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@andrewdeal12 Thanks for coming back on and providing more detail. There are still items I have questions about but I don't want it coming off as controversial like what happens on the FB Yamaha Grizzly 700 group. And talk about A LOT of misinformation, that FB group is full of it, literally, to a point that I only go on there for some laughs and head shaking. That other Grizzly 700 user group is not any better as it has many of the same people spreading misinformation where they can't engage in a reasonable conversation without, uncalled for, personal attacks... it got old real fast. I've got pretty thick skin but got tired of braindead 2-year olds acting out.

I'd be interested in learning more about the data you have but I'm not going on FB for it. Seems like if you want to explain yourself, the testing you've done and theories you've come up with, with the potential for converting some on here, this is the appropriate place to do that.
I appreciate that. I know you said you aren’t one off the Facebook groups but if you’d like to pm me on Facebook I can gladly go into a little more detail and send you some pictures of my work, I’m not trying to sell you anything I promise haha
 

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Most getting into c.v.t. mods don't realize how the theories of modifying the movable sheave face or the channels are so different causing differences in flexibility for tuning to different trail conditions. For those riding flat ground one set-up might be OK, but for me I ride from 3000ft. to 14,000ft. routinely using the same engine, transmission and final drive assemblies so rely on the ability to change the c.v.t. ratio and up-shift rate for the trail conditions of this area.

Arnie works with the kiss theory while others are focused on specifics without thought to simple flexibility.
For instance why would you machine anything (channel or face) then add taller weights to effect the ratio? Why not do 'no' machining and use shims to increase the ratio to magnify engine torque produced?
Then when the shim limit is reached and you want more of the same feel-good do machining to run in combination with shim(s)?

Here's another deal: The stock ratio when new is @ 2.5:1 and we raise the ratio (like increasing the tooth count on the rear motor cycle sprocket) with shims, or machining, or different diameter weights, or a narrow belt. I use all of these different mods in combination.
Raising the ratio is done by changing the distance between the movable sheave face and fix sheave face so the belt rides lower in the primary.
I can raise my ratio on a 660 to 3.75:1 as seen in a video I did years ago. This is not a good ratio to ride but available when the system is understood.
I ride a 3.54:1 ratio mostly with great torque magnification at take off. My Griz will jump off the line getting to 20 m.p.h. in 2 seconds and less than 30ft. and this is reliant on the angle of the stock cam-plate face in the cut cam-plate I use, the portion of the face inside the bend of the new tab.
In this set-up the higher ratio and shallower cam-plate face angle lets the engine spool up faster building engine torque so then at 20 m.p.h. the new cam-plate face angle is hit by the weight(s) for increased forward bite and lower cruising engine r.p.m.'s v the stock cam-plate face angle.

Why anyone selling c.v.t. mods would recommend not using a cut cam-plate for best performance is beyond my understanding, although I also understand most riders don't want to put in the time changing set-ups to learn their c.v.t. system choices.

Over the years I've learned Arnie's theories and installed them in my c.v.t., then recommended what I know is good to other members that installed these in their c.v.t.'s.
I eventually rode with members on the trails from Moab to 'Land Between the Lake' on the Tennessee and Cumberland Rivers and not once did another member tell me Arnie's work and my recommendations didn't work exactly like they needed for their conditions and machine set-ups.

Some members run 25" tires and other run 27" tires with me running 26"ers and there is always a combination with Arnie's machining that works.

Another thing important to remember 'IS' years ago when James joined G.C. to promote his work James made an offer that he would send his set-up to a member currently using Arnie's, willing to run his set-up against Arnie's in their machine for a report back to the members here.
I called James and he never fulfilled his offer and became know as J.B.S., 'just because I said' here on G.C.

Deal seems different than James, maybe his theory is sound. If any member here tries his work I look forward to a review.
Sorry to quote this again, touch on the shim idea, basically if you run the larger weights with shims you’re more or less just robbing Peter to pay Paul so to say ( at least the way I look at it) , the most you’d get out of it would be the bottom end equivalent of a 1mm shim on bottom end (if the way I worded that makes sense) go to a 1.5 or 2 you’re losing top speed, either way you still won’t get the quicker shift out. With the machining of the weight pockets the sheaves are pushed in quicker out of bottom end giving you the quicker shift out. We can all agree the grizzly engines are not high revving and don’t like to be revved out so taking advantage of the torque these engines make was the idea. It also keeps the cruising rpm’s very low as well. I’ve also been able to trim the top of the channel walls slightly so the cam plate doesn’t rub them which can be an issue under torque with the machined weight pockets and towers. I’ll see if I can figure out how to post up some pictures here soon
 

