Yamaha Grizzly ATV Forum banner
1 - 20 of 29 Posts

·
Registered
Joined
·
59 Posts
Discussion Starter · #1 ·
Hey all, I have a 2021 grizzly 700 and I already have 1.5mm shims in and purple spring, I ordered the EPI sport utility clutch kit and was wondering if anyone has had any belt slippage or issues with this set up ? I was debating taking the shims out cause it could possibly cause belt slippage with the clutch kit. I’m running 26 ITP Mud lights but intend to go to 27s.
 

·
Registered
Joined
·
2,773 Posts
If you already have the shims and a purple spring, why order an epi clutch kit? What are you looking to gain from what you have now?
 
  • Like
Reactions: Travis 2021 Grizzly

·
Registered
Joined
·
59 Posts
Discussion Starter · #3 ·
I have a buddy that recommended the clutch kit but doesn’t seem to recommend the shims to go along with it. I’m after lots of torque and pep don’t care for top speed. (Make up for heavy tires and two up) I do a lot of trail riding two up and my trails tend to get muddy but I’m not into hardcore mudding just sometimes can’t avoid it. From what I’ve read the clutch kit will increase my clutch engagement and the shims I know give you more low end torque with loss of top speed. I enjoy the increased low end in high gear the shims give. Does the clutch kit act the same as adding the shims ? Sorry green horn with all of this stuff !
 

·
Registered
Joined
·
2,773 Posts
I have a buddy that recommended the clutch kit but doesn’t seem to recommend the shims to go along with it. I’m after lots of torque and pep don’t care for top speed. (Make up for heavy tires and two up) I do a lot of trail riding two up and my trails tend to get muddy but I’m not into hardcore mudding just sometimes can’t avoid it. From what I’ve read the clutch kit will increase my clutch engagement and the shims I know give you more low end torque with loss of top speed. I enjoy the increased low end in high gear the shims give. Does the clutch kit act the same as adding the shims ? Sorry green horn with all of this stuff !
The epi clutch kits don t do anything to increase the initial low end torque. Shims on the other hand to exactly that. They start you in a lower gear sorta speak

They epi kits also generally come with stall springs which bring up the wet clutch engagment , this is ment to give more off the line snap but also has a tendency to burn up the wet clutch which is a bad thing..

Most on this forum will suggest you stay away from the EPI kits as they are over priced ...

What you chose is up to you, but bang for buck the shims and purple spring is already a good start.

If you want more low end torque , a coop machined sheave is the next step in my and many others opinion.
 

·
Registered
Joined
·
59 Posts
Discussion Starter · #5 ·
So you wouldn’t recommend mixing the the shims with that EPI clutch kit ? I looked into the Mod #3 but I found it was pricey and the I got the EPI clutch kit for a decent price.
 

·
Registered
Joined
·
2,773 Posts
So you wouldn’t recommend mixing the the shims with that EPI clutch kit ? I looked into the Mod #3 but I found it was pricey and the I got the EPI clutch kit for a decent price.
If you want to experiment a little and mix and match give her a shot, and report back your finding. It s your machine so do what makes you happy.
 
  • Like
Reactions: Travis 2021 Grizzly

·
Premium Member
Joined
·
12,259 Posts
The E.P.I. kit you ordered is worthless for what you want, the shim raises the pulley ratio which magnifies/multiplies the torque produced so.....
The COOP machined primary movable sheave is like adding shim, it raises the pulley ratio and magnifies/multiplies the torque even more.
Look in my signature for the c.v.t. mods I run, I raised the pulley ratio to the max, then added other mods for increased forward bite and higher m.p.g.
 
  • Like
Reactions: Travis 2021 Grizzly

·
Premium Member
Joined
·
12,259 Posts
You wouldn’t even recommend trying it? I could probably try to return it, guess I shouldn’t have listened to my buddy !
:)
We are trying to save you the time (wasted time) of installing the kit for nothing you want.
The kits are for those that are looking for better but don't know/understand how the c.v.t. system works. I say work, as each part in the system effects the other parts in the system, its a relationship deal and.....
The deal 'IS' a high pulley ratio is great for out of the hole pull...and COOP was the first to offer Mod 1, the shim mod. As time when on members wanted more from their systems and COOP realized the linear effect of shim so worked on another part in the system, the cam-plate.
His mod #2 is a cut cam-plate which leaves the ramp angle the same at the bottom ( the stock angle) and his bend starts part way up the ramp so the shim effect is felt at take off, then as the weights hit the new ramp angle from mod #2 under greater force, the shim mod effect is reduced to restore the top speed lose from the shim mod.
E.P.I. sells to those that don't understand the Yamaha c.v.t. system, if we can help let us know.
 

