Wow, then there must be a big difference between the '19 and the '20. I have yet to ride this year but that is very surprising.
Maybe I should stop on my new 800 build and buy a 2020 840.
Its a big difference, they pull alot harder
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Wow, then there must be a big difference between the '19 and the '20. I have yet to ride this year but that is very surprising.
Maybe I should stop on my new 800 build and buy a 2020 840.
Seems HIGH, but I won't argue. Anyone else?I think i still have some to gain with heavier weights but im mid 40s while digging hard, not hitting it at the bottom full speed already but playing mid hill then pinning the flipper.
6-8k ft elevation heavy deep snow
163 2.6 stock gearing, 250lb rider weight
Why does going fast have to be so hard
I have 10 year old EPI jam nut and spider tools and clutch holder. Have taken apart well over a dozen with ease, honestly has been harder getting clutches off sleds.Any new tools that might make this easier. Seems when I pull the spider they are so tight they almost break coming apart and I have broke a couple. Thanks for all your help TRS
Best clutch info on the web this year!There are two very critical pieces to the puzzle regarding clutch efficiency and performance. They are your belt to sheave measurement and belt deflection. I’m going to cover one of them here. It is imperative to shim the primary to a belt to sheave measurement of .015-.030”.
This should be checked and adjusted for any combination of belts and weights. Factory or aftermarket.
Ive seen factory clutches with a belt to sheave of .120”. If you installed TRS weights in that particular clutch you would have a .150” belt to sheave measurement.
When you open up the belt to sheave from .020” to .060” you will witness a measurable loss in operating rpm and track speed. Think about that for a moment , what happens as your belt wears out..........Did the light come on?
The moveable can only travel inward the amount the weight commands through centrifugal force and total shift. If your belt to sheave is to wide you will reduce the amount of belt shift out in your primary as a worn belt would. This also gives a false 1:1 ratio because of your weight to roller contact point.
Do yourself a favor and adjust your belt to sheave to help extract all you can from your primary, no matter who’s kit you run.
External belt adjusters are not the answer. They only move your rollers away from the weight, it didn’t change anything. The weight still has to make up the gap. You lose the initial shift force of the weight. The max amount of a weights clamping force is initiated at first movement and degrades as it moves through its shift.
If you have your dealer do this service, ask if the technician has performed this service before. This is very important. It’s not rocket science but there are procedures to adhere to. Most don’t. Educate yourself on the procedure so you can decide if you want to tackle it yourself and to make sure your tech does it properly. The clutch should have the weights you are going to run installed along with your choice of belt(new one)
There are things you can do to make sure the tech did it properly and allows you to check his work. Measure your belt to sheave after the service.
But first mark your clutch sheaves prior to taking it in or doing it yourself. Set it on the bench and mark your stationary, moveable and cover in a straight line. Do this preferably where the cover has the X. I use a center punch To mark them, that way they are permanent. These marks must line up after service for proper clutch balance. The spider can be located In any of the three towers to achieve this. It is imperative that they line up very close after adjustments are made.
Here is some extra infoView attachment 336734View attachment 336733
Ive seen factory clutches with a belt to sheave of .120”. If you installed TRS weights in that particular clutch you would have a .150” belt to sheave measurement.
The moveable can only travel inward the amount the weight commands through centrifugal force and total shift. If your belt to sheave is to wide you will reduce the amount of belt shift out in your primary as a worn belt would. This also gives a false 1:1 ratio because of your weight to roller contact point.
External belt adjusters are not the answer. They only move your rollers away from the weight, it didn’t change anything. The weight still has to make up the gap. You lose the initial shift force of the weight. The max amount of a weights clamping force is initiated at first movement and degrades as it moves through its shift.
Thanks for your question.Great post but help me out a little. Starting at the top of the quote
For the TRS weights I measured .020 not .030 increase compared to the stock weight. Is this not right? Unless I wrote it down wrong, I could double check.
Assuming the belt is good and the same in both sheave clearance scenarios, lets say .02 vs .06.
The belt should contact the sheaves on engagement at the same spot and climb through the sheave till full shift when the sheaves contact and stop the movable. Im not seeing why the extra clearance would change where the belt touches the sheaves and prevent full shift like a narrow worn belt. Weight to roller contact point, yes the shift pattern and belt clamping changes. Will the weight not have enough force to shift out with the different contact point?
Moving the rollers away from the weight causes the weight to "untuck" so moving the COM of the weight out from a more tucked position under the pin loses force?
Thanks for your help, I appreciate everything you do on here
It is very noticeable.tony,
do your weights move the sheeve tighter to the belt or make it looser?
how much performance is lost by not shimming the spider with your kit?
i am trying to get my ducks in a row to get the spider shimmed when i receive your kit. however, this has become a challenge and i will probably have to invest in all the tools to get this done properly
thanks