Is The Carls Cycle Primary Shave & Balance Worth The $

[ghost rider]

Just wondering if there is anybody that has had first hand experience with the Primary Clutch Mod Carls is doing? They Shave both Sheaves of the Primary Clutch to match the angle of the belt and balance it true afterwards. It is sappose to make the clutches grab the belt better cutting down on slippage and reducing belt heat. Therefore getting more power to the track.

But the guy that I have had balance my clutch in the past charges $65 and Carls is charging $175 plus shipping. It sounds logical, but just want to here of somebody that has had it done and if they saw a big difference in performance vs stock to justify spending the extra coin. Thanks

 

[Avi8tormd]

My friend and I both had this done and we felt that it made a difference compared to a stock sled. Machining of the clutch faces to match the belt angle makes sense. It was worth it to me.

My 2 cents.

 

[Oregonsledder]

My friend and I both had this done and we felt that it made a difference compared to a stock sled. Machining of the clutch faces to match the belt angle makes sense. It was worth it to me.

My 2 cents.

This may be a dumb question, but don't belts wear-in and then match what ever angles that exist on the sheaves? Belts wear over time and it's hard for me to believe that they don't soon match the sheave angle. Now if their process is to make sure the angle is correct and the same on both sides for better performance then I might buy that, but to just adapt the sheaves to some particular belt angle doesn’t compute with me. All belts are not the same even with the same part number... I have measured new belts and have seen the difference.
I have no experience with what Carls does, but it does not make sense to me.
I will probably hear some one say... I don't know but it seems to work. I would need more of an understanding before I would spend that kind of money and have precious metal removed from my clutch faces.

 

[Avi8tormd]

This may be a dumb question, but don't belts wear-in and then match what ever angles that exist on the sheaves? Belts wear over time and it's hard for me to believe that they don't soon match the sheave angle. Now if their process is to make sure the angle is correct and the same on both sides for better performance then I might buy that, but to just adapt the sheaves to some particular belt angle doesn’t compute with me. All belts are not the same even with the same part number... I have measured new belts and have seen the difference.
I have no experience with what Carls does, but it does not make sense to me.
I will probably hear some one say... I don't know but it seems to work. I would need more of an understanding before I would spend that kind of money and have precious metal removed from my clutch faces.

Sorry for the cliff note version. Call Jack at Carls and he can give you long encyclopedia version.

Also remember that this mod includes balancing.

 

[mountainhorse]

I hear ya oregon... but the 115 belt really does not break down that much ... in fact, they wear the clutchs out faster than previous belts.

It would take some serious use to "Wear it in"

The 115 belts are Extremely close tollerance belts (ground to dimension)... I've not seen more than 0.05" variance belt-to-best in a wall of them at the local dealer. (don't ask me why I took the time)

 

[pura vida]

it's ok MH, i've done the same thing. even the guys at the local shop that know me and how i am gave we weird looks when i brought in my digital calipers and asked to see every 115 and 122 they had. (lots of eye rolls) i did find some differences but they were so small i doubt they would be relevant in the real world. (i still bought the widest ones though...) although that brings up the question, at what point does it start making a difference? considering your primary will develop more "slop" fairly quickly in the bushings and bearings if it is ridden hard. which begs the questions how much slop is too much and how long to people expect their primary to last? how many consider it a wearable item like i do? i pretty much figure i need to replace my clutch at least at the beginning of each season. too many times i started chasing clutching gremlins that i couldn't figure out only to have my primary fail a few hundred miles later. buy a new clutch, have it all tuned up, and magically the gremlins go away and the clutching is back to where it is suppose to be. i've had this happen to primaries with less than 1000 miles on them. some and sometimes worse than others.

to the OP, i've also had the carl's clutch mod done but mainly b/c i was already sending it to them to be balanced and indexed. can't say how much of a difference there really is b/c i had it done before i ever rode the sled. although if i wasn't already sending the clutch to them i probably wouldn't go out of my way to have it done. hard to say though...

pv

 

[HighmarkerX]

How is the carls mod different to what Indy Dan does? I am trying to decide who I should send my clutch to. Thanks.

 

[gman086]

Just wondering if there is anybody that has had first hand experience with the Primary Clutch Mod Carls is doing? They Shave both Sheaves of the Primary Clutch to match the angle of the belt and balance it true afterwards. It is sappose to make the clutches grab the belt better cutting down on slippage and reducing belt heat. Therefore getting more power to the track.

But the guy that I have had balance my clutch in the past charges $65 and Carls is charging $175 plus shipping. It sounds logical, but just want to here of somebody that has had it done and if they saw a big difference in performance vs stock to justify spending the extra coin. Thanks

Try a search... it has been covered many times here. And yes, I have it and didn't even install my Holz vents last winter as the clutches and belt were always cool to touch even on the worst cascade concrete dayz! More worthwhile than their clutch kit (which I also have) if you ask me.

Have FUN!