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Sorry to quote this again, touch on the shim idea, basically if you run the larger weights with shims you’re more or less just robbing Peter to pay Paul so to say ( at least the way I look at it) , the most you’d get out of it would be the bottom end equivalent of a 1mm shim on bottom end (if the way I worded that makes sense) go to a 1.5 or 2 you’re losing top speed, either way you still won’t get the quicker shift out. With the machining of the weight pockets the sheaves are pushed in quicker out of bottom end giving you the quicker shift out. We can all agree the grizzly engines are not high revving and don’t like to be revved out so taking advantage of the torque these engines make was the idea. It also keeps the cruising rpm’s very low as well. I’ve also been able to trim the top of the channel walls slightly so the cam plate doesn’t rub them which can be an issue under torque with the machined weight pockets and towers. I’ll see if I can figure out how to post up some pictures here soon
I would never consider using larger (taller) weights unless I wanted to retard the performance for a youngster just getting started and I didn't care if the one-way got fried. I understand your reasoning for the taller weights, but the down side is huge and there is a MUCH easier way to get the results your theory looks for. The problem you are having now is the same problem James encountered with him promoting greaseless weights which aren't the solution. A hint for you is you're working on the wrong side of the sheave for max torque magnification.

You stated you're looking for quicker shift-out, I use the term max forward bite and to get that you must get the starting ratio as high as possible and use heavier weights. Due to the cam-plate shape design the max ratio can't be reached by machining the channels only then using round weights, again that's why James offered greaseless weights that didn't solve his problem.
The Griz engine makes enough torque to be magnified so horse power is the wrong aspect for most to focus on. Max horse power is only important for top speed runs, that's why I focus on magnifying torque as I very seldom need speed over 45 m.p.h.
For me the only true need for top speed is when stepping out on a state highway as a short cut between trail heads, with speeds of 75 m.p.h. Its then the cut cam-plate really shines to cut down the time spent on the state highway.
I determined the exact place to cut the cam-plate for best forward bite to 20 m.p.h. then determined the exact amount of bend for my ratio and the elevation. At 50 m.p.h. I'm still in the high end of torque curve so I can hit the gas for acceleration if needed to transition into the horse power curve for high top end speed. I have a video showing the belt running in the pulley, you can see the belt reach full travel across the secondary then hear the r.p.m.'s rise easily when full throttle is added. I get the belt across the pulleys faster with magnified torque long before the horse power takes over.
As for the new cam-plate tabs contacting the sheave, I grind the cam-plate for relief not the sheave.

I learned the c.v.t. system mods for my 660 (700's have less space under the cover) starting with shim, but for installation progression explanation I'll start with face machining as its the one irreversible mod:
Machining done with the correct cut (and my memory is close) I got a 2.9:1 ratio with 1200 miles of belt wear, then I added the shim (I can add up to 2.5mm's) to get to a max ratio of 3.45:1. I had to gradually wear the belt into the cover above a 3.1 ratio.
Then I gradually added to the mod combinations a narrower belt and 'shorter' weights for the 3.75:1 ratio I discovered in a video previously linked. The 3.75 'is not' a ridable ratio with the cover installed yet, I never took on the project of rubbing in the belt as I would have needed to form a blister of extra material on the cover and as I was breaking axles with ease at the 3.54 ratio I decided that was enough until someone wanted to play with more. the 3.75 ratio is achievable for data at this point.

If I was considering channel machining, I would learn what the highest achievable pulley ratio is with no other mods needed in combination. I don't know the current cost of channel machining to compare with Arnie's machining, I think Arnie was around 120 bucks and may still be near that amount. To that amount I added 9 dollars with of shims, I ordered and cut my own cam-plate at 2mm's, then as I didn't need a stock one I cut the old one at 3mm's. Cam-plates are cheap.
Then I orders a set of 21 gram weights and change the covers between weight sets, yes that can be easily done. For less than 200 bucks I can set the c.v.t. up in any configuration desired for the next ride, as an example when Hammer and I did the 972 miles in 7 days, with the single day ride of 455 miles, we needed high m.p.g. so I set the ratio at 2.8:1 for 39 m.p.g. (I had to install a new fat aftermarket belt I had laying around for this ratio). Yes there was less magnified torque for the week, but when covering that amount of distance in 7 days constant speed is the focus not max instant forward bite.
All the mods listed in my signature are currently installed.....
 
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Thanks to all contributors for the info regarding these belt setups, coming from polaris there is LOTS to learn about the ultramatic system. I appreciate you guys all keeping the discussion civil and not getting the thread locked. in my years of yamaha ownership I've found MANY clutching discussions dead ended or info deleted because things got heated and a Mod/Admin had to step in and clean up. Looking forward to the future info/discussions.
 
