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TPI 911 Response Clutch Cover

LoudHandle

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The stock clutches are two plane balanced as a unit from the supplier (Team). They drill holes to achieve balance in both planes; the cover and the fixed sheeve.

Any changes you make to that Assembly; including shimming the spider for belt clearance. The clutch should be rebalanced.

Some like me would balance a stock clutch with zero changes, because the stock balance is too far out for crank longevity. IMO

My preference is Indy Specialties; because they balance as individual components, so when I reshim the spider, I don't have to pay to rebalance it again nor pay the ridiculous shipping charges these days, multiple times.
 
S
Oct 4, 2016
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north pole alaska
yea we have a place hear in Fairbanks that will balance it but they do it as a unit and disassemble nothing. indy balances each part separately I believe and then gives a final balance when its back together. if it was dun that way from the beginning I could just put the cover on and it would be fine as the cover is balanced...or supposed to be... I feel like what I can get dun hear is the minim that needs dun and indy is doing all that can be dun!
 

reifnote@msn.com

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Dec 27, 2007
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I have been using the same 911 clutch cover that I bought from Duane back in 1999 on every one of my sleds since then. My last 7 sleds have been Silber Turbo rmk’s. The cover has been on 11 sleds and has to have at least 20,000 miles on it. The bushing is still in excellent shape. This season I added the adjustment ring to it in order to adjust the belt to sheave clearance without reshimming the spider. This makes it crazy easy to fine tune the clearance for butter smooth engagement. I found that I needed to blue loctite the adjustment ring. With the exception of cleaning my clutch after every trip the only other maintenance I’ve had to keep up with is changing weight bushings every 600 or so miles. The larger oilite cover bearing gives the clutch so much more stability and is near impossible to damage when assembling the clutch. I personally think it’s a great product and will easily buy another one if it ever fails.
I have been running the 911 cover on my M-1000 for about 3 years. It is probably the best improvement that I have ever made. With that said, the clutch was in need of rebuilding,so the improvement was more noticeable. Without any balancing it runs smoother, and I gained about 200 rpms. It is the smoothest engaging clutch I have ever ridden. The belt adjustment is great, and I wouldn't want to be without it.

My .02
 

Reeb

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I've also ran a 911 cover from Duane since the 90's. On multiple sleds, currently on a '17 Axys. Wouldn't trade it for the world.

As far as balancing goes, does nobody actually walk into a machine shop and tell them exactly what they want? It might just be me but whenever I need a head cut, or clutch balanced I tell them exactly what I'm after and they do it for me. I balance all the weights, bolts, etc on my gram scale. All I'm saying is that if I'm paying for shop time, they are doing it the way I ask them to...
 

dragonflats

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i would just like to add that all of this is just to the best of my knowledge! I am not collage educated and am not an engineer just a framer but i have ben playing with clutching for 20 years on all my sleds and all of by buddy's also. 90% of what i learned is from trial and error and reading! i have never hade the chance to run any of my philosophes by an engineer but i think its physics that mass = harder to spin = less spinning = less rpm i am sure some one on hear is laughing their a$$ off at my laminas explanation of what i THINK i understand :) but like i said this is all just to the best of my understanding! and i just put nails in wood for a living.
Don't forget it's the knowledge of where to put those nails in the wood that makes a difference.!

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R

Ratchit

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Great subject.:)

We run 3 different covers. Stock,Zollinger and Indy Dans.
All great products. You can see the weight difference. I like Zollinger cuz you can use Polaris oem bushing. Indy dans is great too as bushing is better with more contact area. The Zollinger with titanium bolts is the lightest by far and quality built. Indy Dan’s is pure quality too, it’s heavier but tolerances are better then stock.
Can you see or tell the difference in a short race??Not really as we tried all of them pictured and what’s more important is , the spring pocket and how it changes starting rate/ft.lbs. Measure all of them and there is a difference. Stock has variances too. Stock isn’t exactly 2.50” to 1.19” on different clutches. All vary and the custom clutch covers change this too.
 

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Reeb

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I’m having a hard time with my 911 cover right now. I have the spider shimmed so I don’t really need the adjustment but I can’t find a spring that lowers my engagement much. The difference between a 160 and 120 start rate was not even noticeable.
Maybe I need to add more weight to the heel of my weight. Pulls good but on top end it feels stronger at 7900rpm than at 8300rpm(Axys with SLP pipe and head) and it started to act this way when I put the cover on from my old sled. Time to go back to stock and figure out what misstep I took along the way.


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b-litt

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I made the mistake of running the ZRP cover without balancing. 2018 Axys 155 with SLP pipe and can. I try to clean the clutches with compressed air between every ride. At about 500 miles I noticed the billet cover was cracked in three spots and about to go. Two others in town had their ZRP covers fail taking out oil res, lines, and crank. Out of the two with twisted cranks one was stock the other boosted.
It's a great way to shed rotational mass. Just take the time to do it the right way.
 

Reeb

Modding mini's
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I made the mistake of running the ZRP cover without balancing. 2018 Axys 155 with SLP pipe and can. I try to clean the clutches with compressed air between every ride. At about 500 miles I noticed the billet cover was cracked in three spots and about to go. Two others in town had their ZRP covers fail taking out oil res, lines, and crank. Out of the two with twisted cranks one was stock the other boosted.

It's a great way to shed rotational mass. Just take the time to do it the right way.



Good to know. I just ordered one for stock along with a bunch of other stuff. I’ll make sure to get the entire clutch static balanced after we sell it.


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