I've given my thoughts\experiences on this on multiple occasions and instead of responding to all those individual threads I feel the issue deserves its own thread.
Let me first start off by saying that this isn't a Hunterworks-approved thread. Despite attempts by James\Timmy from JBS trying to spread misinformation, Todd and I are indeed two distinct and separate human beings. I don't own any part of Hunterworks, don't have a vested interested it, and my only compensation is that I get his sheave setup for free along with the Gear\Tranny\Engine Butter treatments along with Tinkseal (well the latter is free from Michael who's responsible for making these products) in return for testing. The only other benefit I get is peace of mind that I'm supporting an individual with the highest morals and standards. If Hunterworks were to stop supporting Yamaha products, you would not see me jump ship to JBS, simply because it is the most unethical and unprofessional business I've ever had the displeasure of dealing with. I would beg Weller Racing or any other aftermarket business to jump in the game instead.
Likewise, Michael and I are also two separate distinct individuals despite false accusations, once-again, by JBS spreading lies that we are one and the same. Some of you have actually met me, know where I live, or know Todd, knows where he lives, and maybe have met him. I have a VERY PUBLIC FB profile due to my previous drone racing business and even the most unskilled investigators can verify this. With all this being said, Todd, Michael, and I have different opinions on certain things, and you won't see the sickening love fest and parroting that James\Timmy have because Timmy's knowledge of things is severely lacking, so he simply regurgitates what James feeds him because he doesn't know any better.
I paid full retail for my X4 and as you can see from my mileage posts, I have a vested interest in making it last as long as possible. Todd or Michael aren't buying me a new engine, or new X4 if their products fail me, so if I didn't believe their products were in my best interest, I wouldn't be using them.
Greased vs greaseless. Why run grease in the primary sheave? Suzuki, Arctic Cat, and many snowmobile CVTs using the same roller\cam plate design don't use grease, nor do the scooters\mopeds that also use this same basic CVT design. They don't use special coatings or even heat-treated rollers, so if you're going to make that argument that it's used for lubrication, please explain why all these other common CVT setups don't use it.
This is my buddy's Arctic Cat 400 four wheeler that I serviced the CVT on a few months back. No grease cover and thus no grease.
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When I serviced this sheave I essentially just had to blow out the dust inside of it. Not large-grained dirt, dust. When I had my Rhino, Viking, and now my X4, the experience has been the same. I've never seen anything BUT very fine dust in my primary sliding sheave. NEVER any large-grained dirt.
Why doesn't Yamaha use an air filter on their CVT? Can Am does, Polaris does, why not Yamaha? I think we can dispel the notion that dirt attacks the sheave surfaces or belt. Unless you are a u boat commander, your sheave surfaces should look very good and in previous generations last the life of the vehicle. Those slipper clutch systems have a lot of metal-on-metal contact which dirt could accelerate wear and they need to be blown out periodically. All the metal-on-metal contact points in a Yamaha CVT are protected by grease seals and lubricated by grease...........with the exception of the primary sheave, which is open to the air.........why is that?
If you look at the design on the Yamaha CVT, it hasn't changed a whole lot, only changed in dimension and size of the components. Same goes for the cooling. You have a single cooling intake duct that Y's off, one side going to the back of the non sliding primary sheave and the other half cooling the non sliding secondary sheave (side opposite the spring). You have cooling fins on each of the non-sliding halves of each sheave which moves a decent amount of air. Each side of the belt is getting cooling from the opposing sheaves. As we all know, heat kills belts.
Notice the front quadrant of the bearing support cage is shielded. I don't think this is for structural purposes
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I think this is done purposely to help block air from getting inside the primary sheave. The grease inside a stock primary displaces air getting inside of it and it will generally last a thousands miles before it become contaminated enough to change it out. The fact that only fine dust accumulates in there shows the fact that the CVT air flow does a good job of keeping air and consequently dirt away from that area.
Primary cam plate sticking and not moving smoothly. There are two issues that can cause this. One is fixed and shouldn't be a problem on any gen with Hunterworks. It was discovered that there were OEM machining\casting inconsistencies on the cam plate towers that would cause binding of the cam plate and poor sheave performance. Owners would see this in stock setups. HW machined the towers on Gen 1 sheaves and discovered Yamaha didn't learn from its mistakes and the X2/X4 sheave also had these issues so all sheaves now get the towers milled. The second issue, which is the whole point of this thread is dust getting into the primary and causing the rollers and/or cam plate to bind up.