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I would never consider using larger (taller) weights unless I wanted to retard the performance for a youngster just getting started and I didn't care if the one-way got fried. I understand your reasoning for the taller weights, but the down side is huge and there is a MUCH easier way to get the results your theory looks for. The problem you are having now is the same problem James encountered with him promoting greaseless weights which aren't the solution. A hint for you is you're working on the wrong side of the sheave for max torque magnification.

You stated you're looking for quicker shift-out, I use the term max forward bite and to get that you must get the starting ratio as high as possible and use heavier weights. Due to the cam-plate shape design the max ratio can't be reached by machining the channels only then using round weights, again that's why James offered greaseless weights that didn't solve his problem.
The Griz engine makes enough torque to be magnified so horse power is the wrong aspect for most to focus on. Max horse power is only important for top speed runs, that's why I focus on magnifying torque as I very seldom need speed over 45 m.p.h.
For me the only true need for top speed is when stepping out on a state highway as a short cut between trail heads, with speeds of 75 m.p.h. Its then the cut cam-plate really shines to cut down the time spent on the state highway.
I determined the exact place to cut the cam-plate for best forward bite to 20 m.p.h. then determined the exact amount of bend for my ratio and the elevation. At 50 m.p.h. I'm still in the high end of torque curve so I can hit the gas for acceleration if needed to transition into the horse power curve for high top end speed. I have a video showing the belt running in the pulley, you can see the belt reach full travel across the secondary then hear the r.p.m.'s rise easily when full throttle is added. I get the belt across the pulleys faster with magnified torque long before the horse power takes over.
As for the new cam-plate tabs contacting the sheave, I grind the cam-plate for relief not the sheave.

I learned the c.v.t. system mods for my 660 (700's have less space under the cover) starting with shim, but for installation progression explanation I'll start with face machining as its the one irreversible mod:
Machining done with the correct cut (and my memory is close) I got a 2.9:1 ratio with 1200 miles of belt wear, then I added the shim (I can add up to 2.5mm's) to get to a max ratio of 3.45:1. I had to gradually wear the belt into the cover above a 3.1 ratio.
Then I gradually added to the mod combinations a narrower belt and 'shorter' weights for the 3.75:1 ratio I discovered in a video previously linked. The 3.75 'is not' a ridable ratio with the cover installed yet, I never took on the project of rubbing in the belt as I would have needed to form a blister of extra material on the cover and as I was breaking axles with ease at the 3.54 ratio I decided that was enough until someone wanted to play with more. the 3.75 ratio is achievable for data at this point.

If I was considering channel machining, I would learn what the highest achievable pulley ratio is with no other mods needed in combination. I don't know the current cost of channel machining to compare with Arnie's machining, I think Arnie was around 120 bucks and may still be near that amount. To that amount I added 9 dollars with of shims, I ordered and cut my own cam-plate at 2mm's, then as I didn't need a stock one I cut the old one at 3mm's. Cam-plates are cheap.
Then I orders a set of 21 gram weights and change the covers between weight sets, yes that can be easily done. For less than 200 bucks I can set the c.v.t. up in any configuration desired for the next ride, as an example when Hammer and I did the 972 miles in 7 days, with the single day ride of 455 miles, we needed high m.p.g. so I set the ratio at 2.8:1 for 39 m.p.g. (I had to install a new fat aftermarket belt I had laying around for this ratio). Yes there was less magnified torque for the week, but when covering that amount of distance in 7 days constant speed is the focus not max instant forward bite.
All the mods listed in my signature are currently installed.....
I would never consider using larger (taller) weights unless I wanted to retard the performance for a youngster just getting started and I didn't care if the one-way got fried. I understand your reasoning for the taller weights, but the down side is huge and there is a MUCH easier way to get the results your theory looks for. The problem you are having now is the same problem James encountered with him promoting greaseless weights which aren't the solution. A hint for you is you're working on the wrong side of the sheave for max torque magnification.

