Changed my track to a 1.75 backcountry,changed stock 23-39 gears to 20-42.Left clutching stock,now with the 20-42 gears seems a little to slow.Anyone have any other ideas on gearing to try ?
switchback assault 1.75
- Thread starter shift08
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I have the same setup on my SWA and happy with it. I do not ride trail much so do not need high speed capability.
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Carlos Randolph
Active member
Gears
I ran a 22tooth upper with the 39 lower on mine with a 2" track. worked just fine, and pulled 8100-8250rpms all day. it would get the belt/clutches warmish if you were running deep snow alot, but I chose to take that trade off as to beable to run down the lake/s in the 100ish range. I just changed back to the 1.35 track and stock gearing, as I ripped off a ton of lugs on a hill climb that had a hidden rock/s. The sled is now back in lame'ola mode. Way more fun with the tall lug on there. I will get another tall lug track next year.
20/42 will be slow on the trail (2.1ratio), and might over rev in that type situation (trail/s) unless you added some weight to the primary? Just not working/loading the motor when it's geared down that much. That set up would probably be about right gearing wise at elevation, in deep powder. If it were me, I would order a 22t from TEAM for the top gear, and start there, running the stock 39 bottom (1.77 ratio). Also could try the stock 23t, with your 42t bottom (1.82 ratio) If the chain will fit. Stock 23/39 is (1.69 ratio).
I ran a 22tooth upper with the 39 lower on mine with a 2" track. worked just fine, and pulled 8100-8250rpms all day. it would get the belt/clutches warmish if you were running deep snow alot, but I chose to take that trade off as to beable to run down the lake/s in the 100ish range. I just changed back to the 1.35 track and stock gearing, as I ripped off a ton of lugs on a hill climb that had a hidden rock/s. The sled is now back in lame'ola mode. Way more fun with the tall lug on there. I will get another tall lug track next year.
20/42 will be slow on the trail (2.1ratio), and might over rev in that type situation (trail/s) unless you added some weight to the primary? Just not working/loading the motor when it's geared down that much. That set up would probably be about right gearing wise at elevation, in deep powder. If it were me, I would order a 22t from TEAM for the top gear, and start there, running the stock 39 bottom (1.77 ratio). Also could try the stock 23t, with your 42t bottom (1.82 ratio) If the chain will fit. Stock 23/39 is (1.69 ratio).
Thanks Carlos,lots of good info.Do you think a 22 top and 39 bottom will still pull the sled good on the bottom end ? I weigh bout 250 geared up.
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Carlos Randolph
Active member
PULL?
Depends upon what your looking 4? The 22t on top helps it get up outa the hole better 4 sure, and generally all around pull better, but drops about 5-7mph real world top speed compared to stock 23/39. It will also not have such excessively high RPM's running down the trail at say 35-55mph if your running 20/42. With the 20/42 seems like the are stuck in the wrong gear (in car terms) and you almost better off running in deeper snow just to make the thing work right. The 22t is kinda a "tweener" set up, as it does a little of both "ok" but neither perfect. Try it, as the TEAM 22t gear from Dennis KIRK was like $35, or give one of the other combo's a try that you already own. I personally would give the 23t stock combined with the 42t bottom you are currently running a shot if the chain will fit. You already have the parts, and swaping gears is easy. FYI I also go around 250lbs in my gear.
Depends upon what your looking 4? The 22t on top helps it get up outa the hole better 4 sure, and generally all around pull better, but drops about 5-7mph real world top speed compared to stock 23/39. It will also not have such excessively high RPM's running down the trail at say 35-55mph if your running 20/42. With the 20/42 seems like the are stuck in the wrong gear (in car terms) and you almost better off running in deeper snow just to make the thing work right. The 22t is kinda a "tweener" set up, as it does a little of both "ok" but neither perfect. Try it, as the TEAM 22t gear from Dennis KIRK was like $35, or give one of the other combo's a try that you already own. I personally would give the 23t stock combined with the 42t bottom you are currently running a shot if the chain will fit. You already have the parts, and swaping gears is easy. FYI I also go around 250lbs in my gear.