With Gen 1 vehicles, you could go a decent amount of time before having to blow out your primary, in my case between 1500-2000 miles. If you're a follower and not leading the pack, your primary may get filled with dust more quickly and you would have to blow it out more often. Todd NEVER advertised that going greaseless was maintenance free and your primary would have to be blown out at regular intervals. Blowing out your primary with it on the vehicle is much easier than removing your sheave to regrease it. Let's not forget the main advantage to going greaseless is that if you're not snorkeled, and swamp your CVT playing U-boat commander, you can simply wash out the mud, spin dry, and keep going vs using grease where the rest of your riding day is ruined.
So why are we seeing SOME complaints with SOME X2\X4 owners having issues within 100 miles and needing to clean their primary out vs being able to go 1000 miles like on previous generations?
Let's first address Gen 1 vs X2/X4 clutching issues\differences between each bone stock:
Gen 1 Wolverine weighs roughly 1311 lbs
2020 Wolverine X4 XTR weighs 1739 lbs
An X2/X4 makes 50% more torque than a Gen 1
The secondary spring of an Gen 1 vs X2/X4 (the larger spring at the top is the X2/X4's)
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So, we have 400 lbs more weight, at least 50% more HP if you haven't done any mods, and a secondary spring that produces way more pressure. We may also have 4 passengers with the X4 instead of 2 and we're running larger tires to boot.
We are still using the same primary rollers and same secondary cup design (pins and thickness of the metal used, not actual diameter). Guess what's failing? Guess what I experienced failing VERY EARLY ON in my 10K mile journey? Flat spotted OEM rollers IN OEM GREASE ON IN A STOCK CVT. Gouged secondary spring cup. While I was the only one to experience these issues at 3K miles, we are now seeing that these problems are no longer unique to me and MANY others are seeing the same issues: flat spotted rollers IN OEM GREASE IN BONE STOCK SHEAVE SETUPS and destroyed secondary spring cups (resulting in expensive destroyed secondary sheaves if not caught early).
SO the picture I'm trying to paint for you here is that these reused parts from the Gen 1 haven't been beefed up and are failing because of the added stress, NAMELY pressure. The reason why we're seeing flat-spotted rollers in the X2/X4 where we didn't see it in Gen 1' is because the pressure these rollers are under from the AT LEAST 400 lbs of extra weight, 50% more HP, MASSIVE OVERKILL secondary spring are all taking their toll. No discrimination here. You're going to see it on OEM weights, HV weights, and OD weights. No weight on the market today is going to be immune, just one may will wear out faster than the other.
So what's this have to do with dust? Well since there's A TON more pressure exerting on those rollers, it's compacting that dust so it sticks. In Gen 1, with the lower pressure, the rollers slid through it more easily. Since it wasn't being compacted, more dust wouldn't affect performance until you got a lot in there and it had no where to go\displace so it would get compacted and had to be blown out eventually.
Roller side loading. While the previous forces affect this, acceleration greatly affects this. What I'm talking about is the roller being pressed against one side of the roller channel under acceleration. With the X2/X4, HV AND OD weights have a disadvantage here compared to OEM weights which are hollow. HV and OD weights have more surface area and thus more friction side loading (greased or greaseless). With dust trapped between the roller side and channel wall you'll get that dust compacting under heavy acceleration. If you ease on the throttle vs slamming it, I'm betting the rollers will slide out easier when there's too much dust.
So what are some solutions\recommendations\trends?
-Don't ASSUME that some of the guys who do have issues within 100 miles are going to be indicative of everyone. I typically go 500 miles before I have to blow my sheave out
-If you don't do any high speed riding, you may accumulate dust much quicker. I get at least 10 good miles of 30-45 MPH on the highway driving both to and from the trailhead, so my sheave gets high air flow to help blow out the fine dust.
-GET THE AIR BLOWOUT PORT. Tell Todd you would like him to carry it. If 90% of his Yamaha customers request it, maybe he'll start carrying it vs having to order it separately. It makes cleaning out your primary painless. I'm going to relocate my hose to the front of the vehicle like InfidelMT did so I can blow it out while in the driver's seat. This should be the easiest solution for most users as it literally only takes minutes to do. For those of you complaining you see the problem within 100 miles, carry a portable air compressor or I'm even looking at getting a 1-2 gallon air tank.
-Run grease if you have to.
If we can get regular air flow to the primary, it could eliminate having to blow it out altogether:
-Modify the bearing support cage and remove that front section, between the frame blocking air from getting to the primary and maybe add an air re-director to force air coming of the secondary fins to the primary cavity. Yamaha did design the CVT to route air away from that area, we need to redesign it to get air to that area so fine dust doesn't have a chance to settle and accumulate there.
-Add some means of getting air there via taking the stock grease cover and stamping it so fins are created. Same thing could be done to he cam plate although it's thicker and would be harder to modify.
-Modify the CVT cover and air ducting so air is directed to the secondary via a T in the air duct feeding the secondary sheave
Dilligaf wanted to put a frog-skin type of filter on the CVT intake duct. I'm a little leary of this due to reduced cooing but it's an option to consider.
