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M858 clutch kits?

I havent. The 155-220 spring worked a lot better for the 46. Primary shifted much further out. Probably 1/2" more at least
 
So this is going to be a long post. I'm hoping you guys can help me learn a little more on this clutching business. I know there's lots of ways to get almost the same results. I'm open to any advice you guys are willing to give me.

858 154 3 inch. I didn't even ride the factory clutching based on what I've heard. I bought a setup from BDX and it seems pretty good but I'd like the clutch to engage a bit lower than 4000 rpm. When loading and unloading, as well as when trying to pass slowly and nicely when you meet xcountry skiers/hikers 4000 just seems a bit fast. Seems to chatter a bit (engaging/disengaging) when I try to travel at that speed. My only riding so far is the Black Hills at 6-7k feet. I saw 8250 rpm and it seemed to have more left but I didn't want to push it anymore which makes sense for the lower elevation. I normally ride 9-10k or a bit more (Snowies/Bighorns/Steamboat). I do have a Jaws trail can, and right or wrong the ring behind the primary may be in my toolbox. Heres the setup.

Magnetic weights 60 gram base with 4 magnets. 1.3 grams each so 65.2 grams. Distribution from the heel of 2-1-1-0.

125-290 Primary Spring

190-260 Secondary Spring

Helix is a 7TM-52/40.20

Thanks.


Edit: What could I expect with a 105-280 Spring? From what I gather engagement woukd be lower but what will I see on the upper end a little less spring?

Edit #2: Ordered the 105-280. I also ordered a Thunder Products primary spring washer set. Going to try 1 glide washer plus the lighter spring. I feel like I should try to keep the finish rate similar. Hoping the 1 washer will help that. Hoping for 3600ish engagement. I think I'll also pull one weight and run 2-1-0-0 and test when I'm in the Bighorns in a couple weeks.
 

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Sofar this is my findings/thoughts but this is for the 3-7000’ club. Sorry in advance for the long post.

The 48* stock helix with the stock 180/240 spring seems to have enough backshift everywhere. I don’t ever seem to be short on RPM even on/off throttle at load. This makes me think the need for any angles <48* should not be necessary or else you will just need more weight in the primary just to pull the rpm back down as you restrict upshift and you increase RPM with shallower angles. Unless you went with shallow angle and less spring weight.

The stock weights out of the crate were 62g primary spring is a 85/255. This gave 83-8500 rpm with the engagement somewhere around 3500rpm. I seemed to have good luck with Bikeman Snyper weights on my 2017 so in went another set. With the 4576 snypers I ended up at what is supposed to add up to 64.9g. Tungsten at the tip followed by the large set screw and a small. 3/3 for magnets.

This improved upshift a ton, accelerating/pulling way harder than stock. Engagement rose to 4000RPM but didn’t feel bad or seem to produce much slip in slow bush action. I accredit this to loading the tip of the weight, in theory this will delay the engagement but provide aggressive up shift. Top end feels like it’s in the money at 81-8200 RPM. I know early dyno sheets show HP at lower RPM but this is where my butt dyno tells me it’s good hahaha. This to me would lead me to believe there is no need for any spring heavier/stiffer than stock to achieve things or else I would just need more weight to pull RPM back down.

Another fella I ride with has a Bikeman helix, can’t remember which one at the moment. But he’s achieved nearly the same results but with a few less grams of weight. This would lead me to believe the helix is a split or progressive living somewhere between 56-46* rather it be 50/46 or 52/48 etc, etc, you get the point.
 
Is anyone running the full speedwerx kit? The secondary helix thats in it is TBH 64-49-30 ER. So its a compound cut i believe starting at 64 then moving to 49 after .3
 
Sofar this is my findings/thoughts but this is for the 3-7000’ club. Sorry in advance for the long post.

The 48* stock helix with the stock 180/240 spring seems to have enough backshift everywhere. I don’t ever seem to be short on RPM even on/off throttle at load. This makes me think the need for any angles <48* should not be necessary or else you will just need more weight in the primary just to pull the rpm back down as you restrict upshift and you increase RPM with shallower angles. Unless you went with shallow angle and less spring weight.

The stock weights out of the crate were 62g primary spring is a 85/255. This gave 83-8500 rpm with the engagement somewhere around 3500rpm. I seemed to have good luck with Bikeman Snyper weights on my 2017 so in went another set. With the 4576 snypers I ended up at what is supposed to add up to 64.9g. Tungsten at the tip followed by the large set screw and a small. 3/3 for magnets.

