a good place to start. You can always experiment with others later. Helix's are quite cheap. Neither helix will affect the enagement rpm. That is governed totally by your drive clutch with the drive spring and flyweights that you are using.

If you want to make clutch changes without a tach, use one of RcR's, HPD's or HS or Aaen's standard setups. I've always thought that each one was quite different from each other. I really don't like the launch rpm of any of them, particularly HPD's or EPI's.

I once had an Erlandson clutch kit on a SP500. I should have saved my money and bought $169 worth of beer instead. All it did was raise the launch rpm and with EBS it slowed up so hard, you could be put over the bars by just backing off the throttle from 30 mph. And they were supposed to be experts with the new (at that time) EBS clutching. We tried three different setups with this kit and finally gave up on it. There was a good recommendation on this kit in Dirty Wheels at the time. So much for their judgement call. They may have gotten it to work on one machine, one time, but that doesn't mean it will work for you.

It pissed me off so much that I turned around and bought a standard Polaris clutch setup and we put my favorite spring along with a Thunder Shift Kit and an Aaen roller seconday. I have absolutely no regrets, the Thunder/Aaen setup is extremely tunable that will give me the launch rpm, shiftout and backshifting that I'm looking for. The EBS with the PI setup is still sitting gathering dust. I just hate how they perform.

 

Thank you very much Jack .......
I appreciate your comments.

Have a good one