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heavy weight light springs theory ???

shwantz34

shwantz34

Member
Messages
69
Location
Ste-Brigitte -De-Laval
Country
Canada
Years Snowmobiling
2019
Snowmobile
Polaris Indy 850 XC 129
hi,

i'm new here and find some pretty ineresting information,
One of them is to use heavy weight in the primary with light springs,
i understand the benefit of it, (no loss energy against spring tension),
but something is missing in my mind, if you load ramp weight, you will loose
rpm, if you go lighter on springs you will loose rpm ???
how can i do that and attain my target rpm ?

Please let me know i'm confuse.
 
This is the way I tune my sleds and they run very strong. But that's not saying that way is the only way to achieve max RPMS.
I run 11-66s in my Stock motor INDY with a 140/340 Spring.
Now in my Assault I am Running Dalton QAP3s with a 120/320.
I will be testing the the 11-66s with a 120/340 against the current setup over the weekend on the timer for 660'.
They way I always learned was it was
Better to load the motor hard for max accelerarion and performance. So far it's worked.
On the finish of the primary say a 310 vs a 320, the RPMS will increase by about 100. So this should allow a little more clutch weight.
 
ok Right now i run 10-70 with a 160/310 Polaris almond /Red primary
the low , low mid and mid are awsome, but it seems to fade on high, doesn't
feel like it is pulling as it can. my top rpm is around 8250/8300.
my max hp on 17 is suppose to be a 8400. i have try some spring with higher
finish, but it doesn t work, stay same rpm. i does not have a spring with the same
primary tension for my test the only available was a 190/335. it destroy my awsome mid
and does not rev higher on top. Loading the ramp definitely seems to make a great change
in the right direction, i feel my sled pulling, not just reving.

what if i go with lighter weight , lighter springs compare to heavy weight heavy spring to achieve
the same target rpm, will it shift as efficiently ?
 
Heavier weights and the lightest springs goes way back to racing Polaris and cats in the 80's and 90's.

Heavier weights =quicker upshift.
Less spring tension =less friction.

This equals fast .

Now you take that theory and back it off a little for fast trail riding. You don't wanna use a drag race set up for trail as it has no back shift. It's made to up shift hard and fast.

This is were I base my set ups but back it off a little for back shift and trail riding with some racing

So, use the heaviest weight you can and the lightest springs without suffering in rpm for fast trail (up shift and back shift)
 
tanks for the reply Brock.
so can you help me to finish my set up, right now i begin to have a very good set up, but
Im missing some top end. its good but not as good as i think it can be.
the low and low mid, mid is awsome, mid top and top can be a bit better i think

I'm 175lbs, ride very agressive trail, and we have all kind of conditon, slow curvy , brake & shoot stuff , bit of mountain.
lot of fast open spot, so i need a lot of back shift, a lot of snap and scorching pull from 0 to top :) is it possible.

So this is my actual best set up
Gearing stock XCR 22/37 = 1.68 plus XCR are 2.52 so i think i'm realy near the 1.74 you recomand

10-70 weight
165/310 polaris Almond red
stock Helix 58/44 36
stock spring Blue/Black 123-203 73

after reading a lot of your post i whant to try
10-70
120/310
50/44 full helix
and 140/220 secondary problem is 140/220 is b/o, so i'll try 140/240

do you think its something that will work ?
any other recommandation ?
 
Get adjustable weights and be done with it as u can change for warmer weather and heavy snow. Best bang for ur buck. Everything else don't look to bad .
 
Brock said:
Get adjustable weights and be done with it as u can change for warmer weather and heavy snow. Best bang for ur buck. Everything else don't look to bad .
Click to expand...
Excellent,
thank you very much , i just receive and install my new cutler ramp but....
i find that my jack shaft bearing is destroy....

now if somebody can let me know how i can remove the chain case cover
i'll be good to replace my bearing and continue set up
 
IMAG1282.jpg
IMAG1283.jpg
IMAG1284.jpg
 
Pierre Poulin said:
I just came back from my testing ride.............. now i understand :) wowwww
Click to expand...

Well tell us all about it!!

I just came back from another test ride and dropped my weights down from 10-70s to 10-68s and now i am hitting 8200 right of the start and holding there until i run out of real estate. so now i have 10-68s, 120/310 black , 48/44 full with the stock blue/black spring for now with the 1.74 ratio....pulls awesome now..feels like how it should.

Thanks guys for all of the help
 
ogrant said:
Well tell us all about it!!

I just came back from another test ride and dropped my weights down from 10-70s to 10-68s and now i am hitting 8200 right of the start and holding there until i run out of real estate. so now i have 10-68s, 120/310 black , 48/44 full with the stock blue/black spring for now with the 1.74 ratio....pulls awesome now..feels like how it should.

