want lower rpm engagement in my 09 M8.....which spring is recommended?

[Bocephus660]

the clutching on my 09 M8 snopro is 100% stock. i had it out in cooke city, mt a few weeks ago, and i hated the way the primary engages. i tested it several times and it will rev to 4300-4500 rpm before it will clamp the belt and start turning the track. i rode my buddies 05 skidoo 800 and i love how you can feather the throttle so the sled "creeps" along if you want it to. it seems as if it would make all of these things easier....

-loading and unloading
-getting out of a "stuck"
-pulling up to the gas pumps
-slow driving around town (like one would do in a cluttered area such as cooke city)
-backing up

i'd say i would like the engagement to be 2500-3000. i dont know if this is possible or not... i know there are dozens of springs out there. i am not 100% sure how to tell one spring from the next, or which brand to go with. what should i be looking for?

 

[pfi572]

You will have to find out the rates on the stock spring. etc 180/360 The 180lb is the start force and the 360lb is the final. Drop the start force to say 130lb or 150lb/360lb and that will lower your engagement if everything else is fine.
The lower the spring force is the quicker the weights start to squeeze the belt as rpm increases so the lower the RPM to engage.
This is just a example as i don't know the spring chart for cat or the colors. Dealer or race manual will have info or maybe some on this thread will speak up and let you know.

 

[tchriste]

Stock spring should be the white/yellow which should be a 122-285.....some people like the cat gold which has lower engagement. With the cat 122-285 I used to have engagement around 4,000. Cat clutches have a few engagement problems which stem from the fly weights and the way they are bolted in, the weights movement is usually impaired by the O-rings. If you take your spring out and move your weights do they move easily? Usually not, so some people either find smaller O-rings or sand the stock O-rings, or leave the nut (on the weight pin) a little looser with good lock tight. Usually it only takes a small amount to free them up, I just installed a smaller O-ring on the nut side of the weight pin.


The other issue with the cat clutch is the fly weights. The clutch is designed with the weights being slightly tucked.


Before doning anything make sure your clutch is clean, inspect weights pins and rollers (mine were gone in 750 miles), then try changing the nut side O-ring.

 

[Team Pigeon]

Ya good advice!

What is you belt to sheave gap? If it's more than .020 with a feeler blade, it should be adjusted. The more gap you have, the larger the spring forces you require for engagement and the more your moveable sheave is going to slap into your belt.
Adjusting can be done two ways.
-have a shop physically remove the spider and change the washer stack.
-buy the thunder products adjustment tool.
On my last 1000 clutch, I had over .040 belt to sheave. My M7 had .070 or something ridiculous. I re-shimmed and bought the thunder kit to make small adjustments as my belt wore. My new clutch didn't need adjusting. I'm not exactly sure if this tucks or untucks weights, but it does lower your engagement rpm. And it does ever so slightly change the position of where your spider initially starts on your weights. Check your belt to sheave first, adjust it if required, test it, worry about what spring rate to buy afterwards. And then bob's your uncle.

 

[sc800]

Lots of great tips here! On my 09 M1000 I changed my primary spring to a AC GOLD and it now engages so soft @ 2950 RPM. Love it!! Check with your dealer or even Glen at Spindrift here on the site regarding the M8 Primary Spring. Mine engages nice and low and yet still pulls my rmps at the finish!

 

[koby]

went a different route on my 09 M8 - Cutler adjustible weights - once you get your weighting right, you can fine tune from toe to heel which has a dramatic effect on engagement.

 

[glengine]

I run the A/C GOLD primary spring in all my cats rental and personal. They work very good. Super smooth and soft engagement, and yet the finish rate is 5lb different than stock. The gold has a sring rate of 75/275.

 

[rigrat]

I second the THUNDER PRODUCTS kit if your belt to sheave clearance is excessive. Easy to install and you can have proper belt to sheave clearance until belt is toast. Super smooth clutch engagement. Best mod i have made on my M series cats.

 

[CatMan16]

I have a gold spring in my m8. I just put it in this season after someone recommended it for softer engagement. It makes it much easier loading on and off the sled deck and I can take off without leaving a trench. I did have a few times that I wished it would rev out a bit more before engaging. On mine it is engaging right at 3000 rpm, if I could find a combination that would have a 3500-3700 rpm I think that would be perfect.

 

[brad6]

Does anyone have a part # for the Gold Primary spring?

 

[Bocephus660]

click link below

DRIVE SYSTEM COMPONENTS

 

[brad6]

Thanka sir! What spring are you guys using in the secondary in conjunction with the Gold Spring in the primary??

 

[sc800]

i am still running stock in my 2009 m1000 secondary and a differrent helix. Also use the dalton adjustable weights.