You stated you're looking for quicker shift-out, I use the term max forward bite and to get that you must get the starting ratio as high as possible and use heavier weights. Due to the cam-plate shape design the max ratio can't be reached by machining the channels only then using round weights, again that's why James offered greaseless weights that didn't solve his problem.
The Griz engine makes enough torque to be magnified so horse power is the wrong aspect for most to focus on. Max horse power is only important for top speed runs, that's why I focus on magnifying torque as I very seldom need speed over 45 m.p.h.
For me the only true need for top speed is when stepping out on a state highway as a short cut between trail heads, with speeds of 75 m.p.h. Its then the cut cam-plate really shines to cut down the time spent on the state highway.
I determined the exact place to cut the cam-plate for best forward bite to 20 m.p.h. then determined the exact amount of bend for my ratio and the elevation. At 50 m.p.h. I'm still in the high end of torque curve so I can hit the gas for acceleration if needed to transition into the horse power curve for high top end speed. I have a video showing the belt running in the pulley, you can see the belt reach full travel across the secondary then hear the r.p.m.'s rise easily when full throttle is added. I get the belt across the pulleys faster with magnified torque long before the horse power takes over.
As for the new cam-plate tabs contacting the sheave, I grind the cam-plate for relief not the sheave.

I learned the c.v.t. system mods for my 660 (700's have less space under the cover) starting with shim, but for installation progression explanation I'll start with face machining as its the one irreversible mod:
Machining done with the correct cut (and my memory is close) I got a 2.9:1 ratio with 1200 miles of belt wear, then I added the shim (I can add up to 2.5mm's) to get to a max ratio of 3.45:1. I had to gradually wear the belt into the cover above a 3.1 ratio.
Then I gradually added to the mod combinations a narrower belt and 'shorter' weights for the 3.75:1 ratio I discovered in a video previously linked. The 3.75 'is not' a ridable ratio with the cover installed yet, I never took on the project of rubbing in the belt as I would have needed to form a blister of extra material on the cover and as I was breaking axles with ease at the 3.54 ratio I decided that was enough until someone wanted to play with more. the 3.75 ratio is achievable for data at this point.

If I was considering channel machining, I would learn what the highest achievable pulley ratio is with no other mods needed in combination. I don't know the current cost of channel machining to compare with Arnie's machining, I think Arnie was around 120 bucks and may still be near that amount. To that amount I added 9 dollars with of shims, I ordered and cut my own cam-plate at 2mm's, then as I didn't need a stock one I cut the old one at 3mm's. Cam-plates are cheap.
Then I orders a set of 21 gram weights and change the covers between weight sets, yes that can be easily done. For less than 200 bucks I can set the c.v.t. up in any configuration desired for the next ride, as an example when Hammer and I did the 972 miles in 7 days, with the single day ride of 455 miles, we needed high m.p.g. so I set the ratio at 2.8:1 for 39 m.p.g. (I had to install a new fat aftermarket belt I had laying around for this ratio). Yes there was less magnified torque for the week, but when covering that amount of distance in 7 days constant speed is the focus not max instant forward bite.
All the mods listed in my signature are currently installed.....
So what you were saying at the start about the taller weights is correct, the larger weights would not work properly. With my sheave I machine enough away at the bottom of the pockets that the larger weights are able sit deep enough to get a 2:9-3:1 ratio which is the maximum possible with the factory belt cover on a 700. I’ve compared this directly against a machined sheave for factory style weights as well as some other styles. There ended up being a large boost in mid range and lower cruising rpm. Keeps the engine in an rpm range where it’s happiest. I typically don’t sell weights less than 18g in my kits (Which drives me insane because I’d love to be able to manufacture a better belt cover with more clearance and make it reasonably priced haha) I’m currently doing some testing where I’ve managed to get the primary to bottom out on the fixed sheave when topped out. (I do remove the seal hump and sink the counterbore deeper) so I’m working on going farther with that (have some ideas just haven’t had time to play around much more with it) .
The cost just to have a sheave machined for factory style weights is about the same including return shipping (depends on the exchange rate that day honestly)
I do 660 kits at the moment, nothing special just a sheave machined for regular style greaseless weights. I’ve contemplated trying the larger diameter weights in the 660 sheaves but haven’t pushed it too much since I’m not sure how much interest is there sales wise I also don’t have reliable access to a 660 to test on. ( if you wanted to test this out say the word and I’ll get one set up and sent down to you to try) I’m always open to feedback and criticism.
 

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Thanks to all contributors for the info regarding these belt setups, coming from polaris there is LOTS to learn about the ultramatic system. I appreciate you guys all keeping the discussion civil and not getting the thread locked. in my years of yamaha ownership I've found MANY clutching discussions dead ended or info deleted because things got heated and a Mod/Admin had to step in and clean up. Looking forward to the future info/discussions.
I don’t want to be painted with the same brush as some other clutch guy. ( not mentioning names) , I feel some people have gotten the wrong idea about me which is unfortunate, while I greatly appreciate all of my customers, I cant always control the way people come across on social media when talking about my products good or bad . not all of it reflects how I would handle certain situations.
 