This improved upshift a ton, accelerating/pulling way harder than stock. Engagement rose to 4000RPM but didn’t feel bad or seem to produce much slip in slow bush action. I accredit this to loading the tip of the weight, in theory this will delay the engagement but provide aggressive up shift. Top end feels like it’s in the money at 81-8200 RPM. I know early dyno sheets show HP at lower RPM but this is where my butt dyno tells me it’s good hahaha. This to me would lead me to believe there is no need for any spring heavier/stiffer than stock to achieve things or else I would just need more weight to pull RPM back down.

Another fella I ride with has a Bikeman helix, can’t remember which one at the moment. But he’s achieved nearly the same results but with a few less grams of weight. This would lead me to believe the helix is a split or progressive living somewhere between 56-46* rather it be 50/46 or 52/48 etc, etc, you get the point.
My primary spring is 120-265 is yours from a 858? Also AC calls for 8100-8200 rpm probably why the butt dyno feels good there.
 
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Finally got a ride on my Ibexx kit set up to their baseline settings for 8000+ elevation, was riding mostly between 8-9000ft. Smooth engagement around 3500rpm. It definitely feels more responsive on bottom, and on and off the throttle and hits peak rpm almost instantly and holds it better than the stock set up did. Was over revving a bit at 82-8300, occasionally 8350, especially first thing in the morning when the springs were new, but seemed to drop down to around 82-8250 later in the day. Granted the snow was a bit heavier than the last ride, but I didn’t think it felt like it pulled quite as good on the top end as the stock set up and wot track speed in a climb seemed to be down about 5mph from what I remember on the last ride with stock stuff.

The kit is magnet style weights, mystery helix with no angles written on it that I remember seeing, and what appears to be bdx springs. If they’re bdx, then it’s the 105/280 orange primary spring, and their 190/260 secondary spring. Their instructions had me put all the magnets in the two closest holes to the pin leaving the two holes closer to the tip empty. Now in my quest to bring the rpm down 100 or so and try and get a bit of the top end pull back without losing the bottom end response, I’m trying to decide if it would be to much to just add a 1/2 magnet towards the tip on top of what I have or if it would give me the outcome I’m looking for by moving a magnet or 1/2 magnet farther out. This is my first time playing with mag style weights, so I’m not sure how drastic of a change moving/adding a magnet will make.
 
Finally got a ride on my Ibexx kit set up to their baseline settings for 8000+ elevation, was riding mostly between 8-9000ft. Smooth engagement around 3500rpm. It definitely feels more responsive on bottom, and on and off the throttle and hits peak rpm almost instantly and holds it better than the stock set up did. Was over revving a bit at 82-8300, occasionally 8350, especially first thing in the morning when the springs were new, but seemed to drop down to around 82-8250 later in the day. Granted the snow was a bit heavier than the last ride, but I didn’t think it felt like it pulled quite as good on the top end as the stock set up and wot track speed in a climb seemed to be down about 5mph from what I remember on the last ride with stock stuff.

The kit is magnet style weights, mystery helix with no angles written on it that I remember seeing, and what appears to be bdx springs. If they’re bdx, then it’s the 105/280 orange primary spring, and their 190/260 secondary spring. Their instructions had me put all the magnets in the two closest holes to the pin leaving the two holes closer to the tip empty. Now in my quest to bring the rpm down 100 or so and try and get a bit of the top end pull back without losing the bottom end response, I’m trying to decide if it would be to much to just add a 1/2 magnet towards the tip on top of what I have or if it would give me the outcome I’m looking for by moving a magnet or 1/2 magnet farther out. This is my first time playing with mag style weights, so I’m not sure how drastic of a change moving/adding a magnet will make.
I have a 165 3” completely stock. Never had any bog issues at all. I put the ibexx kit in this weekend (clutching only). I talked to one of their guys on the phone who recommended 3-1-0-0 heel to toe. Riding 5000-8000’. His recommendation was not even close to being what it should be. It was over reviving so bad I could hardly ride it on the trail. It kept putting it in limp mode. I ended up adding way more weight. Now it’s 3-2-2-2 all 1.7g magnets. It’s way better now. I bought the ibexx kit for their claim of different ramp profile equals lighter weights. But I’m having to run much heavier than factory.
 
I have a 165 3” completely stock. Never had any bog issues at all. I put the ibexx kit in this weekend (clutching only). I talked to one of their guys on the phone who recommended 3-1-0-0 heel to toe. Riding 5000-8000’. His recommendation was not even close to being what it should be. It was over reviving so bad I could hardly ride it on the trail. It kept putting it in limp mode. I ended up adding way more weight. Now it’s 3-2-2-2 all 1.7g magnets. It’s way better now. I bought the ibexx kit for their claim of different ramp profile equals lighter weights. But I’m having to run much heavier than factory.
Interesting, I had mine set up at 2-1.5-0-0 as per their instructions for 8k+. Like I said, mine was only over revving 1-200 rpm from where I think it should be. I just tossed another half magnet into the first hole closest to the pin cuz it was easy to get to without taking the clutch apart, unfortunately I won’t get another ride in to test until my trip to island park next week, which I’m guessing is going to be mostly lower elevation than I’m typically riding, so hopefully it won’t turn into a trip of tinkering the whole time. Overall my sled ran pretty good with the set up, just a bit higher revs than I’m after, and I thought wot pull felt a bit softer than stock.
 
