How many have changed gearing on an n/a viper/7000?

[Studroes144]

My turbo pulled over 112 last season with stock gearing, stock clutches, ulmer clutch kit, OSP adjuster and 8DN belt. A NA sled won't get there but the drive train is capable of it.

With aftermarket clutch parts and the 8dn belt it's definitely possible to pull some overdrive to get past 105, and of course the biggest factor being hp, 8dn belt gets a bit more speed because it's longer and more than likely the helix in the Ulmer kit is setup so that the secondary will be able to get full shift. Not sure what percentage of overdrive just a helix can attain, but if you figure roughly 5% which I'm sure is in the ballpark then you're looking at right in the 112 range, it takes a lot of power to pull any overdrive though. From some of the speeds being posted on snow it seems like the sleds with full bolt on mods and stock gearing are getting only a small percent of overdrive, but I believe they're getting to that 100-105 mph mark fairly quick when conditions are right and then a slow crawl from there.

 

[Studroes144]

Here is what I had and what I have done so far.... Naturally aspirated, stock gearing on XTX worked great for asphalt and trail/off-trail. Top speed on asphalt was 113-115mph. Top speed on trail was 108mph with a glimpse of 110mph. ***I am machined for overdrive***

Wanted more speed cause I was running out of gear, so I bought a 22 tooth top gear from someone, but it was an Artic cat 22 tooth. I found a 40 tooth Arctic Cat bottom gear (Same exact gear that your reverse uses) for $20 on good ol Ebay, purchased an Arctic Cat chain and ran that the last few months on asphalt. Top speed was 112-114mph but my times were quicker. Haven't tried is on trail yet but hoping for that almighty 115mph with all my NA mods now.

So that should be a good example that taller gearing does not hurt the lo-mid range power on these sleds, if anything it'll help it. On this 7000 it's hard to explain how it acts, if anyone was to drive it they'd know exactly what I mean. From a stand still it's a rocket out to a certain point, I'd say 60-70 mph, as fast as most anything I've ridden aside from a turbo, after that it still maintains rpm good, doesn't over rev at all, doesn't under rev at all it just stays revved nice and smooth but seems to lose the grunt. One of my last dodge trucks I had had very tall gearing, lacked some snap down low but once it got into the power and pulling that taller gearing it just pulled and pulled, my new truck now I got the lowest gearing I could get, amazing power right from idle, good smooth acceleration, but at higher speeds the gears are so close together that it's just rolling through the gears rather than using the power to really make it pull. Not sure if that makes sens but this 7000 feels the exact same way, I think it's going to have just as quick acceleration and hopefully 10 more mph on the big end with new gearing. I'm gearing roughly 10% over the top speed I want to have, on a torque engine I think it's gonna have good results.

 

[TD Max]

The RTX LE shares the same gearing as the Cats. 21-49. What I did just to be thrifty was purchase a 24T upper and the appropriate 92P? chain leaving the lower sprocket as is. This puts me just a hair over the std Viper gearing. Only time will tell.

 

[Studroes144]

The RTX LE shares the same gearing as the Cats. 21-49. What I did just to be thrifty was purchase a 24T upper and the appropriate 92P? chain leaving the lower sprocket as is. This puts me just a hair over the std Viper gearing. Only time will tell.

Considered that but I want an even lower ratio and there is such an abundance of 21/41 gears and chains from the Arctic cat side.

 

[randh]

Hi guys i just want to say this site rocks! Been reading here for awhile. Just joined as i am very interested in this tread and out come. I have a 2014 zr 7000 sno pro limited its hard to find a site that even talks about the cat like this site dose without putting them down when they are the same sled. That being said my buddy with a 2014 rtx se and i have raced and found that the cat gets the hole shot every time but then the sleds are pretty much side by side all the way to flat out full throttle on a very long lake with the cat edging by just a hair even with rider switch. Top speed on both is about 102 in perfect conditions other wise i would have to say sleds are a good all around 95 mph sled. I am new to this but want to change gears to the 21/41 also how do you know what gears fit on shafts and length of chain needed is a cat gear a cat gear and thats what fits all cats? I do alot of work on cars and dirt bikes but just don't know sleds "YET'. LET IT SNOW!!!!!!