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if you wanted to test this out say the word and I’ll get one set up and sent down to you to try) I’m always open to feedback and criticism.
I sat here thinking of your offer for testing your sheave set-up on my 660 and your offer to test is admirable and almost appealing so I read your post again to understand you have too many problems ahead to sort through as you're new to understanding the Yamaha c.v.t.
I say this because of the other member with his current build thread running your sheave and another member post about nay-sayers.
This is the exact same thing that happened years ago when James showed up, he had others believing until many members bought his work to learn channel machining is not what get the most for the money spent. The result of that channel machining experience was a split with some good members going away embarrassed for their part in the argument.
I spent years learning how to get a 3.75 ratio, up from 2.5 stock, so why would I take the time to remove my preferred 3.54 ratio out to run your lower ratio? Have you found the thread were a member called out James when the channel machined sheave came apart, with the members claiming different causes for the failure? The buyer claiming failure was from machining too much material with the seller on the other side of the fence.
Again I like your offer to me, but I'm not going to remove what I have now. You can make that offer to another member with a 700 running Coop's sheave, then myself and that member can do the trial.
 

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One thing that most people don't know is the 660 primary sheave does not have a seal hump and will fit on the 700's (not 708's). No seal humps allow for a little deeper ratio without the need to machine it off or recess the seal.
I do have a lot of interest in CVT technology and possible ideas but I no longer have any interest in running a machine sheave.
For my riding I remove that nasty grreeezzze, change the rollers weights and sometimes the spring.
 
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One thing that most people don't know is the 660 primary sheave does not have a seal hump and will fit on the 700's (not 708's). No seal humps allow for a little deeper ratio without the need to machine it off or recess the seal.
I do have a lot of interest in CVT technology and possible ideas but I no longer have any interest in running a machine sheave.
For my riding I remove that nasty grreeezzze, change the rollers weights and sometimes the spring.
One thing that most people don't know is the 660 primary sheave does not have a seal hump and will fit on the 700's (not 708's). No seal humps allow for a little deeper ratio without the need to machine it off or recess the seal.
I do have a lot of interest in CVT technology and possible ideas but I no longer have any interest in running a machine sheave.
For my riding I remove that nasty grreeezzze, change the rollers weights and sometimes the spring.
What makes that sheave different that it won't fit a 708 vs a 686?
Looking up on part Zilla, that safe sheave was used since 2009 on all the 700 with exception to the 2017 & 18 years for some reason. It still shows that sheave used on the 2016 708cc engine. Now it's got me wondering what is different about the 2017 & 18.
 

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What makes that sheave different that it won't fit a 708 vs a 686?
Looking up on part Zilla, that safe sheave was used since 2009 on all the 700 with exception to the 2017 & 18 years for some reason. It still shows that sheave used on the 2016 708cc engine. Now it's got me wondering what is different about the 2017 & 18.
I edited my post as I posted the wrong info. Last fall I discovered that some WC related parts on the 708 don't crossover to the 700's

Thanks for pointing it out.
 

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Still had me curious as to what's different about the sheave on the 17 & 18.

Especially since my Kodiak is an 18, and my machined sheave is from a 14 or 15 bike. Lol
The primary sheaves are the same on all grizzlies from 07-23, the casting numbers vary but that’s it. I measured each generation of sheaves from 02-04 casting numbers and there isn’t any differences. I can run the same program on an 07 as I do one brand new sheave from Yamaha. Kodiak 700 are all the same as well. Only clutching difference is the primary weights vs the grizzly which is pretty common knowledge by now.

Wet clutch cover is different on the 708, the wet clutch itself matched up with some newer grizzlies. And the primary cage is slightly different than the 686 motor machines.
 

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Still had me curious as to what's different about the sheave on the 17 & 18.

Especially since my Kodiak is an 18, and my machined sheave is from a 14 or 15 bike. Lol
The 708 clutch housing is different. It is bass turd to the 708. Also the primary cage has a larger bearing.
660 primaries are the same as the 700s other than they do not have a seal hump.
 

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The 708 clutch housing is different. It is bass turd to the 708. Also the primary cage has a larger bearing.
660 primaries are the same as the 700s other than they do not have a seal hump.
I have had them all in front of me and measured them all. The 708 primary sheave is no different than the 686 versions, all interchangeable without any performance differences. As to why Yamaha uses a different part number for them on certain years is beyond me.
The 660 grizzly primary is different than the 700 even beyond the seal hump, the 700 primary is machined “deeper” on the face, if you try to swap a 700 primary on a 660 the belt will ride extremely high on the secondary and rub the cover. I have all of these sheave sitting on my bench as I write this.
 

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Sorry...If the stock 700 sheave is machined deeper the result would be the belt riding higher than the stock 660 sheave.
 
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