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Clutching, my findings

WyoBoy1000

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Red Lodge MT to North, CO
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I took the spring out of my primary and bolted it back together, then moved it in and out, about 1/4" before the sheaves touch the clutch binds and sticks. Then with the bolts removed and hold the cover on it slide in and out easy, not only on the last 1/4" but the whole way.
So with a load on it I would say its binding all the way.
One of the bolts did not want to go in easy so I opened that bolt hole 1/32" larger and it seemed to help without the spring.
But when I rode it there is something wrong, (get back to that)

I also found there is some bind in the secondary spring, it does not let the spring twist and it works more like a torsional, but if you where at anypoint in the shift and it did twist-- it would work like a backwards torsional and really mess with backshift.
So I machined the helix and took 2 thrust washers/torington bearings and put them in the helix. Basically a shift assist. I also left out both plastic washers.
Heres the prob.
By freeing up the secondary it should have pulled down rpm in two ways, 1st I took the spring bind out, 2nd I removed both plastic washer and the shift assist is shorter than one washer (so not much but still pulled some spring pressure).
On the trail it felt like it wouldnt shift, rpm's would spike way above where they should (well over 8300) which I have never seen, so when you wack the throttle there is instant rpm spike and then it tries to pull.
Then on the hill (few inches of fluff and hard base) they spike but sometimes would only hit 7800 and then climb to 8-8100, or sometimes spike and pull down to 77-7800 and then back up. Later in the day it started to hit 7800 and in a flash hit 8050. But you could hear it.

My take is the longer I ran it the better in got like it was re breaking in the bushings. But with the MDS weights (tip loaded) in should have shifted sooner without as much rev up before the shift, especially with a freed up secondary.
All I can think is my primary is binding, as the secondary should be better then ever.

I also added motor mounts and still got a little chatter once in a while.

I also set my clutch alignment exactly at 1.484, I had a belt that was pulling cords and it stopped, heres to hopping, but with the other issue I am getting to much heat, not extreme but to much and after back to back pulls in harsh throttle you start to smell the belt just a tad.
 
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winter brew

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Can you put the secondary back to the way it was to isolate that one change?
Interesting result...sort of the opposite of what theory would predict....now to figure out why. :face-icon-small-hap I love this stuff!
Was there ANY other changes to the sled between tests? Different belt? different clutch spring? Any panels removed or something changed that would allow snow in there?? just to narrow down the possibilities.
 
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Devilmanak

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Is 1.484 where they are supposed to be set? I had read a different number.
My offset has changed three times now. Update, set, ride, changed. Reset ride, changed. Reset, ride, haven't checked again.
Check it, then rotate your sec clutch 180 degrees and check again, I get different measurements. Clutch is machined wrong, jackshaft is bent, or clutch isn't staying centered on shaft.
I did check my primary the other day with bolts in it, it is super smooth the whole way, but my spring looks like it came of a 96 ZR, it is beat to death and missing paint after 450 miles. Cannot find anything it would be hitting.
I also found secondary bind myself a couple weeks ago, moving the sheaves by hand while changing a belt. Nasty clunk when the sping releases.
 

WyoBoy1000

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I had a drilled bolt with one washer in the tip of each and was high so I added another washer to the tip of each, my finding with these weight is if you want more shift sooner is to load the tip, to get more rpm before shift add in the middle.
So could you explain why you say balance the weight.

I also noticed the shift got better the more I ran it (really noticeable after the first few miles), like the clutch bushing was starting to work better but still had , or what felt like bind. Thus I think the clutch cover is causing problems. Or something.

When I put the weights in in WA I had bolt with 2 washers in tip and bolt with hole in the middle and the shift started at a lower rpm than the stock weights. almost like I needed to move a washer from tip to mid.
 

WyoBoy1000

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Can you put the secondary back to the way it was to isolate that one change?
Interesting result...sort of the opposite of what theory would predict....now to figure out why. :face-icon-small-hap I love this stuff!
Was there ANY other changes to the sled between tests? Different belt? different clutch spring? Any panels removed or something changed that would allow snow in there?? just to narrow down the possibilities.

To much changed to be sure and I can't go back, but I am sure there is a bind, I need to find another PC setup in my area and swap the primary and secondary back and forth to see whats going on, or if there is any difference.

In theory I should have noticed the opposite, the change weren't really major.
Slightly modded clutch cover -- could have gone the wrong way
shift assist in secondary with basically one less plastic washer worth of pressure -- should have pulled r's down and lower shift rpm

added mounts to try and keep tcl from moving up and down-- shouldn't have made much difference in normal operation.
 

winter brew

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Is it designed (secondary) with a certain amount of resistance?? Sometimes what we interpret as a bind on the workbench will work flawlessly under rotation and pressure.....the bind may be insignificant or actually beneficial...??? Some mechanical devices are designed with built in preload to keep things tight as they wear....if things operate TOO smooth that means there is room for movement and will wear quicker. I can see that being the case on mass produced secondaries....engineers do weird things!