The 155 220 secondary spring and 46 helix I thought was good wasnt working at 11k ft today. Was 7900rpm going down to 7500rpm on deep pulls. Then pulled 7800 on flat meadows. Kept stopping and letting clutches cool. Eventually disconnected the throttle sensor and changed plugs (even though they looked ok) and it then it ran 8100rpm going down to 7900. Im hearing plug caps might have an issue. This is what my plugs looked like where the caps connect. Seems like odd wear. Or it could have been the sensor. Sure felt like a clutching issue, but seems like it wasnt later in the day...
 

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The 155 220 secondary spring and 46 helix I thought was good wasnt working at 11k ft today. Was 7900rpm going down to 7500rpm on deep pulls. Then pulled 7800 on flat meadows. Kept stopping and letting clutches cool.

You are lacking backshift. That spring/helix combo is way off. Helix is too steep for soft spring like that. You need secondary spring with 280 or 300 end force with helix that steep.

I would rather go to 42 helix with 140-260 or 160-260 spring.
 
Well I made the mistake of ordering an Ibexx kit and following their recommendations for 8-10k too. Literally my bone stock 600 I rode last year would destroy it climbing in 3 feet of beautiful new fluff. My boys were riding their hand me down 22 and 21 800’s I ride and I couldn’t even follow them in their tracks. I have no idea how a company doesn’t even test something before they charge that kind of money for it. This is the first time I have ever bought an entire clutch kit and the last. I will go back to my tried and true ways of tuning because the Ibexx kit is absolutely terrible. No way did they test it at all before releasing it.
 
Well I made the mistake of ordering an Ibexx kit and following their recommendations for 8-10k too. Literally my bone stock 600 I rode last year would destroy it climbing in 3 feet of beautiful new fluff. My boys were riding their hand me down 22 and 21 800’s I ride and I couldn’t even follow them in their tracks. I have no idea how a company doesn’t even test something before they charge that kind of money for it. This is the first time I have ever bought an entire clutch kit and the last. I will go back to my tried and true ways of tuning because the Ibexx kit is absolutely terrible. No way did they test it at all before releasing it.
My first time buying a kit too, was hoping to get away from spending a bunch of time dialing in my own clutching, but seems that’s not gonna be the case. I’ll probably mess around with magnet placement a bit, but if I can’t get something I like I’ll throw the stock stuff back in and grind a bit off the weights. Only complaint I had on the couple rides I got in on the stock stuff was losing a couple hundred rpm at the higher elevations I got to. Definitely don’t buy ibexx’s claims of gaining two sled lengths over stock as the top end felt a lot softer than stock, bottom end felt ok though. I raced my buddies ‘22 matryx 850 uphill a couple times and he was consistently 1-2 sled lengths ahead of me, yet I’ve seen a video of a guy running side by side with a 9r with the same clutch kit. 🤷‍♂️.
 
My first time buying a kit too, was hoping to get away from spending a bunch of time dialing in my own clutching, but seems that’s not gonna be the case. I’ll probably mess around with magnet placement a bit, but if I can’t get something I like I’ll throw the stock stuff back in and grind a bit off the weights. Only complaint I had on the couple rides I got in on the stock stuff was losing a couple hundred rpm at the higher elevations I got to. Definitely don’t buy ibexx’s claims of gaining two sled lengths over stock as the top end felt a lot softer than stock, bottom end felt ok though. I raced my buddies ‘22 matryx 850 uphill a couple times and he was consistently 1-2 sled lengths ahead of me, yet I’ve seen a video of a guy running side by side with a 9r with the same clutch kit. 🤷‍♂️.

All these hyped aftermarket clutch kits are the same (no matter the brand), steep helixes and stiff springs. They load the engine more and give this feel of "hard pull" but will lose to a stock clutching on uphill drag race. These kits are also slow on throttle, makes quick maneuvering difficult. For example many people complain that doo has too high engagment on turbos, but its there for a reason -> avoiding turbo lag. The truth is that 850Turbo R is pretty slow on throttle response under 4000rpm.

Both Polaris and Ski-Doo have their high altitude stock clutching dialed in pretty good. They have the resources to test and test until the performance is on point in average conditions. They also have pro riders for testing to verify what works for real life and what not.

