Help Me To Understand

[Bob Miller]

I was recently intrigued by the performance gains that Sketr2 achieved by putting 20% more twist on the secondary clutch of his Warrior :wink:
So with a little help from my friends (You know who you are!) I changed my secondary spring from a setting of 3+3x10=60% to 2+6x10%=80% twist. :idea:
I know that Sketr2 used a different spring, but I'm going to try it with the stock spring. 8)
I can understand that with more tension on this spring it will take more RPM's to open it all the way, but what I don't understand is this; if the engine at the original setting would pull around 9800-9900 RPM, what would cause the engine to now rev higher to 10200 RPM especially now that it has to work harder to open the secondary all the way :?: :roll:

 

[welterracer]

You answered your own post!!

By having the engine work harder to open the secondary the engine rpms have to go up....To counter act the force of the spring in order to allow the sheaves to separate..

rpms must go up in order to force the spring back alowing the secondary to shift..

if you went to a softer spring it would take less rpms to open..

If yoiu wnet to a stiffer spring it would take more rpms to open

adding twist to the stock spring is like adding more tension or making it stiffer!!

 

[Turk]

You can lose performance by tightening the secondary. What you are doing by tightening it is slowing the upshift. This may help performance on grass but on snow you want to run your secondary as lose as possible with out slipping the belt. On grass with huge traction your secondary will want to go into a higher gear before it is ready. This will cause the belt to slip & put you into a higher gear ratio then you should be in. If you over tighten the secondary you hold back the upshift & lose efficiency. Theoritically you want a combination of just enuff helix combined with spring tension so the secondary will upshift & not slip the belt. On snow you need less secondary tension..on grass a lot more ..or..a shallower helix.

 

[welterracer]

It doesnt hurt to try what you have done.. If it works -it works- if it makes it worse then put it back the way it was..

 

[POWERHAULIC]

Turk nailed it.

The converter should be tuned & adjusted to achieve the desired upshift and backshift characteristics not the desired shift RPM.

Shift RPM should be tuned in the primary

 

[welterracer]

Guys i totally agree with you but his clutching is stock and he want to keep it that way...

Its not going to hurt to try..It has worked for others...He is not pulling enought rpms!!

 

[Turk]

Allways tune rpms by varying the primary weight. Tuning for rpm,s by using the secondary is a quick fix band aid. You might gain rpm,s but you lose a lot of efficiency & will definately lose top speed. Your secondary will also run a lot hotter by holding back the upshift. It is like driving your car at 60 mph on the hi-way in 2nd or 3rd gear.

 

[Bob Miller]

Thanks for the replies I'm taking everything in and I will evaluate this setup in Canada next weekend :wink: I can always put it back to stock!
If I was to put a clutch kit in this STOCK WARRIOR without studs which one would you recommend, and what could I expect from this kit in a stock Warrior without studs compared to stock?

 

[vmaxjohn]

What we would do, and what you're willing to do, could be 2 very different things

Personally, I'd piece together my own set up, and tune the bejeesuz out of it, and make it do everything very well...but! That takes alot of time away from racking up the miles... It seems like there's alot of happy customers of the Speedshop on here, it's always better to go with what works, rather than something untested. That being said, there's nothing to say a prepackaged kit won't require fine tuning to be perfect, every sled is a little different, as well as every tuner.

Welter...you're right, but it needs clarification. With more rpms, the primary spins faster, and creates more shift force. By delaying the secondary upshift, it forces the primary to be farther along on it's shift curve before you hit high gear, you get better backshift too. Like Turk says, if you go too far, you slow down, don't go far enough, and you get stay slow. This is what we love, tuning!

I think it's common knowledge that factory Yamaha clutching desperately needs some balls injected as soon as the sleds hit snow. More backshift is the very first thing to do!

 

[APEX GT 4 STROKER]

Help me Understand

Guys, Isn't it factual the the RX has software in the computer that limits the top attainable RPM until a pre programed milage has been put on this 4 stroke engine ? I'm under the assumption that this is done for warranty purposes to allow for a break in period.

 

[Buckeye]

Break-in

There is nothing like that in my sled. Just change the weights and you can run any RPM's up to the rev limiter.

 

[POWERHAULIC]

There is no break in RPM limiter in this engine.

It will rev. better after it breaks in tho.

 

[SIMMER]

Allways tune rpms by varying the primary weight. Tuning for rpm,s by using the secondary is a quick fix band aid. You might gain rpm,s but you lose a lot of efficiency & will definately lose top speed. Your secondary will also run a lot hotter by holding back the upshift. It is like driving your car at 60 mph on the hi-way in 2nd or 3rd gear.

Ok Turk...Question???

Curious....How many RPM's are gained by tightening the secondary 10 degrees??

 

[vmaxjohn]

I'm not answering for Turk, but thought I'd add my .000005 cents.

It's very hard to predict what wrapping the secondary will get you, rpm wise. If you're set at 50* and are in loose/deep snow, under revving terribly, you might not be close enough with just 10* more for that condition. Do that on hardpack, and you'll see the difference.

Really, as long as you're close the sweet spot, you should technically see the same rpm eventually. Go too far though, and you'll only build heat and slow down.

Thing you need to keep in mind, is that Yamaha send their sleds to the dealers in the most general set up possible. They cannot possibly assume how you'd like your sled to run, or ride, or handle. The secondary wrap is the quickest way to change how your sled responds to different conditions.

Play with it, and see what YOU like