Are you trying to correct the clutching or trying to determine why the results were not as planned?
 
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aksnopro

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After several pulls and testing i noticed one major thing. If the. Clutches were cold they were hitting proper r's and holding it nice, if they were hot they were all over the place like the heat is creating tolerance issues or the belt performs different with the heat..

Just thought i would que you in if you want anything consistant in testing, cooling them down before each test seems critical to me.

-Aksnopro
 

WyoBoy1000

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The way the secondary spring is setup there is to much room for inconsistency. IMO there is now way letting the spring twist free is worse in the long run with the right setup.

Belt temps are not a factor in what I am talking about, yes it does act different but the same if considered temp.

I am trying to get better backshift and longer belt life, with the stock weights I was seeing as much as 400rpm change at wot and 300rpm change with the MDS (those are extremes) and average 300 stock, 2-250 MDS. Usually I have been able to get the MDS to hold within 100 or less on average.
So I'm targeting the backshift,
Now the way it is when it hits 8050 it holds it for the most part, almost dead on, but if you blip the throttle its inconsistent and hits 78-8000 then up to 8050.

It acts just like spring or bushing bind.
 
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aksnopro

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Im sticking with my statement i think the secondary sheave bushing is too loose, causing binding when certain jackshaft wobbles are present under load. The team is curing peoples issues because the sheave bushings aren't binding under this condition..


All speculation of course, keep testing! Tomorrow i will have solid information on temps with 083, 084, team tied, and mds weights!

The difference i saw from hot clutches to not hot clutches blew my mind, im talking 6 sled lengths in a race and 4 to 600 rpm change.

Will post all my temps and results from testing tomorrow.

You notice any cooler belts with the motor mounts?

-Aksnopro
 

WyoBoy1000

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I think they where cooler than before, but can't say for sure why. Usually I try and do one thing at a time but I have limited time to ride so thats out.

In this video at 57 sec you can hear a squeal, I think its the clutchs when I loaded the track. (might be wind or something) but it goes with what I've said about improper shift.

http://www.youtube.com/watch?v=nDLR...DvjVQa1PpcFPFDjutxRY5DNXWAKnJtnSrFeTHTFdXFcs=
 

CATSLEDMAN1

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if possible add a spacer back to the secondary spring and increase belt grip a little. On the Ms with just .100 more pressure shift changes are noticable, erratic rpm is very often upshifting secondary before primary can handle it.

Too much secondary side squeeze you'll know becasue upshift begins to slow.

When we got our first team secondaries for firecats, they would'd work in mtn riding until team made some longer stiffer srpings, until then erratic rpm and belt heat.
 
G
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After several pulls and testing i noticed one major thing. If the. Clutches were cold they were hitting proper r's and holding it nice, if they were hot they were all over the place like the heat is creating tolerance issues or the belt performs different with the heat..

Just thought i would que you in if you want anything consistant in testing, cooling them down before each test seems critical to me.

-Aksnopro

have definatly gotten my clutch temps down to a science i can immediatly tell when they want a break.. cuz ill see 7500 to 7800 rpms once i been thrashing around in and out of the throttle. Looking forward to hearing how the team tied and MDS treats you. DO YOU have white rads motormount installed? if so whats ur thoughts and any benefit?
 
F

Flatbed

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I had the same problem on my 09 as Wyoboy is having now. NO matter what I did to my cluthing, mainly the primary, the rpm's did not change. I had a 6 gram difference in weights and also changed springs in primary clutch. Sled would not tach above 7600. All my changes were done on the hill, same day, same hill. So I pretty much ruled out the primary as the problem. I ordered a torsional kit, installed it and as soon as I left the parking lot I knew problems were solved. My son had the same problem on his M. He switch to a torsional. Same results. In my opinion Cat's secondarys suck. A lot of people don't have secondary problems but on the other hand a lot of people do. Same with the pro climb. Why? Is it quality control or something else. It's the same thing with Pol. and their motors.You would think by now the engineers who design this crap could figure out how to solve their issues. Am I venting? Yes!
 

WyoBoy1000

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if possible add a spacer back to the secondary spring and increase belt grip a little. On the Ms with just .100 more pressure shift changes are noticable, erratic rpm is very often upshifting secondary before primary can handle it.

Too much secondary side squeeze you'll know becasue upshift begins to slow.

When we got our first team secondaries for firecats, they would'd work in mtn riding until team made some longer stiffer srpings, until then erratic rpm and belt heat.

I would agree other than the shift is way to slow to start with.
Also the shift assist should increase the effective pressure.
Maybe you are right about the top rpm, but it reving way up before shift is something else.
 