Thanks guys for all of the help
Click to expand...
Just change your secondary spring only to a 140/220 bud. Little better back shift for you
 
Brock said:
Just change your secondary spring only to a 140/220 bud. Little better back shift for you
Click to expand...
i have 140/200...just doing one thing at a time so i have a handle of what is effecting what and its going in next. orps was telling me the 140/220 was back ordered until 2019...i have to source one out
 
Here we go..

So i have applied the complete recommandation that Brock post, and it completely transform my sled.
Now i have instant power every where on tap. Awesome back shift, great effective power , it made my
XCR the perfect trail weapon. At first it doesn't feel as potent in the mid as my last best set up, wich was
10-70 165-310 almond red Polaris primary spring, stock helix and stock driven spring, gearing original
XCR 22/37=1.68 but the drver on XCR are 9t 2.52, so final is about 3% longer gearing compare to
what Brock recomand. this set up gives awsome low, low mid accélération , it was pulling power wheely
everywhere, but was a bit flat on top, to climb a mountain its the perfect set up. to resume it was a grest feeling
set up (seat of the pantS) but maybe not so effective. My last test whit this set up was in great condition pretty
hard surfaces, -10 C .

Now the set up of my new Guru ( Brock)

My final setting is:
ramp : Cutler IT weight. total 73.63 G, very important to place the weight at the same place they are very sensitive and reactive to tip or hell placement. So my set up is : stock ramp 65G+ 1.98g in the tip+4.15 middle+2.5 heel

Primary spring: Venom 120/310
Helix : Venom 50/44 full
Secondary Spring 140/240 (140/220 was back order and 140/200 was in my mind too soft to atteins my 8400rpm target 2017 max hp are 200rpm higher).

Whit that set up, my sled is completely transform. it will hit beethween 8350/8450 ,and stay there, any timeask for power, this is right there, instant response.Like i said at first it doesn't seems as good as my other set up, but its only because condition was not as good (less traction) it is way faster
than it was. Its what i will call deceptively fast, its the first time since i flash my AC 1100 turbo (vipec 270hp) that came too hot in corner, the setup that Brock put together is Very very effective, it is a perfect fit for what an XCR is made for : A cross country Racer. I can't find the right word to describe how good and effective the set up that Brock have put together, and graciously share whit us ( like you can see my English is not the best).

an exemple yesterday condition was windy and snowy (side wind 3 to 4 inch fresh snow) and it was still pulling is rpm everywhere.
in those condition normally i loose around 200/300 rpm and my sled was not very snappy.

I can not thank's Enought Brock to share is knowledge with us, its the biggest gist i receive since long.

Thank you very much Brock

last note:
1- I'll try when available the 140/220 and the 140/200 secondary i think in certain condition it will pull it easy
2- I'll try original 10/70 or 10/72 to see if it change something
3- If it was to do again i will have try the Cutler TM (more agressive profile) i'm sure it will be a great combination
 
nice report Pierre. don't worry about your english, it's fine. I just read it with a french accent and it makes perfect sense to me.:Tsr
 
Sadly your English is better than a lot of Americans
 
I have an SSI blue 145/225 secondary spring in my wife's 600 ProS and it works very good. Gas mileage is better, rpms are around 8250 max and it hit 104mph on the lake with my brothers 220lb ass on it! LOL

When I get a day to test, I'm going to put that spring in my 800 and see how it pulls...
 
Pierre Poulin said:
Here we go..

So i have applied the complete recommandation that Brock post, and it completely transform my sled.
Now i have instant power every where on tap. Awesome back shift, great effective power , it made my
XCR the perfect trail weapon. At first it doesn't feel as potent in the mid as my last best set up, wich was
10-70 165-310 almond red Polaris primary spring, stock helix and stock driven spring, gearing original
XCR 22/37=1.68 but the drver on XCR are 9t 2.52, so final is about 3% longer gearing compare to
what Brock recomand. this set up gives awsome low, low mid accélération , it was pulling power wheely
everywhere, but was a bit flat on top, to climb a mountain its the perfect set up. to resume it was a grest feeling
set up (seat of the pantS) but maybe not so effective. My last test whit this set up was in great condition pretty
hard surfaces, -10 C .

Now the set up of my new Guru ( Brock)

My final setting is:
ramp : Cutler IT weight. total 73.63 G, very important to place the weight at the same place they are very sensitive and reactive to tip or hell placement. So my set up is : stock ramp 65G+ 1.98g in the tip+4.15 middle+2.5 heel

Primary spring: Venom 120/310
Helix : Venom 50/44 full
Secondary Spring 140/240 (140/220 was back order and 140/200 was in my mind too soft to atteins my 8400rpm target 2017 max hp are 200rpm higher).