Let me first start off by saying that this isn't a Hunterworks-approved thread. Despite attempts by James\Timmy from JBS trying to spread misinformation, Todd and I are indeed two distinct and separate human beings. I don't own any part of Hunterworks, don't have a vested interested it, and my only compensation is that I get his sheave setup for free along with the Gear\Tranny\Engine Butter treatments along with Tinkseal (well the latter is free from Michael who's responsible for making these products) in return for testing. The only other benefit I get is peace of mind that I'm supporting an individual with the highest morals and standards. If Hunterworks were to stop supporting Yamaha products, you would not see me jump ship to JBS, simply because it is the most unethical and unprofessional business I've ever had the displeasure of dealing with. I would beg Weller Racing or any other aftermarket business to jump in the game instead.
Likewise, Michael and I are also two separate distinct individuals despite false accusations, once-again, by JBS spreading lies that we are one and the same. Some of you have actually met me, know where I live, or know Todd, knows where he lives, and maybe have met him. I have a VERY PUBLIC FB profile due to my previous drone racing business and even the most unskilled investigators can verify this. With all this being said, Todd, Michael, and I have different opinions on certain things, and you won't see the sickening love fest and parroting that James\Timmy have because Timmy's knowledge of things is severely lacking, so he simply regurgitates what James feeds him because he doesn't know any better.
I paid full retail for my X4 and as you can see from my mileage posts, I have a vested interest in making it last as long as possible. Todd or Michael aren't buying me a new engine, or new X4 if their products fail me, so if I didn't believe their products were in my best interest, I wouldn't be using them.
Greased vs greaseless. Why run grease in the primary sheave? Suzuki, Arctic Cat, and many snowmobile CVTs using the same roller\cam plate design don't use grease, nor do the scooters\mopeds that also use this same basic CVT design. They don't use special coatings or even heat-treated rollers, so if you're going to make that argument that it's used for lubrication, please explain why all these other common CVT setups don't use it.
This is my buddy's Arctic Cat 400 four wheeler that I serviced the CVT on a few months back. No grease cover and thus no grease.
When I serviced this sheave I essentially just had to blow out the dust inside of it. Not large-grained dirt, dust. When I had my Rhino, Viking, and now my X4, the experience has been the same. I've never seen anything BUT very fine dust in my primary sliding sheave. NEVER any large-grained dirt.
Why doesn't Yamaha use an air filter on their CVT? Can Am does, Polaris does, why not Yamaha? I think we can dispel the notion that dirt attacks the sheave surfaces or belt. Unless you are a u boat commander, your sheave surfaces should look very good and in previous generations last the life of the vehicle. Those slipper clutch systems have a lot of metal-on-metal contact which dirt could accelerate wear and they need to be blown out periodically. All the metal-on-metal contact points in a Yamaha CVT are protected by grease seals and lubricated by grease...........with the exception of the primary sheave, which is open to the air.........why is that?
If you look at the design on the Yamaha CVT, it hasn't changed a whole lot, only changed in dimension and size of the components. Same goes for the cooling. You have a single cooling intake duct that Y's off, one side going to the back of the non sliding primary sheave and the other half cooling the non sliding secondary sheave (side opposite the spring). You have cooling fins on each of the non-sliding halves of each sheave which moves a decent amount of air. Each side of the belt is getting cooling from the opposing sheaves. As we all know, heat kills belts.
Notice the front quadrant of the bearing support cage is shielded. I don't think this is for structural purposes
I think this is done purposely to help block air from getting inside the primary sheave. The grease inside a stock primary displaces air getting inside of it and it will generally last a thousands miles before it become contaminated enough to change it out. The fact that only fine dust accumulates in there shows the fact that the CVT air flow does a good job of keeping air and consequently dirt away from that area.
Primary cam plate sticking and not moving smoothly. There are two issues that can cause this. One is fixed and shouldn't be a problem on any gen with Hunterworks. It was discovered that there were OEM machining\casting inconsistencies on the cam plate towers that would cause binding of the cam plate and poor sheave performance. Owners would see this in stock setups. HW machined the towers on Gen 1 sheaves and discovered Yamaha didn't learn from its mistakes and the X2/X4 sheave also had these issues so all sheaves now get the towers milled. The second issue, which is the whole point of this thread is dust getting into the primary and causing the rollers and/or cam plate to bind up.
With Gen 1 vehicles, you could go a decent amount of time before having to blow out your primary, in my case between 1500-2000 miles. If you're a follower and not leading the pack, your primary may get filled with dust more quickly and you would have to blow it out more often. Todd NEVER advertised that going greaseless was maintenance free and your primary would have to be blown out at regular intervals. Blowing out your primary with it on the vehicle is much easier than removing your sheave to regrease it. Let's not forget the main advantage to going greaseless is that if you're not snorkeled, and swamp your CVT playing U-boat commander, you can simply wash out the mud, spin dry, and keep going vs using grease where the rest of your riding day is ruined.
