Polaris RMK 800 snowbike
- Thread starter Brett Kobernik
- Start date
Bingo. Now things are getting serious.
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You can bet corporate is reading ...
I had been keeping up with your project and am impressed with what you have accomplished. Nice job!
I am curious, did you ever install some track clips, or something similar, to your track for your newly designed monorail suspension? Did you experience much resistance/friction or drag with the track directly on the hyfax of the rails?
I am curious, did you ever install some track clips, or something similar, to your track for your newly designed monorail suspension? Did you experience much resistance/friction or drag with the track directly on the hyfax of the rails?
^^^Yes, I did install some track clips so as to not melt the track/hyfax. Made a clip crimper out of a bolt cutter. It worked.
Since then I purchased an Arctic Cat Power Claw 3.0x155. This is the track that is made for the single rail skid. It has special center clips with a guide that runs down the middle of the single rail. The track has amazing traction.
The machine has been unreal. It's been deep here in central Utah and the bike has been charging. Absolutely the best riding I've ever done. I lead and others can only follow my track. Doesn't matter if we're in open country or in the tight trees, I'm out in front. I have some more updates to do and will keep posting. In the meantime, here's a few clips of riding before the snow kicked back in mid Feb:
Since then I purchased an Arctic Cat Power Claw 3.0x155. This is the track that is made for the single rail skid. It has special center clips with a guide that runs down the middle of the single rail. The track has amazing traction.
The machine has been unreal. It's been deep here in central Utah and the bike has been charging. Absolutely the best riding I've ever done. I lead and others can only follow my track. Doesn't matter if we're in open country or in the tight trees, I'm out in front. I have some more updates to do and will keep posting. In the meantime, here's a few clips of riding before the snow kicked back in mid Feb:
I read through this whole thread recently, and I have to say: Bravo! I've never rode a snowbike, partly because I've never rode dirt bikes to speak of, and the idea of shifting and riding is alien to me. Also, not sure how I'd do with the lack of power. Probably not a big deal with a season like we're having, but my impression is you either have to own a full-up sled and the snowbike or resign yourself to staying home on deep days. I'm sure the manufacturers have made similar conversions, and I'd think it's just a matter of time before someone sells one. In the meantime, great effort, and I'd love to try such a thing out some day.
Bingo. That’s exactly what the hard core guys do that I know in my region.
The last month has been outstanding for riding. Things have calmed down a bit so I figured it was time to install the belt drive. I’ve been riding the Unicorn 580 while I work on the 800. I forget that the Unicorn is no slouch and I’m still always way out front of my partners. Anyway, here’s the belt drive. TKI pulleys, Gates Poly Chain GT Carbon belt, 8mm pitch, 36mm wide. These come in a wide range of lengths. DIY belt tensioner. This set up will give me the drive ratio that I couldn’t perfect with the chain sprockets. Hopefully test it Friday.
That thing seems to work really well. But I am kinda wondering what's the difference between that and let's say an updated Snow Hawk of even a Exo Sled ?
I’ll let you know after my second attempt. The first attempt didn’t go so well! One of my pulleys was too close to the housing and was rubbing a groove in the aluminum. This heat things up until the belt turned into a puddle! The thing that I didn’t notice in the first 2 miles before it crapped out was that the gearing is way better. Much peppier on the lower end of course.
Completely different geometry than either of those machines.
The snowhawk uses a narrow track. I'm using a full size 15" wide track.
The Exo Sled is heavier and wider. Too wide in my opinion. Can't say for sure because I've never ridden one but I'm pretty sure the width is going to hamper steep side hilling. I thought about trying to use the sled bulkhead but quickly dismissed that because of it's width.
I can attest the exosled is a complete failure…….
The slightest sidehill and the ski loses purchase due to the side panel hitting snow and you pitch headfirst down the hill cursing.
Absolutely zero good from that product.
I had one on my turbo 2016 Axys.
Minor set back
Big thing with the belt drives is they need to be very rigid , things like a weak back plate or a bad driveshaft will prematurely destroy them and looks like you've got that locked down.Did you get your engagement around or under 3000rpm ? Looked fairly smooth in one of your vids.
Hi Brett, spring is officially here, have you had any hard snow yet to test the alpha? I was thinking about how the side panel clearance might be a tad less with the alpha in hard snow as the chassis pivots from the middle instead of the edge. But the 3"track probably gives you back the lift you lost from pivoting on the edge.
Also going back to page 1 of this build shows how you gained what looks like at least 2 inches of clutch clearance by moving the motor to the side. This is the biggest difference from an exo sled.
Also going back to page 1 of this build shows how you gained what looks like at least 2 inches of clutch clearance by moving the motor to the side. This is the biggest difference from an exo sled.
Good info @Sheetmetalfab and good for you giving that system a fair shake. That sounds like what I kinda suspected.
Thanks for the backing plate thoughts. I've been thinking that I'll need to fabricate a sturdier backing plate. I'm not quite sure where the engagement is but it is smooth. I haven't screwed with the clutch a whole lot yet because I want to get that belt and gearing dialed first. I'm going to put a Powerbloc clutch on next season.Minor set back
Did you get your engagement around or under 3000rpm ? Looked fairly smooth in one of your vids.
I haven't tested it on steep firm sidehilling yet. I was out on some of that stuff the other day but was on my 580 after I turned the belt on the 800 into a wad of melted rubber. I'll get onto some steeper firm stuff this week. And yeah, you're correct about mounting the engine off to one side. It is also a few inches (maybe 3 or more?) higher than where it is mounted in the sled bulkhead. Both those things gave me the clearance needed to make this thing work. Side note, it was great to meet you in person and get some riding in. I really appreciated those bikes you guys were on. Well done.
If you can find a powerbloc 50 , save you some coin , we don't have enough power to hurt the 50 . the 80's are just reinforced, same clutch and you could turn it into an 80 with the right tooling otherwise locktite is a must on the main nut you won't have any issues.
One of the guys put one on his M8000 before it ate the stock one, he's happy.
Only disclaimer is if you have an engine with a known crap crank don't do it. These clutches do not hold the engine back, throttle response is instant, your long overdue
otherwise locktite is a must on the main nut you won't have any issues.One of the guys put one on his M8000 before it ate the stock one, he's happy.
Only disclaimer is if you have an engine with a known crap crank don't do it. These clutches do not hold the engine back, throttle response is instant, your long overdue
Did you contact us to be sure you have the right setting to take advantage of EXO Sled? Many of our customers are more than happy to ride EXO Sled. Most of the time, minor tweaks make a huge difference.
Yeah @Sheetmetalfab were you using the "narrower bulkhead setting"?
Sorry @EXO Sled I can't help being a sarcastic asshole sometimes.
I do applaud your product and outside of the box thinking. Probably works great for certain people in certain terrain/snow conditions. I'd like to try one sometime if you guys ever end up in central Utah.