·
Registered
Joined
·
2,773 Posts
You wouldn’t even recommend trying it? I could probably try to return it, guess I shouldn’t have listened to my buddy !
Probably not....lol

Why did he advise you against using shims?
 
  • Like
Reactions: Travis 2021 Grizzly

·
Registered
Joined
·
1,129 Posts
Return that epi kit, use that money towards a coop mod 3. You will be much happier. Those kids are a waste of money, not to mention, you can purchase all parts of the kit separately for less than the kit.
But that kit is not what you are looking for. Go with the shims and the purple spring, and direct you buddy to these forums and google to educate himself on cvt systems.

Sent from my Pixel 5 using Tapatalk
 

·
Registered
Joined
·
59 Posts
Discussion Starter · #14 ·
He has an EPI clutch kit installed and likes it’s a lot, he has nothing against the shims but thinks it will cause belt slippage from the primary engagement if I run the shims and the clutch kit. I was looking at returning the kit but I opened it to see what colour spring it came with (cut the sticker seal) so not sure they will take it back.
 

·
Registered
Joined
·
2,773 Posts
He has an EPI clutch kit installed and likes it’s a lot, he has nothing against the shims but thinks it will cause belt slippage from the primary engagement if I run the shims and the clutch kit. I was looking at returning the kit but I opened it to see what colour spring it came with (cut the sticker seal) so not sure they will take it back.
Personnaly I m super impressed how tuned the clutching is on 2019 grizzly right from the factory.

The only thing i changed is my movable primary sheave is a coop machined sheave which I had on my privious grizzly.

My initial cvt ratio is 2.95:1 vs stock 2.45:1....Still running stock weights and spring. It turns my heavy Growlers tires with authority . I ve racked up 3800kms on this set up

I did try the purple spring early on but found the extra reving while accelerating normally was annoying. 3 days later, I went back to stock spring, and never looked back.
 

·
Premium Member
Joined
·
839 Posts
Kind of a crappy return policy if you just opened it and didn't install.
I have a 2021 as well with a Coop Mod#3 and a shim. I like bottom end. I still can run 60mph, although I don't do that very often. When you get the Coop sheave it's like adding somewhere around 3mm of shim due to his machining. Well worth the money spent for bottom end power. I mailed mine (sheave) to him and was back in less than a week. Just call and talk to him, he's a great guy and extremely knowledgeable. I had his Mod#3 on my 2013 and put over 8000 miles trouble free and was great. I did put in a purple spring (2013 &2021) to help me with backshifiting and engine braking. But that was only around $35 for the Spring.
 
  • Like
Reactions: Travis 2021 Grizzly

·
Registered
Joined
·
69 Posts
Personnaly I m super impressed how tuned the clutching is on 2019 grizzly right from the factory.

The only thing i changed is my movable primary sheave is a coop machined sheave which I had on my privious grizzly.

My initial cvt ratio is 2.95:1 vs stock 2.45:1....Still running stock weights and spring. It turns my heavy Growlers tires with authority . I ve racked up 3800kms on this set up

I did try the purple spring early on but found the extra reving while accelerating normally was annoying. 3 days later, I went back to stock spring, and never looked back.
Although I’m still on stock Zilla’s, I completely agree! Even at lower speeds with stock sheave it’s very well mannered. Much better response than the Kodiak, even with its mods.
 

·
Registered
Joined
·
59 Posts
Discussion Starter · #19 ·
Kind of a crappy return policy if you just opened it and didn't install.
I have a 2021 as well with a Coop Mod#3 and a shim. I like bottom end. I still can run 60mph, although I don't do that very often. When you get the Coop sheave it's like adding somewhere around 3mm of shim due to his machining. Well worth the money spent for bottom end power. I mailed mine (sheave) to him and was back in less than a week. Just call and talk to him, he's a great guy and extremely knowledgeable. I had his Mod#3 on my 2013 and put over 8000 miles trouble free and was great. I did put in a purple spring (2013 &2021) to help me with backshifiting and engine braking. But that was only around $35 for the Spring.
I priced out a new sheave from him and it’s close to $500 Canadian bit pricey for me right now, I don’t want to send my sheave in cause I don’t want any down time before winter, I rip weekends and after work during the week so.
 

·
Registered
Joined
·
2,773 Posts
I priced out a new sheave from him and it’s close to $500 Canadian bit pricey for me right now, I don’t want to send my sheave in cause I don’t want any down time before winter, I rip weekends and after work during the week so.
That is pricey.

When i sent out my sheave to Arnie Cooper in late 2018 cost of machining , exchange and round trip shipping from my home in Northern Ontario came up to 320$ total.
 
  • Like
Reactions: Travis 2021 Grizzly
1 - 20 of 29 Posts
Top