850T Clucthing Options

[Caper11]

So if power is truly the same, secondary setting appears to be the same, im assuming but gearing appears to be the same, primary spring is the same, ramp profile is the same but overall weight is lighter by 3 grams. So does that mean that effective angle the ramp is being held in the clutch is different? Like a clicker position -2 or something?

You are not wrong in your assumptions. Is is possible that the 2021’s are going to need more pivot weight to correct RPM, as Joe mentioned.
This particular clicker flyweight profile from the 984 MY 2020.5 to the 994 2021 are the same. Joe posted info on that awhile back somewhere. The skidoo clutch calibration has always been wonky, and needs attention at times, thats where aftermarket kits come in.
Gearing may be the same as the 2020.5, a fella will have to open the case to verify what is in there, but a 165/175looks to be 21/53 and a 154 is 21/51.

 

[Dynamo^Joe]

I talk with BRP race tech and the 994 to them is called the "984Mod1" = 994. It is a 984 ramp with less side material and stamped 994. The (MY21)994 is a lighter (MY20.5)984

Re: gearing. (this is June 2020 information I have) The Turbo gearset is a HYVO and there is only one chain available, the 116p. You cannot mix chain/gear(rexnord) from the non-turbo with a HYVO turbo gearset.
The only gearing you can do on the Turbo is...
165/175 to a 20 or 22 hyvo gear.
154 can go 22, 23 top gear (but why do you want to gear faster?)
IF on the 154 you want to go lower gear, THEN you have to go to the 53 bottom gear (because you cannot go lower than 21 top gear on 21-53 w116p HYVO chain.

https://www.ibackshift.com/article/gearing-150.asp#gear2019g4

 

[NoBrakes!]

great visual explanation on the site!

 

[The Kickass One]

Guess I’ll run stock for a few rides and then switch over to DJ’s to see the difference.

 

[oler1234]

I talk with BRP race tech and the 994 to them is called the "984Mod1" = 994. It is a 984 ramp with less side material and stamped 994. The (MY21)994 is a lighter (MY20.5)984

Re: gearing. (this is June 2020 information I have) The Turbo gearset is a HYVO and there is only one chain available, the 116p. You cannot mix chain/gear(rexnord) from the non-turbo with a HYVO turbo gearset.
The only gearing you can do on the Turbo is...
165/175 to a 20 or 22 hyvo gear.
154 can go 22, 23 top gear (but why do you want to gear faster?)
IF on the 154 you want to go lower gear, THEN you have to go to the 53 bottom gear (because you cannot go lower than 21 top gear on 21-53 w116p HYVO chain.

https://www.ibackshift.com/article/gearing-150.asp#gear2019g4

joe have you had a chain case apart? is it confirmed a HYVO set? I was going to swap to a 20 top gear instead of 21/53, appears wahl bros is the only one to sell HYVO for skidoo

 

[Caper11]

joe have you had a chain case apart? is it confirmed a HYVO set? I was going to swap to a 20 top gear instead of 21/53, appears wahl bros is the only one to sell HYVO for skidoo

Its a hyvo set. There should be a warning sticker on the chaincase, the 2020.5 had one.

 

[Dynamo^Joe]

Hi. Yes i have had the case apart, cover off.
I can tell you from a phone call to me, the.......
#1 reason for Hyvo is because it is the closest to the efficiency of a belt drive as one can get.
#2 is its a little more strong.
...I say again, me being a parakeet; the reason at the top is because of the efficiency of Hyvo is closest to a belt drive.

Stock gear is 21. You can only go to a 20 top with that chain.
If you wanted to go 19-53, then you have to change the complete drive to "Rexnord/Link belt", standard OEM gears and chain.

Hyvo gears
https://venomproducts.com/index.php/parts-catalog/hy-vo-borg-warner
also in Canada, Rec Suppy in sToon distributes venom gears too.
https://catalogs.recreationsupply.co/snow-2021/

 

[Dynamo^Joe]

Here is some different information...
So, down here at 900~1450 feet. We'll go out for the day and i'll burn through my tank right to the dash alarm and then dig into the big LinQ can and be nearly on empty by the time we get out. I'll get 80~95kms and i've used all that gas.
....AND....
...so does James on his turbo 165 x 3.0, run out of his tank and dig into his LinQ can.

