[Crash City SxS]

BEFORE- ‘17 XPT buggy. 2seater transmission. 32” roctane x2 Stock gearing. AA high load clutch kit. ‘19 XPT4 32” roctane x2’s stock gearing and AA high load clutch kit. Had performance helix before high load but switched to try and keep from eating belts. Both units ended up eating belts no matter the helix.

IN NO WAY ARE WE BASHING MIKE OR AA IN THIS POST. He’sbeen great to work with solving a couple turbo problems we’ve had and we will continue to buy products from him and his company. Just throwing this out there for others fighting their clutching like we have.

for a year we’ve been playing with weights per AA with no luck. On stage3 tune we fought to keep rpms within the acceptable ranges. Had to go all out with 4/4/4/1 weights to get rpms calmed down. Still eating belts breakfast lunch and dinner.

So we installed the 53% reduction in both units as we switched to 35” roxxzillas know the belt situation wouldn’t get any better and if you’re running that size and weight of tire you need the reduction. Put performance helix instead of high load since the reduction takes care of that and went 4/3/2 as a starting point. Boom. Test drove and rpm jumping all over place. Added weight rpm jumping all over the place.

spent a week studying up on the black magic of clutch tuning. Talked to different companies and they all only wanted to sell me something except Todd at hunter works. He explained how it all works and didn’t try to sell me anything. Thank you sir for the info and education.

so thinking of all I’ve learned went back to assess our situation. Led me to think the secondary spring is too soft. Replaced AA purple spring which i do believe is 150/265 with a venom 160/200 in her buggy. AA doesn’t tell you their spring rates or angles so it’s an educated guess. I could be wrong. Test drove and FINALLY it held steady at 8200 rpm with 4/4/4 in the flyweights. Replaced xpt4 secondary spring with venom 185/245 as it was eating belts more I assume from being heavier than hers.

so for our crawling/difficult trail riding went with this setup I believe is going to give us most grip. if anyone sees a problem with this please tell me and show me the way.

Both have oem primary spring AA flyweights set at 4/4/4.
hers being lighter has 55* straight aa performance helix with the spring listed above.
mine has oem 53-49 progressive oem helix (aa 55 performance helix will be ordered) with venom 185/245 secondary spring.
Went with oem primary spring so engagement grabs to belt with a little more umph and the heavy flyweights to grip the belt hard.

Tip weight also affects heal weight so ends up or engagement comes in much smoother than before around 1800rpm. Setup pulls hard with no belt slip yet. Both setups considerably cooler to touch sheaves after riding than before. The xpt4 being even cooler to the touch than her buggy.
We’ve installed after reduction a Razorback belt temp gauge from @craigstumph. He was 40$ cheaper than anywhere else. So now we can keep an eye on temps as we further test this setup out on the rocks.

I guess throughout this I’m thinking most clutch kits are very similar and need to be fine tuned for your specific riding. What works for us may not work for you and vice versa.
if you aren’t happy with your setup don’t get rid of it to buy another. You may just need to fine tune it to what you want it to do.

please add info if I’m incorrect or add any other info as clutching companies seem to like to keep their secrets

 

[Crash City SxS]

So on the gear reduction...
It’s a must have imo for 35’s. All we have to test it out on is a little 2 foot tall retaining wall at our house. Before reduction and clutch tuning our units would just sit there and smoke belts. After reduction and tuning both RZRs climbed right up on it with super ease at just the slightest little touch of the skinny pedal. Super smooth engagement and feels like we have 1000% more control and precision than before. Can’t wait to try them out on the trail.

Upgraded her buggy axles to @SuperATV Rhino 2.0. Thanks for the forum hookup! We figure with tires and reduction we’re going to find some weak links along the way.

 

[Crash City SxS]

 

[Max H]

I have tried to suggest this MANY times ... most people dont need a clutch kit when increasing tires size from say stock to 32's ...they just need to bump up the secondary spring rate to help hold it higher in the secondary longer and help reduce belt slip. It also adds some RPM without adding weight, this helps counter act some of the power loss from the larger tires. Of course this doesn't work for all ...but does for most all riding trails and other.
If you still cant get enough RPM then I would look to adjust weights and I would recommend weights that have a good amount of heel weight built into the profile. I personally like weights that can be adjusted without removing them ..like set screw style Magnum weight from SLP ...it gets old real quick pulling the weights and changing magnets all the time

Here is the 2 secondary springs EPI sells...

