Nytro MTX sec clutch setting?

[MotoPsycho]

someone post the part number for the purple one please! LOL! ski

The stock spring is 70lb. As you may have found, Cat doesn't make a purple spring, at least that I can find (hardy har har... )

HOWEVER, Cutler, SLP, and some others DO offer purple springs. I dunno exactly which one these guys are talking about, but my best guess is that it is the SLP; rated at 111lb. SLP says the "compression rate is right in between the Arctic Cat Red/White and the Arctic Cat Yellow" (Click for product link)

I have heard a few fellas say to try the red/white, so I would guess this is the purple we need to try.
My buddy has a yellow, so I am going to try it; maybe at 2/0 to begin with.

-Moto

 

[skidooboy]

MotoPsych-o, thanks for the info. i think i'll try the red/white, unless someone can proved the part number and where to find this mystery purple spring so highly sought but not found. ski

 

[MotoPsycho]

MotoPsych-o, thanks for the info. i think i'll try the red/white, unless someone can proved the part number and where to find this mystery purple spring so highly sought but not found. ski

It's amazing, my AC dealer can't find it either. Must be a Canadian part #?

 

[Mcx Nytro]

It's amazing, my AC dealer can't find it either. Must be a Canadian part #?

I think it is but either the red/white will work or even the yellow will be a big improvment

 

[skidooboy]

i cant believe no one will give the part number and where to purchase this purple spring. LOL! i have access to canadian cat dealers if this a canadian only spec. or if it is an aftermarket vendor please feel free to share. enquiring minds want to know. ski

 

[drinkwyo]

i cant believe no one will give the part number and where to purchase this purple spring. LOL! i have access to canadian cat dealers if this a canadian only spec. or if it is an aftermarket vendor please feel free to share. enquiring minds want to know. ski

It is a CPC purple spring. The A/C red white is pretty close to the CPC purple I think

 

[MotoPsycho]

i cant believe no one will give the part number and where to purchase this purple spring. LOL! i have access to canadian cat dealers if this a canadian only spec. or if it is an aftermarket vendor please feel free to share. enquiring minds want to know. ski

The SLP purple can be found: CLICKY HERE

 

[skidooboy]

MotoPsych-o comes through again. thanks bro. i went to cpc but their purple appears to be and "engagement spring" not a driven spring. emailed catdeals.com trying to get 2 sent to me with no response (emailed thursday last week). called local cat dealer, in stock. gonna pick up the red/white spring try it at 0-1 this week. ski

 

[MotoPsycho]

I will be trying both the yellow (@ 40° initially - 1/3) and red/white (@ 10° - 0/1) Thursday and Friday.

Skidooboyedk, Please report back on your findings - I'll do the same. !

- Moto

 

[Nikolai]

I moved mine to 3/6 from 1/6(stock) after a few rides and it was an improvement. I'm going to try the pred/white cat spring out this weekend though.

Does anyone know of a primary spring that's stiffer on top than the stock one(blue/brown). A stiffer finishing rate will also keep the rpms from falling while climbing.

 

[bumblebeast]

Hey sorry about not getting back to you I see you PM me. I'm running the 8bu-oo weights and the same rivet set up. I'm also going to the white secondary spring and going to run itabout 80 degrees with the stock helix I tried the 41 degree helix and it shifted out even earlier. By the way how is your NW turbo working I've got 450 miles now and working well but just trying to get the clutches closer!!

 

[Thistledoo]

The purple spring is made by EPI its part number is ACSS-5*

rate at 2.5 inches is 86lbs
rate at 1 7/16 inches is 148lbs

 

[skidooboy]

thanks thistledoo. dennis kirk has them in their catalog for 12.99.
ski

 

[Thistledoo]

You betchya...snag a couple...keep one for a spare.

 

[skidooboy]

wow, just installed the red/white oem cat spring in there. shouldnt get any slip with that one. you almost need help putting it in by yourself on 0 and 1, LOL!. should give good grip and backshift well. the wire diameter is smaller than the yamaha wire but, the free length is about 50% on the cat spring than the yamaha spring. should torque sense better in theory. will post back next week after our long riding weekend comming up. ski

 

[Nikolai]

The red/white spring is $20 from Cat and the part # is 0648-114 Picked mine up today.

 

[Nikolai]

So what does everyone think of the red/white spring? I rode with mine for the first time yesterday and the backshifting was deffinitely more sensitive and it took less time for the RPM's to get back up after letting off the throttle. I had it in 1,0 and might try adding 10* more.


Has anyone played with primary springs? The blue/brown/blue only has a 110 lb rate(19.6 n/mm). A stiffer spring will hole RPM's better on the hill. The white/white/white spring has alittle less preload and more rate(22.1 n/mm), and the yellow/white/yellow has the same preload as the w/w/w but even more rate(24.5 n/mm). I spin about 9,200 on flat ground and 8,500-8,700 on the hill. If a stiffer primary could keep the RPM's around 8,900 on the hill then you could add alittle more weight to the primary to get back to 8,750(peak HP) and probably pick up some track speed.

Ok, the green/white/green(std in the Can. models) has an even higher rate(27 n/mm or 154 lbs). I'm going to try it tomorrow and I'll report back. I'm hoping it'll hold my RPM's up on the hill to 8,900 or higher. If it does then I can swap out the 13 g. rivets in the tip for the 17 g. and she should be even stronger.

 

[MotoPsycho]

So what does everyone think of the red/white spring?

A vast improvement from stock indeed! I noted:

1. An INCREASE of 400 RPM in the deep (7900 to 8300)
2. An INCREASE of 15 MPH track speed in the deep (from 25 to 40)
3. A DECREASE of 250 RPM on hard pack
4. A top speed DECREASE of about 7 MPH on hard pack (89 to 82)

My sled has right at 425 miles on it, so break in is not fully complete. I will say that I was somewhat disappointed with the deep performance since new, but this spring change has really woke things up. There are still things to be done to increase performance, but it has given me the insight on the potential of this sled.

One additional note: I ran the AC yellow spring at 40° for 1 day, and 60 miles of powder. It offered a marked improvement, however I believe 60-70° would have worked muck better. I didn't continue testing because I had 2 springs, and 2 days, and I wanted to give them equal time with base settings.

I will try the yellow again at higher twist rates as I can, and post results.


If any of you are planning on spring changes, and have run the stock clutch settings very hard (i.e. spring snow conditions, multiple hard, long, powder or hill pulls), I highly recommend taking a spare belt. My stock settings had glazed the belt badly, and it finally gave up several cords on the way back to the trailer the second day.

-Moto

 

[Mcx Nytro]

Are you guys still runnin the stock weights and rollers????

 

[jrusher]

Clutch kit

Put Hartmens clutch kit in... best $400 bucks spent,, different arms, weights rollers, springs and helix.. Woke my sled right up and holds revs now in the deep..and hits hard out of the hole...