So why are we seeing SOME complaints with SOME X2\X4 owners having issues within 100 miles and needing to clean their primary out vs being able to go 1000 miles like on previous generations?
Let's first address Gen 1 vs X2/X4 clutching issues\differences between each bone stock:
Gen 1 Wolverine weighs roughly 1311 lbs
2020 Wolverine X4 XTR weighs 1739 lbs
An X2/X4 makes 50% more torque than a Gen 1
The secondary spring of an Gen 1 vs X2/X4 (the larger spring at the top is the X2/X4's)
So, we have 400 lbs more weight, at least 50% more HP if you haven't done any mods, and a secondary spring that produces way more pressure. We may also have 4 passengers with the X4 instead of 2 and we're running larger tires to boot.
We are still using the same primary rollers and same secondary cup design (pins and thickness of the metal used, not actual diameter). Guess what's failing? Guess what I experienced failing VERY EARLY ON in my 10K mile journey? Flat spotted OEM rollers IN OEM GREASE ON IN A STOCK CVT. Gouged secondary spring cup. While I was the only one to experience these issues at 3K miles, we are now seeing that these problems are no longer unique to me and MANY others are seeing the same issues: flat spotted rollers IN OEM GREASE IN BONE STOCK SHEAVE SETUPS and destroyed secondary spring cups (resulting in expensive destroyed secondary sheaves if not caught early).
SO the picture I'm trying to paint for you here is that these reused parts from the Gen 1 haven't been beefed up and are failing because of the added stress, NAMELY pressure. The reason why we're seeing flat-spotted rollers in the X2/X4 where we didn't see it in Gen 1' is because the pressure these rollers are under from the AT LEAST 400 lbs of extra weight, 50% more HP, MASSIVE OVERKILL secondary spring are all taking their toll. No discrimination here. You're going to see it on OEM weights, HV weights, and OD weights. No weight on the market today is going to be immune, just one may will wear out faster than the other.
So what's this have to do with dust? Well since there's A TON more pressure exerting on those rollers, it's compacting that dust so it sticks. In Gen 1, with the lower pressure, the rollers slid through it more easily. Since it wasn't being compacted, more dust wouldn't affect performance until you got a lot in there and it had no where to go\displace so it would get compacted and had to be blown out eventually.
Roller side loading. While the previous forces affect this, acceleration greatly affects this. What I'm talking about is the roller being pressed against one side of the roller channel under acceleration. With the X2/X4, HV AND OD weights have a disadvantage here compared to OEM weights which are hollow. HV and OD weights have more surface area and thus more friction side loading (greased or greaseless). With dust trapped between the roller side and channel wall you'll get that dust compacting under heavy acceleration. If you ease on the throttle vs slamming it, I'm betting the rollers will slide out easier when there's too much dust.
So what are some solutions\recommendations\trends?
-Don't ASSUME that some of the guys who do have issues within 100 miles are going to be indicative of everyone. I typically go 500 miles before I have to blow my sheave out
-If you don't do any high speed riding, you may accumulate dust much quicker. I get at least 10 good miles of 30-45 MPH on the highway driving both to and from the trailhead, so my sheave gets high air flow to help blow out the fine dust.
-GET THE AIR BLOWOUT PORT. Tell Todd you would like him to carry it. If 90% of his Yamaha customers request it, maybe he'll start carrying it vs having to order it separately. It makes cleaning out your primary painless. I'm going to relocate my hose to the front of the vehicle like InfidelMT did so I can blow it out while in the driver's seat. This should be the easiest solution for most users as it literally only takes minutes to do. For those of you complaining you see the problem within 100 miles, carry a portable air compressor or I'm even looking at getting a 1-2 gallon air tank.
-Run grease if you have to.
If we can get regular air flow to the primary, it could eliminate having to blow it out altogether:
-Modify the bearing support cage and remove that front section, between the frame blocking air from getting to the primary and maybe add an air re-director to force air coming of the secondary fins to the primary cavity. Yamaha did design the CVT to route air away from that area, we need to redesign it to get air to that area so fine dust doesn't have a chance to settle and accumulate there.
-Add some means of getting air there via taking the stock grease cover and stamping it so fins are created. Same thing could be done to he cam plate although it's thicker and would be harder to modify.
-Modify the CVT cover and air ducting so air is directed to the secondary via a T in the air duct feeding the secondary sheave
Dilligaf wanted to put a frog-skin type of filter on the CVT intake duct. I'm a little leary of this due to reduced cooing but it's an option to consider.
