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Which clutch sheave to buy?

1207 Views 11 Replies 7 Participants Last post by  Vagabond
I am new to this site, been wheeling all my life, but never dealt with a CVT. Just bought an 05 grizzly 660, and I would like to get a clutch sheave mod to help turn my 27" tires/wheels. I have narrowed it down to Coop, JBS and airdam. I ride rocky up hills and mud, along with access roads, so I need it to be an all around quad. Can anyone help me make this decision? I can find information on each, but not much that compares all 3. Any help would be very much appreciated. I am interested in results, not arguments.. Please!
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Hey...Vagabond...Welcome to GC from Wisconsin.

Coop...by far.
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Hey...Vagabond...Welcome to GC from Wisconsin.

Coop...by far.
Thanks for the input!
I am new to this site, been wheeling all my life, but never dealt with a CVT. Just bought an 05 grizzly 660, and I would like to get a clutch sheave mod to help turn my 27" tires/wheels. I have narrowed it down to Coop, JBS and airdam. I ride rocky up hills and mud, along with access roads, so I need it to be an all around quad. Can anyone help me make this decision? I can find information on each, but not much that compares all 3. Any help would be very much appreciated. I am interested in results, not arguments.. Please!
I have the Coops sheave and purple spring installed and has made a big difference in my Grizz especially in the midrange and for towing, no regrets at all, Arnie is great to deal with also.
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Vincent, it looks like that is incompatible with my 05 660, thank you for sending the link my way though.
Have you thought about just a shim and spring mod? If top end losing a few mph isn't a big deal it is a lot cheaper with similar results. Oh and welcome to GC from Tn
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Vincent, it looks like that is incompatible with my 05 660, thank you for sending the link my way though.
My apologies for that mistake.
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Have you thought about just a shim and spring mod? If top end losing a few mph isn't a big deal it is a lot cheaper with similar results. Oh and welcome to GC from Tn
Shim should be here soon, slider weights too
For the 660, go with Coop, if your going to replace the primary sheave.
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Welcome from Colorado.
Call COOP and make arrangements to send him your movable primary sheave for machining.
As for comparisons, I'm not sure a member here has ran all 3 on one bike.
For the best bang for the buck, I found COOP the way to go. I run all the C.V.T. mods listed in the signature for the best set-up in my area which is very rocky with large vertical gains during a days ride. It is a very good overall set-up.
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Welcome from Colorado.
Call COOP and make arrangements to send him your movable primary sheave for machining.
As for comparisons, I'm not sure a member here has ran all 3 on one bike.
For the best bang for the buck, I found COOP the way to go. I run all the C.V.T. mods listed in the signature for the best set-up in my area which is very rocky with large vertical gains during a days ride. It is a very good overall set-up.

I spoke to Coop, seems like a great guy, everyone has been extremely helpful so far on the site. It seems to me that Coop's mod makes more sense, you can add a good bit more shim to his setup, giving it more ability to be adjusted. I just need to figure out when I can suck it up and deal with down time. On a side note, my skid plates have arrived!
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