I regeared my 136 1.3 cobra to 1.86. Loved it. Stock clutching. Speedo requires recalibration by dealer…

 

23/40 works good on my 129". Came with storm and the gear change actually make the speedo closer to GPS than it was before. Running cobra track on it now as the storm didn't hold up. Not sure that a heavy person could get away with this gearing on a 1.5" track. I'm pretty light.

 

Are you looking to make it quicker or add top speed? Personally I wouldn't go taller which sounds like what you are saying.

 

Gearing a 1.5 like a 1.25(1.3). Isnt going to work well. I’ve tried gearing up the bigger tracked sleds with about 0 gain in mph. But increased clutch heat and probably not as quick. My 1.6 cobra tracked 136 will run over a true hundred. 102-105. And it does it quickly. If you’re looking for more mph than that I would change tracks adjust gearing for that and clutch properly. A few years back I gained 14mph by going from a 1.75 to a 1.3. With no other changes than gearing for the lower lug.

 

Yeah it's a pretty big difference in gearing. I got the storm for the track, plus the gearing as I don't need to go much over 100mph.

Like others have said, I think a gear change and track with lower lug height will get you more top speed. On world record snowmobile jump attempts they had to ditch the snocross lug track and go with a smaller lug track to get the top speed they needed.

Do these sleds need to have the speedo adjusted by the dealer to read the correct mph still? I know my Pro R did.

 

Yeah it's a pretty big difference in gearing. I got the storm for the track, plus the gearing as I don't need to go much over 100mph.

Like others have said, I think a gear change and track with lower lug height will get you more top speed. On world record snowmobile jump attempts they had to ditch the snocross lug track and go with a smaller lug track to get the top speed they needed.

Do these sleds need to have the speedo adjusted by the dealer to read the correct mph still? I know my Pro R did.

Yes. With digital wrench or an aftermarket equivalent. The best way to do it if you have access is run the sled on gps and pick a speed of your choice. Then play with the programmed gear ration until the speedo most closely matches. Real speed. You can actually get closer to actual doing this even if it’s not the real gear ration in chaincase. But most don’t have the access to keep Messi g with it and just use Polaris gear numbers to get them close.

 

When I geared my Axys Switchback for out west last spring I was going 10mph faster than one of the guys who didn’t, so right at 20%. His speedo showed 50 when mine showed 60. This was a big swing going from flat land stock 22/37 to 20/39. For the fun of it I plan on running those gears for the first trip this year and see how it runs. I know I’ll lose top speed for sure but I don’t care about that.

 

You have to clarify what you’re looking for as in more bottom end and mid range?
More top end?
Your stock gearing is 1:86 ratio, 41-22 with 70 pitch chain.
This is an all Around good ratio.

Polaris typically gears their sleds taller and the clutches don’t fully shift out.

 

What rpm is your engine running at when full throttle?

What is the weight of rider and gear?

Are you looking for more top end speed?

Your current stock gearing (22/41-70 1.86) should give pretty good acceleration up to at least 85 mph or so.
Track speed of around 96 mph @ 8,250 engine rpm, without clutch overdrive.

 

Sounds pretty close. They can run that 83-85 in 500 ft with lil to no magic.in snow. and then continue to gain until about 1000 ft where they are pretty much out of smoke. But pretty good Into OD. running at 8150. Over 100.

 

to get more power to the ground I think you may have to look into clutching before doing gearing

 

Like others stated can you be alittle more detailed where the performance is lacking that your looking for?

Have you looked at clutching? Have you changed anything? Checked belt deflection? Is it shifting out and not binding. Just a couple easy things to rule out before a gear change.

 

Like the 1 guy said, pulls good to 80 and after that it’s pretty lame.
Rpms are always spot on around 8200 .
IMO I was quite surprised at the large gearing difference between the 2 stock tracks, that’s why I think I’d like try to gear it up slightly to 22/38.

Not sure if a 38 gear is available with the stock chain I have.

 

Like the 1 guy said, pulls good to 80 and after that it’s pretty lame.
Rpms are always spot on around 8200 .
IMO I was quite surprised at the large gearing difference between the 2 stock tracks, that’s why I think I’d like try to gear it up slightly to 22/38.

Not sure if a 38 gear is available with the stock chain I have.

Weight of Driver and gear?

22/38 will have WAY too much slack for 70 pitch chain in a Matryx flatland chassis.

 

You’d need a 68 chain

 

You need to find out why it’s not pulling or if you just feel by the ass dyno it’s not pulling. it’s not the gearing. If at some point you can tell me how fast it’s going in 500ft then 660 then 1000 I can tell ya if it’s pulling or if it’s not. I have stock gearing for a 22 850 with 1.6 track and it pulls past 1:1 mph and pretty good into OD.

 

Yep my 2020 850 assault 1.6 had no problem running to 108 on speedo. If it flat after 80 I'd be looking at drive line friction, clutch alignment, belt condition, clutch roller wear, binding secondary etc.

 

Yep. The clutches are load sensitive. If the load is more than the hp available, upshifting will slow down/stop. Engine and clutch alignment is typically way off on new sleds. You should reduce the excess forward twist of the engine to no more than .020". Then, float the 2ndy about .090-.120" INWARD from the location of the best self-aligned position at launch. Find this position by raising the track off the ground and spinning the engine and clutches at just above engagement. Make sure deflection is set correctly. Shim the retaining bolt to maintain this location. Then allow INWARD float from there. This frees up hp to the track. You'll be amazed at the performance gain.

 

The storm is a heavy track. Probably why the big difference in gearing vs the cobra

 

Camso specs show the 137 Storm 1.50 at 39.6 lb.
--- and they show the 137 Cobra 1.352 at 39 lb.
0.6 lb is 1.5% less weight.

 

it's your clutching. the drive spring is wrong and the driven 155/222 spring is the absolute worst spring there is. a good clutch kit will fix all your issue's. i have a 2019 850xc indy 129 with a storm track. do not go to a 22/38 gearing. it won't pull unless on glare ice or very hard packed snow. my 850 stock gearing does 103-105 and pulls all the way there.

 

Ok, so it sounds like maybe a “clutch kit” is possibly what I’m looking for.

Primarily I just cruise on groomed trails, and I’m 190 lbs.

I guess I’ll research some clutch kits.

 

Ok, so it sounds like maybe a “clutch kit” is possibly what I’m looking for.

Primarily I just cruise on groomed trails, and I’m 190 lbs.

I guess I’ll research some clutch kits.

There's some good reads on clutching function, what effect of each component has, optimizing the function of the clutching to your riding style. There's really is no one setup that fits each individual riding style. Learning the clutching and component function helps what your looking for.

This is an old book but gives very good insight to clutch tuning

 

Im happy with Ricks kit. 603-662-7370

 

Your 1.5 track will never have anywher near the speed that a 1.35 has no matter what you do.