WyoBoy1000

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I had the same problem on my 09 as Wyoboy is having now. NO matter what I did to my cluthing, mainly the primary, the rpm's did not change. I had a 6 gram difference in weights and also changed springs in primary clutch. Sled would not tach above 7600. All my changes were done on the hill, same day, same hill. So I pretty much ruled out the primary as the problem. I ordered a torsional kit, installed it and as soon as I left the parking lot I knew problems were solved. My son had the same problem on his M. He switch to a torsional. Same results. In my opinion Cat's secondarys suck. A lot of people don't have secondary problems but on the other hand a lot of people do. Same with the pro climb. Why? Is it quality control or something else. It's the same thing with Pol. and their motors.You would think by now the engineers who design this crap could figure out how to solve their issues. Am I venting? Yes!


The M is way different, I went through everything with my M's so I have a good idea. this feels more like a stock pro than anything, r's up, then shift, then stall out.

I'll have to tear into it and see what I find but I'm pretty sure my problem is in the primary, maybe drilling that one hole bigger screwed it
 
G

geo

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After several pulls and testing i noticed one major thing. If the. Clutches were cold they were hitting proper r's and holding it nice, if they were hot they were all over the place like the heat is creating tolerance issues or the belt performs different with the heat..

Just thought i would que you in if you want anything consistant in testing, cooling them down before each test seems critical to me.

-Aksnopro


I'm pretty sure this will be the norm with the 084.
 
G

Going West

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If it didnt act like this before you messed with the secondary then why would you think its the primary. Drill one hole a tiny bit larger will not make any difference, there are still 5 other bolts that line the cover plate up. You modded the secondary so start there. JMO

I had my primary replace because of the cover causing a bind and sticking. It did not act like this, I only noticed it when I stopped and the clutch would not disengage. I'm sure it was effecting how it worked to a degree but nothing like what your experiencing.

Im going to try a torsional set up, but Im just going to drill the helix I have, I dont really want to wast the cash if it doesnt help.
 
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geo

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Wyo. Do you have a orange to try (now that you have room for it). What Catsledman was saying is true. Funny thing is the secondary needs more grip at the beginning than in OD (think about the turbo clutching thread and what they need) because there is more torque applied to it (belt lower in primary, like 1st gear on a10spd). Even though the diameter is bigger, there is about 4 times more torque applied to it from the primary.
Once the belt starts slipping it is hard to grab it again.

Talk to Steve about the weight into the middle hole. Works this year with the stock secondary and MDS ( but not the Tied IMO) unlike last year with the smaller secondary.


Speaking of alignment (you changed alot at one time LOL), I,ve been playing with mine. I've been asking myself "who's pulling who" (primary or secondary). With the solid jackshaft it was the motor that moved. Now what?
I use magic marker lines to prove-disprove if my clutches are pulling my belt true in the sheaves. I always let those marks tell me where to put the secondary for off-set and engine for unparallel in the old days. Your final setting was a comprimise to be lived with but it worked.
This year I looked at the marks on the primary and all was good (I thought) This TCL system is not as advertised as we all know now. Alignment does change. Lot's of theory, lot's of ideas, lot's of threads. It could be the motor movement, it could be chassis flex, it could be TCL flex, it could be jackshaft flex, it could be all of the above. All I wanted to find out was what is the best place to set my clutches as I got it now. I do not have any motor stiffening devices attached. I was just going to believe the marks (like in the past).

In the past if you changed alignment you saw it from the wiped out marker on the primary mostly. My experiment was to move the secondary shims beyond the recommended alignment range and watch these marks.
What I found; First I took the float out of the Tied and all shims out from behind the secondary. I marked my clutches and did one full throttle blast to 60, applied the brake and backed off. Check the marks. Then I changed my alignment huge, added .300". Did the same run.
Both runs showed the belt running true in the primary (equal on both sides). Both runs showed the alignment way off in the secondary. And both runs got the belt too hot to touch in , I don't know maybe about 60 seconds.
I removed shims behind the secondary .060" at a time until I went past true on the secondary marks, then adde a .030". The difference in belt temps in those 6 60 sec. runs was huge. I could not believe how much heat you can make in a short run with alignment way off and even the last .030" shim was noticeable to the hand.
After that I did a little test section I use through the trees with a hill and checked belt again. This is the closest I have been this year to being happy with what I felt. Nothing changed just alignment shims.

So I learned the primary is pulling the secondary (unlike the past) and MY alignment is not per book. I won't say this is the spec (but I am .080`different from before) because I really believe what ever is flexing (and it is more than likely more than one thing) and how much, has got everything to do with how much throttle you use, how much traction you have, the average mph you ride at, how hard (or not ) your clutches are pulling and even the type of clutch you are using.

I believe my marks. Today I will reinstall float and try it. If I don`t like what i see and feel I will mount it rigid again.

So here's what I found and take it for what it is, MY findings.
 
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