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Discussion Starter · #1 ·
Hello , looking for advise on my clutch I had a shop that told me maching is the way to go . So got it done I’m not impressed. My clutch is only running 2.6 maybe on ratio the low end torques not there at all if I shim it I can get 2 mil shims in there still before it touches the cover what’s going on if it was machined shouldn’t I be able to max fit .7 mil ? Thanks
 

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You're leaving us guessing on a lot of elements of your issue... What machine (year & model)? Who machined your sheave? What weights are you running? Is it reassembled correctly?
 
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Discussion Starter · #3 ·
Sorry , 2009 grizzly 700 , shop I’d rather not say there name , but not anyone recommend for machining as I found out . They machined the inner and outer sheave witch is wrong from what I found out .. inner is the belt enlightenment sheave .

Anyways running 660/440 mix weights and purple epi spring low ends not back but non for top speed
Also like said I can fit up to 2 mil of shims and when do so I get very close to 3.1 ratio as well .
 

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Welcome from Colorado.
It sounds like you let someone mess with your machine that doesn't know $hit from shinola.
Your 700 had close to a 2.5:1 ratio stock, so you didn't get much from the work done, thus no noticeable difference from your butt dyno.
The best machining is done by Arnie Cooper, he's the guy that first started this type of work, and he only machines the movable primary sheave. As your ratio seems unchanged you might be able to use the existing parts, that is IF you have everything installed correctly and the ratio is 2.6 to 1. You have to very very precise when counting so we know exactly what you have to make firm recommendations for your next move.
Then...the 700 shim limit without machining is the grease cover screws rubbing the cage, then with machining less shim can be install as the belt rubs the cover. Without machining and the grease cover installed the shim limit 1.7mm's.
This all with stock dimension weights.
 

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Discussion Starter · #5 ·
When I do the ratio My primary stops at 5 o’clock and when I bring it up to 3 on primary the secondary is at about 10 o’clock don’t know if that helps
 

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Coop45 is the guy you want to seek out for Machining your clutch. Most guys on this forum that have machined sheaves was done by Coop and all are very happy with the result. Typically you end up around a 2.95 to 1 ratio. Some come in at 3.0 ratio. With Coop's mod you gain bottom end and lose nothing on top. Typically with a Coop mod you can shim the sheave about a 1/2mm.

 

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That info doesn't help.
The deal is there are 24 veils on the movable sheave and I count to the half vein for accuracy.
Another thread here has a video showing the setting up, turning and the count.
 

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Discussion Starter · #9 ·
Okay I just redid it again and it’s 12 -1/2 of them from where it stops at 1 full rotation
 

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2 and 12.5/24 turns on the primary for one revolution of the secondary? That would be just over 2.5:1 which is near stock...so benefit from machining.
The mechanic may have done nothing for you.
 

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Discussion Starter · #11 ·
Ridgway81432 ,
Well shit now I’m pretty pissed that I spent the money for this that they swore up and down I should do it and got me no where !!
 

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Discussion Starter · #12 ·
2 and 12.5/24 turns on the primary for one revolution of the secondary? That would be just over 2.5:1 which is near stock...so benefit from machining.
The mechanic may have done nothing

so now I’m wondering if I can go to 1.5 mil shim , thinking upgrading to gold epi spring ,all 660 weights witch basically is 17 g weights
 

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Discussion Starter · #13 ·
So sense I think we’ve came to the conclusion the they did nothing for machining , 😡 now should I try 1.5 mil shim , gold spring , and 17 g weights ? Or just stick to 660/440 mix with purple spring and 1.5 shim ?
 

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As others have mentioned, my stock was 2.45:1 and I'm just under 3:1 with a coop45 machined sheave. No shim added

Assuming you are still stock.

Start with 1.5 mm of shims and a epi purple spring
 

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Not sharing the name of the shop does nothing to help the community. It does quite the opposite.

Wouldn't YOU like to know the names of places who's services should be avoided? I sure would...
 

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Grizzled
2014 Yamaha Grizzly 700 EPS
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@Wade1

Here are some pictures where I have a coop45 machined primary MOVEABLE sheave (left) and a Grizzly 700 OEM primary MOVEABLE sheave (right). My primary FIXED sheave is not machined as you were told yours was. There are slightly different ways to machine the primary moveable sheave face but from what I am aware of, you'll either have the large looking hump like the coop45 sheave or where that hump will be machined completely off.

100403


100404


100405


100406
 
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Looks like the new angle is wrong for better low end ratio, hard to tell in a picture.
 
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Agree with Jim that it is hard to tell. If I were to guess, the red area I circled is what was machined off, which would seem like hardly anything. The machining for low end torque is mostly near the hub. If you look at my last picture, previous post, you can see that the outside edge is the same which is what you want. The majority of the machining needs to be near the inner hub and then taper off about 1/2 way towards the outside. Did yours get machined? Kind of looks like it maybe did. Did the person who machined yours know what they were doing? $100 CDN says no. I would ask them to do a better job.

100408
 
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Here is my coop sheave vs stock.
100409
 
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