The Grey is very universal almost perfect for most anyone stepping up to 32's from stock. This is the one I recommend in most situations

The Teal is more for your super heavy weight machines , rock crawling , big power , 35's ...or all combined ..think Hi load

Fits:
RZR XP Turbo 16-20
RZR XP 4 Turbo 16-20
RZR XP Turbo S 18-20
RZR XP 4 Turbo S 19-20
1000 RZR RS1 18-20

Color	Part #​	2 1/2" Load​	1 1/4" Load​
Teal	PEBS30​	182 lbs​	260 lbs​
Gray	PEBS29​	168 lbs​	240 lbs​

Of course there are a lot more adjustments that can be made but the secondary is the easiest to replace , its cheap and almost always is an improvement when weight or larger / heavier tires are added ...IMO the best place to start

 

[Crash City SxS]

Yes that’s a great thought and brings up an example in my case. Xpt4 stock on 32” tires. Hit a tiny ledge 2-3’ and when rears we’re trying to climb It the belt slipped. My first thought as everyone’s was dang I need a clutch kit. Now I had more mods and high hp coming so it eventually justified a clutch kit.

now with a far greater understanding of cvt tuning all I needed at the time was the spring you speak of. 32” tires are the norm now and if someone doesn’t want any bigger than that or more hp then stiffening up the secondary spring like you say is a GREAT $25 dollar starting point.
I feel your pain on changing the weights around nonstop!!!

 

[gfourth]

@Max H , how does this spring compare to what comes in the AA S3 kit?

 

[Crash City SxS]

The purple spring I believe is a 150/265 from aa stage 3. So any of the stiffer springs mentioned above start out stiffer than aa but finish rate is similar. More belt squeeze than aa spring starting out.

stiffer secondary spring provides more resistance to the helix trying to open up the secondary. So it opens up slower as the primary keeps trying to pull the belt down into the secondary producing harder tighter belt grip.

 

[Max H]

@gfourth Its been a long time since I ran the AA clutch kit I really dont remember , but I think Crash City is probably correct ?
On a separate note... If anyone want to buy an AA S3 performance helix I have a good used one for sale

 

[marcshack94]

I have 32 inch tires on the pro xp. I felt belt slip a few times in the 20 to 50 mph range. already rolling about 20 and hit the throttle to accelerate and the belt slips. would doing the secondary spring like mentioned above solve some of that problem? I eventually want to do gear reduction because the pro xp is way to tall in low I think, but for now a 25 dollar spring sure sounds a heck of a lot better. On stock clutch btw with no engine mods except hard intake tube.

 

[Max H]

I have absolutely no experience with the Pro clutching ...but that is what Polaris did on the first fix / recall with the Pro XP....they increased the secondary spring rate to reduce the slip . The XP pro clutch , maybe a whole new animal. But I doubt it is totally different
Good question ....I think a stronger secondary spring rate might be necessary especially after pumping a stage 3 flash or +HP tune

 

[Crash City SxS]

We’ve not messed with a pro xp yet either. Same principles should apply unless there’s something not quite right yet in the primary in the new clutch. Wouldn’t hurt to beef up secondary spring and think if you would still experience some slip than that would point to tweaking the primary with some weights.

 

[Crash City SxS]

Why we did the reduction, how to change the gears out, and how to get a stuck primary off your rzr...

 

[clemson726]

Why we did the reduction, how to change the gears out, and how to get a stuck primary off your rzr...

Does anyone know if the internals are the same in this video as in the Pro?

 

[Crash City SxS]

I think they are the same but not 100% sure. I’ve seen a recent thread pro xp gear reduction is where I think I saw it. Try looking that up. If so...

 

[SNWMBL]

Sub’d. I’ve ran the gray EPI spring for a few rides and like it, going to give the teal a try.

 

[Crash City SxS]

I never felt the need to understand clutching obviously until We ran into belt issues on our turbos. Watched a lot of videos, read a lot of articles and then sat back and let it all sink in.
My problem understanding it, the clutching block in my head, was that everything I saw made me feel that the whole system had to mesh together to work properly. Which it kind of does but not really. Using clutching terms like up shifting and back shifting made me feel that both clutches had to be married together to achieve your goals.
And I felt they tried to describe it that way.
Once it hit me to look at it that they have separate duties and the belts just there for the party, I understood it better.
I totally see now what @Max H has been saying about the secondary being the best place to start tuning.

 

[Max H]

Its not always the best place to start it just depends on the problem ...you are correct it does all have to work together.
Every situation is a little different...for example lets see what Polaris does with the latest recall they just announced today with the Pro XP style clutch ?

 

[Crash City SxS]

I’ve not seen the recall yet. I’ll have to check it out

 

[Max H]

Another recall ....XP Pro type clutches

Well better late than never ...... Hopefully they finish R&D on the clutching this time and Fix it !!!

www.rzrforums.net

 

[Crash City SxS]

So got some video edited. I know the ledge isn’t much but when we hit it before with no gear reduction and poorly tuned clutch you could smell belt by the time we hopped up on it. Trail testing our setups tomorrow to check belt temps and hopefully no slip.