 

[NOS-PRO]

Welcome randh

You will find a whole lot of info you are looking for and if you can't find it....just ask

One thing you will not see here is brand bashing like other sites, that's why all the guys and gals here are helpful and want everyones sled to run their best.

 

[shagman]

Hi guys i just want to say this site rocks! Been reading here for awhile. Just joined as i am very interested in this tread and out come. I have a 2014 zr 7000 sno pro limited its hard to find a site that even talks about the cat like this site dose without putting them down when they are the same sled. That being said my buddy with a 2014 rtx se and i have raced and found that the cat gets the hole shot every time but then the sleds are pretty much side by side all the way to flat out full throttle on a very long lake with the cat edging by just a hair even with rider switch. Top speed on both is about 102 in perfect conditions other wise i would have to say sleds are a good all around 95 mph sled. I am new to this but want to change gears to the 21/41 also how do you know what gears fit on shafts and length of chain needed is a cat gear a cat gear and thats what fits all cats? I do alot of work on cars and dirt bikes but just don't know sleds "YET'. LET IT SNOW!!!!!!

21/41 uses a 86p chain.


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[randh]

So will a set from a XF 1100T work? Part #1702-336

 

[shagman]

so will a set from a XF 1100T work?

Yes I think so. But check parts breakdown to make sure. Im running a drive axel out of a cat and it's the my viper.


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[Studroes144]

Hi guys i just want to say this site rocks! Been reading here for awhile. Just joined as i am very interested in this tread and out come. I have a 2014 zr 7000 sno pro limited its hard to find a site that even talks about the cat like this site dose without putting them down when they are the same sled. That being said my buddy with a 2014 rtx se and i have raced and found that the cat gets the hole shot every time but then the sleds are pretty much side by side all the way to flat out full throttle on a very long lake with the cat edging by just a hair even with rider switch. Top speed on both is about 102 in perfect conditions other wise i would have to say sleds are a good all around 95 mph sled. I am new to this but want to change gears to the 21/41 also how do you know what gears fit on shafts and length of chain needed is a cat gear a cat gear and thats what fits all cats? I do alot of work on cars and dirt bikes but just don't know sleds "YET'. LET IT SNOW!!!!!!

Now u got me wondering if the short track zr comes with taller gearing than the 21/49 that's in the xf, this xf7000 is dead in its tracks at shortly over 90 but pulls great the whole way there and is using pretty much the whole surface of the clutch sheaves, very comparable to the stock yammi clutches at full shift without machining.

 

[Jim R]

Running the ZR I am jealous of the Yami clutches. I installed the SSI full clutch kit thinking it will improve the AC clutch quality. Time will tell.

 

[Studroes144]

Running the ZR I am jealous of the Yami clutches. I installed the SSI full clutch kit thinking it will improve the AC clutch quality. Time will tell.

Cat clutches won't have the longevity, but I will say that they work extremely smooth, not gonna start a clutch comparison, that's been beat to death, but from the experience I've had riding several different vipers and a couple cat 7000's, the cat clutches are more smooth. But the viper has been faster in all the situations I've seen which all leads back to clutching. Cat clutches do put the power down very fast tho, 7000's always came out in front of the viper for the first couple hundred feet, but the 2 cats we've ridden with were both xf' with lower gearing.

 

[randh]

The xf7000 with the 137 and the zr
129 both run 21/49 in 2014. Don't know if they changed in other years? That's the case I should only need bottom gear and chain to go 21/41 right?

 

[NOS-PRO]

Only thing I would be skeptical of is if it's a CAT chain or Yamaha chain. There is a dfference if you look at the plates of the chain.

The XF1100 I think would be a cat chain and gears....that is why when I ordered my 22 tooth top gear, an Arctic Cat gear was sent to me....this was because the Viper was new and the guy figured they were the same.

 

[Ryno]

Now u got me wondering if the short track zr comes with taller gearing than the 21/49 that's in the xf, this xf7000 is dead in its tracks at shortly over 90 but pulls great the whole way there and is using pretty much the whole surface of the clutch sheaves, very comparable to the stock yammi clutches at full shift without machining.

Short track gearing is the same 21/49. I am new as well and follow you guys religiously. Awesome info. In my short 1 month of owning my sled I am convinced the gearing is way too low. I will be replacing as a spring project along with a few bolt on! Hurry up and get this figured out so I have an easier time when I do it!!! As I said you guys are great!