I almost laughed when watched this video when the guy riding realizes that his hyped clutch kit sucks after riding a stock sled. He can ride better and manuver better on stock 165 than his own 155 with the kit.
13:00 -> 13:50


Both Doo & Pol use helixes that have end angle 40 or 42 on their non turbos and turbos for mountain deep snow riding. That is the direction you should also go with the cat clutching. Stock straight 48 helix is a non brainer and doesnt work very well unless you are riding sea level snow at the sea level altitudes like we do here. Maybe cat engineers got this idea of calibration from aftermarket companies. Its easy to go with the hype train.
 
All these hyped aftermarket clutch kits are the same (no matter the brand), steep helixes and stiff springs. They load the engine more and give this feel of "hard pull" but will lose to a stock clutching on uphill drag race. These kits are also slow on throttle, makes quick maneuvering difficult. For example many people complain that doo has too high engagment on turbos, but its there for a reason -> avoiding turbo lag. The truth is that 850Turbo R is pretty slow on throttle response under 4000rpm.

Both Polaris and Ski-Doo have their high altitude stock clutching dialed in pretty good. They have the resources to test and test until the performance is on point in average conditions. They also have pro riders for testing to verify what works for real life and what not.

I almost laughed when watched this video when the guy riding realizes that his hyped clutch kit sucks after riding a stock sled. He can ride better and manuver better on stock 165 than his own 155 with the kit.
13:00 -> 13:50


Both Doo & Pol use helixes that have end angle 40 or 42 on their non turbos and turbos for mountain deep snow riding. That is the direction you should also go with the cat clutching. Stock straight 48 helix is a non brainer and doesnt work very well unless you are riding sea level snow at the sea level altitudes like we do here. Maybe cat engineers got this idea of calibration from aftermarket companies. Its easy to go with the hype train.

The kit feels more responsive on bottom end than stock and hits top rpm quick and seems to back shift and hold it good, but that’s where I feel the benefits over stock end. Definitely doesn’t pull at wot like the stock stuff, and based on the speedo I was down at least 5 mph wot track speed from stock. I don’t remember seeing an angle stamped on the new helix, just a part number, so no idea what angle it is. They also tell you to put all the magnets at the heel of the weight leaving the two holes towards the tip empty, so in my mind that would contribute to the lack of top end pull. I’m gonna try adding or moving some magnets towards the tip and see what happens before completely throwing in the towel on the kit. I mentioned some of this on Facebook and one of the guys from Ibexx told me to message them my results, so it would seem they didn’t do a whole lot of testing with different set ups. Being a machinist myself, I also wasn’t overly impressed with the machining on the helix, so I’m going on faith that the angles are cut true.

I’ve wondered why on the old m chassis and early proclimb with cat clutches cat always ran a straight 36 helix but jumped up to a 48 when they switched to team clutches. Seems like a pretty drastic change. I just figured it had something to do with the clutch design. On my ‘20 alpha I ended up with a 45 helix and after some tinkering with springs and slp weights got something I liked, but ended up with significantly stiffer springs than stock. In the past on cat clutches I’ve always tried to clutch for as much weight with the softest springs I could pull with good results. To me that seems like it would be the most efficient for transferring power.
 
Clutching is a personal preference thing. What feels good to one person under their type of riding conditions, may totally suck to another guy. It's also about trade-offs, what you're gaining in one area, you're giving up something else in another area.
For example, back in my drag racing days I used to load the primary with as much weight as possible without the motor falling out of the power band. Great for going from point A to B as quickly as possible, but horrible backshift. It didn't matter though as hopefully I didn't need to let off the throttle and get back in it. Conversely a great back shifting set up is good for throttle response when you're constantly on-off the throttle while mountain riding. The tradeoff is this type of set-up may not load the motor as hard.

The nice thing about adjustable weights is that you can shift the mass up and down the weight profile to change the shift profile to more closely match your riding preference. For me personally what I will do is start with the clutch kit maker's recommendations then, if necessary, move the mass around a bit to suit my personal preference. For all around mixed back country riding I usually prefer to spread mass a little more evenly across the weight profile. Depending on the weight profile, helix angle and spring rates.
 
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There is nothing better about the Ibexx kit. Bottom end is soft, mid is terrible and top end is non existent. I could destroy my old 2022 800 with my 858 in every condition possible with stock clutching. I’m happy to show Ibexx and anyone that wants to see how terrible the kit performs because I have it all on video. All because the season has sucked and I thought I could short cut finding what really works. The worst part is I bought my dad a kit also so I’m out $1000. Haven’t put his kit on yet so at least I didn’t waste all of that time. So glad I didn’t buy the tune too.
 
C&s kit holds 82 to 8250 on 154. The 165 was there but in super deep snow it pulled down to 81 to 8150. Both clutched the same and work great. Both 9k+ kits.
 
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