Whit that set up, my sled is completely transform. it will hit beethween 8350/8450 ,and stay there, any timeask for power, this is right there, instant response.Like i said at first it doesn't seems as good as my other set up, but its only because condition was not as good (less traction) it is way faster
than it was. Its what i will call deceptively fast, its the first time since i flash my AC 1100 turbo (vipec 270hp) that came too hot in corner, the setup that Brock put together is Very very effective, it is a perfect fit for what an XCR is made for : A cross country Racer. I can't find the right word to describe how good and effective the set up that Brock have put together, and graciously share whit us ( like you can see my English is not the best).

an exemple yesterday condition was windy and snowy (side wind 3 to 4 inch fresh snow) and it was still pulling is rpm everywhere.
in those condition normally i loose around 200/300 rpm and my sled was not very snappy.

I can not thank's Enought Brock to share is knowledge with us, its the biggest gist i receive since long.

Thank you very much Brock

last note:
1- I'll try when available the 140/220 and the 140/200 secondary i think in certain condition it will pull it easy
2- I'll try original 10/70 or 10/72 to see if it change something
3- If it was to do again i will have try the Cutler TM (more agressive profile) i'm sure it will be a great combination
Click to expand...
you wont be able to pull the weight you are pulling if you put a 140-220 secondary spring in it..thats a lot of mid weight, but your secondary is helping you right now because of the shift rate on that spring your secondary is shifting slower allowing ur higher rpm..dont mess with it if you like it where it is..
 
Pierre Poulin said:
Here we go..

So i have applied the complete recommandation that Brock post, and it completely transform my sled.
Now i have instant power every where on tap. Awesome back shift, great effective power , it made my
XCR the perfect trail weapon. At first it doesn't feel as potent in the mid as my last best set up, wich was
10-70 165-310 almond red Polaris primary spring, stock helix and stock driven spring, gearing original
XCR 22/37=1.68 but the drver on XCR are 9t 2.52, so final is about 3% longer gearing compare to
what Brock recomand. this set up gives awsome low, low mid accélération , it was pulling power wheely
everywhere, but was a bit flat on top, to climb a mountain its the perfect set up. to resume it was a grest feeling
set up (seat of the pantS) but maybe not so effective. My last test whit this set up was in great condition pretty
hard surfaces, -10 C .

Now the set up of my new Guru ( Brock)

My final setting is:
ramp : Cutler IT weight. total 73.63 G, very important to place the weight at the same place they are very sensitive and reactive to tip or hell placement. So my set up is : stock ramp 65G+ 1.98g in the tip+4.15 middle+2.5 heel

Primary spring: Venom 120/310
Helix : Venom 50/44 full
Secondary Spring 140/240 (140/220 was back order and 140/200 was in my mind too soft to atteins my 8400rpm target 2017 max hp are 200rpm higher).

Whit that set up, my sled is completely transform. it will hit beethween 8350/8450 ,and stay there, any timeask for power, this is right there, instant response.Like i said at first it doesn't seems as good as my other set up, but its only because condition was not as good (less traction) it is way faster
than it was. Its what i will call deceptively fast, its the first time since i flash my AC 1100 turbo (vipec 270hp) that came too hot in corner, the setup that Brock put together is Very very effective, it is a perfect fit for what an XCR is made for : A cross country Racer. I can't find the right word to describe how good and effective the set up that Brock have put together, and graciously share whit us ( like you can see my English is not the best).

an exemple yesterday condition was windy and snowy (side wind 3 to 4 inch fresh snow) and it was still pulling is rpm everywhere.
in those condition normally i loose around 200/300 rpm and my sled was not very snappy.

I can not thank's Enought Brock to share is knowledge with us, its the biggest gist i receive since long.

Thank you very much Brock

last note:
1- I'll try when available the 140/220 and the 140/200 secondary i think in certain condition it will pull it easy
2- I'll try original 10/70 or 10/72 to see if it change something
3- If it was to do again i will have try the Cutler TM (more agressive profile) i'm sure it will be a great combination
Click to expand...
Ouch, I don't deserve all that praise bud,lol :eek:
Lots of knowledgeable guys on here Div20
 
Nice sled Shwantz !! Any chance you have more pics for us!. Lol i’m in quebec if you ever come around here! Hit me up!. Want to see that in person!
Brock also gave me the right direction to go and it work’s great on mine too!.
 
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