I guess what im saying is; dont be surprised that you Turbo owners use 2x the fuel your non-turbo buddies use "at elevations". hahaha. That's what im making for an edgeimicated guesstimate on turbo fuel consumption with my kit anyway. hahahaha

Like when i was in Revelstoke the last time, i averaged $14 bux / day. But not here at 160hp in N.Ont.

 

[maxwell]

Here is some different information...
So, down here at 900~1450 feet. We'll go out for the day and i'll burn through my tank right to the dash alarm and then dig into the big LinQ can and be nearly on empty by the time we get out. I'll get 80~95kms and i've used all that gas.
....AND....
...so does James on his turbo 165 x 3.0, run out of his tank and dig into his LinQ can.

I guess what im saying is; dont be surprised that you Turbo owners use 2x the fuel your non-turbo buddies use "at elevations". hahaha. That's what im making for an edgeimicated guesstimate on turbo fuel consumption with my kit anyway. hahahaha

Like when i was in Revelstoke the last time, i averaged $14 bux / day. But not here at 160hp in N.Ont.

i put 2000km in deep snow on the 2020.5 it uses 25-30% more fuel for sure on deep sunny days. Worth it

 

[oler1234]

Hi. Yes i have had the case apart, cover off.
I can tell you from a phone call to me, the.......
#1 reason for Hyvo is because it is the closest to the efficiency of a belt drive as one can get.
#2 is its a little more strong.
...I say again, me being a parakeet; the reason at the top is because of the efficiency of Hyvo is closest to a belt drive.

Stock gear is 21. You can only go to a 20 top with that chain.
If you wanted to go 19-53, then you have to change the complete drive to "Rexnord/Link belt", standard OEM gears and chain.

Hyvo gears
https://venomproducts.com/index.php/parts-catalog/hy-vo-borg-warner
also in Canada, Rec Suppy in sToon distributes venom gears too.
https://catalogs.recreationsupply.co/snow-2021/

thanks, yea my thought was drop 1 tooth I feel it could use it and if the chain is excessively long just get a master link and take one out to shorten it up a bit.

Minimal to zero tensioner helps efficiency even more.

not sure I buy that a belt drive is more efficient these days... lots of studies show a chain drive properly maintained is more effective. Case/point moto gp bikes use chain, these guys are at the top of there league.

 

[Dynamo^Joe]

Joe have you tried the 994 ramps versus the 984 stock in the 2020 T? Any benefits pros or cons in changing to the 994 ramps?

 

[fredw]

thanks, yea my thought was drop 1 tooth I feel it could use it and if the chain is excessively long just get a master link and take one out to shorten it up a bit.

Minimal to zero tensioner helps efficiency even more.

not sure I buy that a belt drive is more efficient these days... lots of studies show a chain drive properly maintained is more effective. Case/point moto gp bikes use chain, these guys are at the top of there league.

Biggest gain I feel with a belt drive would be on a turbo sled is a quicker spool, just the same as a lighter primary.. just take off your primary and see how much quicker your motor revs.. 1 lb of weight is equal to 7 lbs of rotational.. so a 4 lbs saving with belt drive should be a noticeable gain.. now on a long wot pull I do like the additional strength a chain offers

 

[ctd]

Biggest gain I feel with a belt drive would be on a turbo sled is a quicker spool, just the same as a lighter primary.. just take off your primary and see how much quicker your motor revs.. 1 lb of weight is equal to 7 lbs of rotational.. so a 4 lbs saving with belt drive should be a noticeable gain.. now on a long wot pull I do like the additional strength a chain offers

You have to keep in mind the closer the rotating mass is to the centerline the less dramatic the effect is. The track weight being the driveline largest factor when talking about rotating mass. I swapped the G4 track to a T3, I don't remember the difference, I've 12lbs in mind. Cannot think of a situation were the T3 track isn't better other than knowing it is 12 lbs heavier. There is good weight & bad weight thought process that enters into this as well.