G MAN

 

[volcano buster]

My understanding is that the machining isn't necessarily matching the angle, but truing the faces. Picture a dial indicator running across the sheaves like an old record player as the clutches are turned. The machining makes this surface smooth to the dial indicator instead of having high and low spots.

Am I close?

 

[NapaMatt]

My understanding is that the machining isn't necessarily matching the angle, but truing the faces. Picture a dial indicator running across the sheaves like an old record player as the clutches are turned. The machining makes this surface smooth to the dial indicator instead of having high and low spots.

Am I close?

..

Picture a V-Pulley... with different angles on each side.. this making the belt.. always slipping (very) little..

After carls gets done.. Both sides.. match the angle of the belt..

this help ??

 

[volcano buster]

I understand the angle issue, but I have also seen pictures of a shaved sheave that did not have material removed evenly around the faces. I pictured this to actually true the face for even pull on the belt. Just because the angle is the same as the belt does not mean that the faces run exactly true.

Back to my example of a record player. With an unshaved clutch but with sheave angles matching the belt sides, you might be able to put a dial indicator on the surface of the sheave, for arguments sake at mid-distance representing a 1:1 ratio, then fire the sled up without a belt. The dial indicator doesn't care about the angle of the sheave but more about the lateral deflection that the belt must move to stay in contact with the sheave. Now, you have an opposing sheave that may deflect in parallel to the first, or it may deflect the opposite direction. If the latter is true, the gap between the sheaves increases for a short distance causing the belt to slip down into the clutch until the sheave distance chokes back up causing the belt to ride back up. I can only imagine this causes severe belt heat when running at high RPM's and high load.

If I am correct, then having both the angle and surfaces trued and matching, then the clutching should work and respond tremendously better and the belt should last longer.

 

[NapaMatt]

Yes.. Volcano...

You are thinking right...


Yes after machining them i would think it would be better..

???????

So does any one want to check angles on used belts.. to see if there wearing to fit the angles or there is no change..

Would be neat to find out??!!!

 

[73 Starfire]

Why not do the secondary as well?

 

[AkLogan]

Team prolly does a better job on matching angles then polaris does.

 

[gman086]

I understand the angle issue, but I have also seen pictures of a shaved sheave that did not have material removed evenly around the faces. I pictured this to actually true the face for even pull on the belt. Just because the angle is the same as the belt does not mean that the faces run exactly true.

Back to my example of a record player. With an unshaved clutch but with sheave angles matching the belt sides, you might be able to put a dial indicator on the surface of the sheave, for arguments sake at mid-distance representing a 1:1 ratio, then fire the sled up without a belt. The dial indicator doesn't care about the angle of the sheave but more about the lateral deflection that the belt must move to stay in contact with the sheave. Now, you have an opposing sheave that may deflect in parallel to the first, or it may deflect the opposite direction. If the latter is true, the gap between the sheaves increases for a short distance causing the belt to slip down into the clutch until the sheave distance chokes back up causing the belt to ride back up. I can only imagine this causes severe belt heat when running at high RPM's and high load.

If I am correct, then having both the angle and surfaces trued and matching, then the clutching should work and respond tremendously better and the belt should last longer.

No. The stock sheave faces are fine but one on the primary is the wrong angle. This is the one that gets machined to match the other angle (which is also the same angle as the belt) so ONLY ONE SIDE gets machined.

Have FUN!

G MAN

 

[Oregonsledder]

I'm a big fan of balancing clutches. I work on many clutches in my shop each year and the reason I'm a bit of a skeptic on the shaving the sheaves (on a new clutch) is that a Mt. sled clutch that has as few as a couple of hundred miles on it will already begin showing ridges and valleys. Boondocking sleds often show this the most becuase guys often hold a set RPM for long peiods of time. I can see cleaning up the faces on a clutch that has sheave wear so that the shifting transistions are smoother, but I have yet to hear a good argument for doing this to a new clutch.

 

[1Mike900]

Correct Oregon, I would at least wait for about 500 mi. and then do it. I bet the whole clutch warps slightly from heat cycling. Mike

 

[AkLogan]

Me and a Buddy are doing this one clutch is brand new and the other has 800 miles on it. I think doing it from the start is the way to go. Your talking about the clutch having highs and lows in it. Well you are also starting out with a non perfect surface so the wear is going to be uneven and cause the face to get worse. Where starting with the clutch new and have it perfect from the start it is going to have much better and more even wear to minimize the highs and lows. This is how i see it working out.

 

[magic23]

if you feel at the primary clutch you will feel that its two angles on it,i think their maken it just one angle

 

[Oregonsledder]

Me and a Buddy are doing this one clutch is brand new and the other has 800 miles on it. I think doing it from the start is the way to go. Your talking about the clutch having highs and lows in it. Well you are also starting out with a non perfect surface so the wear is going to be uneven and cause the face to get worse. Where starting with the clutch new and have it perfect from the start it is going to have much better and more even wear to minimize the highs and lows. This is how i see it working out.

The highs and lows are from the belt sitting in one spot under load for longer periods of time that other spots on the sheave faces. Changing the angle of the faces won't change that... all clutches wear that way over time.