Clutch guru question

[tdblakes]

So I've been tryin to learn clutching and doin it myself this year... 2012 RMK Assault. So I marked my clutches and worked my sled this weekend. I spike around 8350 and hold about 8200 under load. Does this picture mean I'm not getting a full shift on my primary and I should go to a softer primary spring?

 

[AdrenalineAddict]

Not necessarily, an oversprung secondary can also hold you from acheiving full shift. The only time your belt is going to ride that high in the primary is when you are smoking across a hardpack lake at 85 MPH. I did some serious road racing this weekend on 12" of fresh and could only hit 76 MPH, I only went full shift (which is where your marks are) on one icy stretch where I shifted out at 86 MPH. If you weren't doing 80 your belt is never going to contact that part of your clutch.

 

[Dartos]

You will only get a full shift at maximum track speed like running down the trail at full throttle. In the powder you will not see a full shift nor should you.

 

[tdblakes]

Thanks for the reply guys. Yea my max speed on the trail was 78mph. Stock gears, stock helix, SLP black purple secondary spring, SLP green pink primary spring, MTX 71g with 2g in the belly and 2g in the toe. I'm pretty happy how it pulls right now. I have a SLP blue pink primary spring too that I might try. Had Indy Dan surface and balance my primary, it's a fair amount smoother than my cousins stock 2012 Pro. Runnin at about 1000ft. Wonder how Carl's helix would fit into this setup...

 

[theultrarider]

I assume you have a 155" track. I'm also running 71g mtx's with 2grams in both holes. Blue/pink spring. I've always like the green, but this sled still comes off the line hard even with the blue. However I am running a 60/40 helix with the stock secondary spring. Pulls like a freight train and the r's don't wiggle. Very happy with this setup 0-3000'. I say 3000 cuz that's the highest I've been with it yet. I have no doubt doubt it will pull this setup closer to 5k. In the 155's they've been ruuning the 60/42 and having similar results. Not sure what Carl's angles are.

 

[xc6rider]

I have the same deal... This can be common. Typically too tall of gearing for the riding you did, or clutch alignment.

I ran more than enough long pulls, climbs etc... Without finding full shift in the riding i did, ill drop gearing. But, only AFTER i verify my alignment is right on.

 

[F-Bomb]

super hard to say...your full shift mark isn't bad but it appears to fade off of the correct spot quickly...confirmed with your RPM experience comments (gotta think that is your horrific RPM fade that is eating 15% of your snort)

Try less secondary tension and be ready to throw some tip weight...do the secondary spring first. (think you'll find that will be a bit better balance based on what I see)


What we can't tell without field testing against a comparable vehicle or in a timing trap is how things are working up to the point when it's all falling apart. You say it pulls good so basically you have some level of happiness but one man's good might be 10 lengths behind another! It's all perspective! There is a lot too it and heresie theresie is tough with mixing programs.

I'd say try to duplicate theultrarider setup since you are already on that path plus similar alts. You guys with "good" setups will find that the buggy will be far more flexible in alt changes as well. Your R's remain very constant it just takes you a slightly longer duration to get from A to B. It's another magic benie to good clutching/transmission on these sleds. Once you finally get outside of your good parameter you simply add or subtract weight. It's cool because you get a great running buggy in a vast variety of areas. Not important for those that never travel but HUGE for those that start out quite a bit different in riding alt or go all over the world to play.

Here is my GOOD reference:
Hammer from idle packs the skis 6"...instantly to 8000RPM and stays there. Uphill downhill over the hood or hard pan. You get 1400 miles on a 115 belt and you don't have to buy aftermarket vents. Pulls the same 64 gram weights from 4000 to 8000. (there are other more shallow and superficial rewards like KICKING EVERYONE ELSE'S BUTT all day every day until the rest of the world catches on) Based on my snowest readings many many are ferociously reventing the wheel and we should have some REAL competition very soon. Well ok maybe not soon but hopefully prior to 2013 when we get a new vehicle and have to start all over!

 

[tdblakes]

so going from a 56/42/36 to a 60/40/46 helix is going to make my sled upshift faster and hold rpm better but it wont backshift as fast? parts fiche says stock secondary spring is blk/pur, which is what I put in there. I could've swore i pulled out a solid black spring... hhmm

how will that helix change affect things if I take my sled up to 9-11k ft? If I got my clutching down right it shouldnt matter and I should only have to change weights right?

Found 2 helix's for the tss-04... in the WPS Catalog I found a 60/40/36 and on SLP's website if found a 60/40/46. What will be the difference between them?
Ultrarider, which are you using?

 

[Old Scud-doo]

so going from a 56/42/36 to a 60/40/46 helix is going to make my sled upshift faster and hold rpm better but it wont backshift as fast? parts fiche says stock secondary spring is blk/pur, which is what I put in there. I could've swore i pulled out a solid black spring... hhmm

how will that helix change affect things if I take my sled up to 9-11k ft? If I got my clutching down right it shouldnt matter and I should only have to change weights right?

Found 2 helix's in the WPS Catalog. 60/40/46 and 60/40/36. What will be the difference between them?
Ultrarider, which are you using?