Staying on topic we are trying the SLP turbo front clutch kit today in a couple of different set ups. I'm interested in the launch tube theory, I've always gone against the grain of lower engagement with turbo's & NA's. I've a multitude of reasons & more 800 E TEC experience. The launch tube follows that with adjustability rather than changing the engagement rate of the drive spring.

 

[fredw]

You have to keep in mind the closer the rotating mass is to the centerline the less dramatic the effect is. The track weight being the driveline largest factor when talking about rotating mass. I swapped the G4 track to a T3, I don't remember the difference, I've 12lbs in mind. Cannot think of a situation were the T3 track isn't better other than knowing it is 12 lbs heavier. There is good weight & bad weight thought process that enters into this as well.

Staying on topic we are trying the SLP turbo front clutch kit today in a couple of different set ups. I'm interested in the launch tube theory, I've always gone against the grain of lower engagement with turbo's & NA's. I've a multitude of reasons & more 800 E TEC experience. The launch tube follows that with adjustability rather than changing the engagement rate of the drive spring.

So your saying you swapped tracks to a heavier track and never noticed a difference? In spool or Perfomance

Track rolling resistance plays a huge roll as well and new g4 track tension is extremely tight in comparison to other tracks in the past.. now run 7 tooth drivers and tension and track resistance much less than before

 

[Cableguy]

I swapped the G4 track to a T3, I don't remember the difference, I've 12lbs in mind. Cannot think of a situation were the T3 track isn't better other than knowing it is 12 lbs heavier. There is good weight & bad weight thought process that enters into this as well.

Did the T3 axle and drivers bolt right in or did u have change drivers on the G4 axle I have been contemplating the same thing

 

[fredw]

What is making you think the g4 track is less desirable over the t3.. the few less paddles?

 

[ctd]

So your saying you swapped tracks to a heavier track and never noticed a difference? In spool or Perfomance

Cannot think of a situation were the T3 track isn't better other than knowing it is 12 lbs heavier.

Track rolling resistance plays a huge roll as well and new g4 track tension is extremely tight in comparison to other tracks in the past.. now run 7 tooth drivers and tension and track resistance much less than before

6 or 7 tooth drivers depending on if you have a 3.5 or 3.0 pitch track, it is a very small driver. It needs to run a little tighter, keep in mind the more power & faster you spin the track it will wrap around the front drivers. Upping the drivers size 1 tooth leaving the stock gearing in place is something to think about.....slightly less track tension.

 

[ctd]

I swapped the G4 track to a T3, I don't remember the difference, I've 12lbs in mind. Cannot think of a situation were the T3 track isn't better other than knowing it is 12 lbs heavier. There is good weight & bad weight thought process that enters into this as well.

Did the T3 axle and drivers bolt right in or did u have change drivers on the G4 axle I have been contemplating the same thing

T3 track is 3.0" pitch vs 3.5 for G4, not compatible. The other factor is track length.

 

[Cableguy]

ya i know there diff pitch but wondering if the t3 drive axle fits right into the gen4 chassis

 

[rknight111]

I had my Dynamo Joe clutch kit installed at Martin Motorsports west last week. Trevor and I went through the kit, he mentioned that the instructions were very good, and easy to follow. I got a service and a bumper installed on my sled so decided to have them install it rather than driving it to other places to get it installed. They did a great job, and were even texting me to ask how it was. The snow was very thin last weekend so cannot comment on how it worked in deep snow till next trip, well hopefully next trip. Firstly It was quite noticeable right from the time unloading off the deck, just touched the throttle and it was backing up, didn't hear that slight clunk when clutch is engaging. Then on take off noticed the early engagement. And as I said need a bit more snow to comment on how it worked on the hills but was very happy with the backshift going down the trails in the bush, going down steep grades through the bush it held at around 4000 RPM and 40 km/hr, that was all engine braking, the track was turning and not sliding, never had to hit brakes at all. Then coming out of Baur's down the steep grades in the cutblock it again held at around 40000 RPM and kept the speed around 40 km/hr again. On a hill going up with approximately 1' of new snow, It would holed 8000 RPM on clicker 3, on the turbo weight setting. The back shifting is very nice, have to wait for next trip to comment on the rest but will.