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So i ended up talking to a local dealer who has been doing some messing around with gearing and clutching. I ended up getting a 21-40 gear setup which should be in the middle of what i had and have. Also he mentioned putting 10-68 weights in,trying that and if need be grind them down to 67.Not sure about weights as i have never messed with them, any thoughts ?
You'd be amazed what a little clutching and gearing will do for any sled
What altitude are you at?
Don't be afraid to play with springs and weights, learning to clutch will get you better results than any gearing ever will. This motor makes most HP and torque at 8250 rpm. If you can set your clutching to that you will be laughing. My 11 assault I ran the Slp blue/pink primary spring and 68g weights. This was set for about 2000 foot elevation. Was just a tad heavy but was close enough without grinding weights. Sled would rev to 8200 and when loaded pull about 8000. I didn't think the 100 rpm or so that i needed to tune for was worth grinding weights. Worked just fine for my liking. Was also running the 1.75" backcountry track
What altitude are you at?
Don't be afraid to play with springs and weights, learning to clutch will get you better results than any gearing ever will. This motor makes most HP and torque at 8250 rpm. If you can set your clutching to that you will be laughing. My 11 assault I ran the Slp blue/pink primary spring and 68g weights. This was set for about 2000 foot elevation. Was just a tad heavy but was close enough without grinding weights. Sled would rev to 8200 and when loaded pull about 8000. I didn't think the 100 rpm or so that i needed to tune for was worth grinding weights. Worked just fine for my liking. Was also running the 1.75" backcountry track
I am in wisconsin so my elavation is going to be set for 2,000 feet or less. I hope buy changing the gears and messing with weights i can get it dialed in so it pulls good on the trail and also works good off trail so im not trenching or burning belt at slower speeds.
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Carlos Randolph
Active member
If it will pull the heavy weight with the new gear set to 8200ish it will be great. Interested to hear how it turns out? I like to tinker with these things, while trying to not do to much that could mess with the warranty, or cost me an arm and a leg. Gearing up and down fits the bill, and can change how the sled works dramaticly. I am always insearch of the perfect setup for me, and also like to change the sled to better suit the snow conditions. For example I like to run steeper gears in the heavy/sticky March/april spring oatmeal snow that is coming. It is also relatively cheap, regreatbly I am a former doo guy, and don't have a stock pile of weights/springs and gears for the Polaris to just mess around with, like I had amassed over the years for my doo's.
I have same track. I have 21/41 which is 1.95 ratio and you can use stock chain. It's perfect all around for what i do. I felt the 20/42 was a bit zingy for my conditions/area. I do mostly boondocking/ freeriding. I only go on trails once in a while or to get where I am going. Belt never smells even at low rpm in deep snow. Stock clutching and 800 - 1700 feet.
Running the Welch hill climb?
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danduvall
Well-known member
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Carlos Randolph
Active member
No not running welch, I did this on a hill up on Kabetogama......I think
well i ended up putting in 21-40 gears but left the stock weights in.Seems to pull really good on trail,good in the ditch but havent had it in real deep powder yet( its getting thin out there) All in all real happy with this gearing and 1.75 track. I put a set of simmons cooling fins on my skis and seem to help with cooling but still hit 141 on the temp guage once yesterday on the trail.For now i think i will leave the clutching stock . What does everyone use for scratchers ? Cable ones or the wire ones ? Was looking at the duraflex cable ones,not sure.
I'm quite surprised you are seeing higher temps. My assault never hit more than 127. And that was a lot of trail riding on trips with my dad.
I don't have any experiences with the cable scratchers. Just seen them on others sleds. Watching them they don't seem to throw as much snow. Likely not as much down force. But they also don't bend. Kind of a fifty fifty toss up
I knows spring style scratchers on my rmk are hooped tho
I don't have any experiences with the cable scratchers. Just seen them on others sleds. Watching them they don't seem to throw as much snow. Likely not as much down force. But they also don't bend. Kind of a fifty fifty toss up
I knows spring style scratchers on my rmk are hooped tho