Black spring could have been the stock 140/330 Polaris primary spring.

In theory, only have to change the weights when you go up or down in elevation.

46 and 36 is .46 and .36 for the lenghth of the intial angle of the helix. 46 being longer and probably would rob you of midrange rpm and backshift.

 

[Skeld]

My sled has the Black spring in it and it was set up for 6000 to 8000 feet stock. To go down to sea level, I only had to change the weights to 68's from 62's.

 

[theultrarider]

I'm running the .36. Sorry. Should have that to begin with. The 60* is

steeper than stock and will upshift quick and pull harder out of the hole. Helps to load the motor up. Now the 40 is less angle than stock but only by 2*. Didn't really notice a loss of up shift but do see better backshift from the shallower helix.

As said in the above post the .36 helix means the shift point btwn the angles is .36" from the start. Or at about 18mph. There is so much torque in this motor down low that backshift on the bottomend isn't a problem.

I may only be riding at 0-3000' but here in Alaska, that is still steep and deep country.I rode all day Monday and Tuesday in waist deep to chest deep pow and it didn't matter what I pointed my sled at it ran at 8000 rpm +/-50 when I would playback a recorded run on the tach.
I know all I would have to do to go up in elevation would be to lose some tip weight.
As for heat, I can't say my clutches were ice cold, but in that deep of pow and wot everywhere and no venting you expect SOME heat.

Hope this helps you.

 

[tdblakes]

I have a 60/40.36 on the way to test out this weekend. I'll try to remember to report back

 

[GKR]

The "Carls helix" everyone talks about is what you want. Top of head its
64-42 .40 on one track 62-40 .40 on the other. Gives you two options in one helix and both tracks work great. One in deep pow, the other in heavy wet snow.
Order it from Carl's on-line is easy. Bunch of other vendors or classified are worth a look too. As for your marks, if that was a typical riding day and you say you went 78mph you can gear down, one or two teeth on the bottom gear. Everything will improve, belt life, throttle response, track speed in the deep pow and you will likely not suffer any top end loss at all, that's what you have now, your not using all your transmission. Your belt will move about about half the distance of the marks that are left, more or less. Set your belt side clearance in the primary to 0.015 -0.020" (important and often way off)and run your belt tight, close to squealing or creep on a stand. Enjoy, it will all be a noticeable improvement.

 

[aebsledder]

The "Carls helix" everyone talks about is what you want. Top of head its
64-42 .40 on one track 62-40 .40 on the other. Gives you two options in one helix and both tracks work great. One in deep pow, the other in heavy wet snow.
Order it from Carl's on-line is easy. Bunch of other vendors or classified are worth a look too. As for your marks, if that was a typical riding day and you say you went 78mph you can gear down, one or two teeth on the bottom gear. Everything will improve, belt life, throttle response, track speed in the deep pow and you will likely not suffer any top end loss at all, that's what you have now, your not using all your transmission. Your belt will move about about half the distance of the marks that are left, more or less. Set your belt side clearance in the primary to 0.015 -0.020" (important and often way off)and run your belt tight, close to squealing or creep on a stand. Enjoy, it will all be a noticeable improvement.

I think this is the first time I have actually seen the numbers on a "Carl's Helix." For a while I thought it was top secret info protected by the government or something.

 

[tdblakes]

And I asked a buddy that has a carls what the angles were. He told me they were 60/40.40 sooo maybe it is top secret info and they etch random angles on the back of the helix just to keep people guessing! I Dunno. So I ordered the 60/40.36 from team to try. We'll see!

 

[AKSNOWRIDER]

just de[pends what it was ordered for..first year of the dragons 8's it was 62/42/46 and 64/42/46, they changed them for the rest of the dragons and again on the pro's...

 

[GKR]

Tried to confirm the numbers on the Carls helix and my earlier post was a little off. The numbers are 62/42 .40 on one track 60/40 .40 on the other. I just looked thru old threads I had to confirm this but to be 100% posiive, they are stamped on the helix, I just don't have it in my hand. As far as I know this is a propietary grind for Carls, the closest standard TEAM helix's are slightly different, 60/40 .46 or 60/40 .36 I believe you can buy.

 

[ctruck700]

Don't want to steal the great thread just wondering if lower or higher gearing helps pull a steeper helix? Brains going a mile a minute with all this great info. Thanks.

 

[Reg2view]

My Carl's helix for the pro said 62-42.40 and 60-40.40, hand etched, with driven spring Team gold. To confirm, FWIW.

 

[GKR]

Gearing down (lower) will help you pull more helix. Kind of any way, that's not necessarily the proper way to tune but it is a correct statement.
In this case all the clutching (transmission is essence) is not being used so gearing down will take load off the clutches and allow it to shift out further. With less load on the clutches you can generally pull a steeper helix and keep your RPM up.
If I related it to your truck it would be this case. Stock gears in your diffs, you put on big tires and now you can't quite pull 5th gear anymore on the highway and RPM's drop. It's sluggish all thru the gears. Gear down the diffs (same as gearing down your chaincase) and you get 5th gear back and the response all thru the gears is better. Same idea here.
Hope that helps.