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Discussion Starter #1
I ride up and down steep hills, and I carry up to 300 pounds with me and my saws, tools, and other things. I get great engine braking, but if I don’t use my brakes, and get up to about 10 mph, I start to almost freewheel. Braking is good, at a slow speed, but it seems to go away once I get going a bit fast coming down hill.

I can deal with it, but I am curious what causes the engine breaking to lose its effectiveness at higher speeds.
 

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The nature of the beast.

Try giving it a little bit of throttle to kick the clutches back in. That is what I would do on my 2000.
 

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You may have a weak spring, or require a much stronger spring to help the cvt backshift properly. Maybe your one way bearing is slipping past 10 mph.
 

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Interesting observations and I will research that some. I don't have a good understanding on how this works. I don't think I mentioned that I always use Low range and 4x4, up and down the hills, and if I hold the speed down with the brakes, It holds back quite well. Thanks for the input and help!
 

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Interesting observations and I will research that some. I don't have a good understanding on how this works. I don't think I mentioned that I always use Low range and 4x4, up and down the hills, and if I hold the speed down with the brakes, It holds back quite well. Thanks for the input and help!
What questions do you have? I'll more then gladly try to answer any questions you may have...
Hopefully we can find an answer to your problem if one exists.

In my case my Grizzly has tremendous engine breaking in high and especially low, but my CVT has alot of mods done. ( see signature)
 

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Discussion Starter #6
I blame this on my excess weight that I carry. That is one big question. Can I have this checked under factory warranty? I can live with this, but I use a lot of brakes.

What is the one way bearing?

I have one more question also. If I am using excess brakes, should I concentrate on using the front brakes, as they seem like they will be easy to replace, compared to the rear brakes?

And thanks a bunch for the answers to you and JimP
 

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Try the adding a little throttle trick the next time it happens.

I learned it from riding snow machines to slow down going downhill

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Try the adding a little throttle trick the next time it happens.

I learned it from riding snow machines to slow down going downhill

Sent from my SM-J737V using Tapatalk

Worth a try but probably won't work on a constant belt tension system like our Grizzly / Kodiak utilize.

But it does work on my Yamaha 700 triple Venture Snowmobile and all other snowmobiles as well as , Can Am, Kawasaki, and Polaris Atvs as they all utilities the same non constant belt tension cvt systems. These systems often need the engine to be reved up a bit to get the primary sheave to close and clamp down on the belt to transmit wheel / track momentom to the Engine while decelerating.
 

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I blame this on my excess weight that I carry. That is one big question. Can I have this checked under factory warranty? I can live with this, but I use a lot of brakes.

What is the one way bearing?

I have one more question also. If I am using excess brakes, should I concentrate on using the front brakes, as they seem like they will be easy to replace, compared to the rear brakes?

And thanks a bunch for the answers to you and JimP
One way bearing or sprag clutch is secured in your wet clutch drum but rides on your wet clutch / crankshaft assembly shaft. As the motor revs up to about 1800 rpms the wet clutch shoes are moved out by centrifugal force and start grabbed the drum witch turns your primary sheave. At this moment the wet clutch ( sprag clutch) simply slides on the wet clutch / crankshaft shaft. But as you release the throttle the
cam shape steel wedges of the sprag clutch "bite" onto the wet clutch / crankshaft assembly witch transmits all the wheels rotating momentum to your your crankshaft and the engine's compression slows the bike down. Without a properly working one way bearing your bike will tend to free wheel, every time you let off the throttle.

This is a photo of my bike but yours is the exact same. You can see the one way bearing (sprag clutch) in the drum. Also you can see the wet assembly / shoes secured on the crankshaft as well as the surface area the sprag clutch slides / bites on.
 

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At 10mph the clutches are starting to shift to a higher ratio which works against engine braking. On VERY steep hills mine start to pick up speed slowly until the engine sound like its near red line and then really starts gathering speed. On my Rancher 420 you could possibly blow the engine in a situation like this as it wouldn't shift to 2nd to protect itself on its own. I think you just found the limits of how much the engine can slow you down. The same shim/machined clutch that raises the clutch ratio to ~3:1 would also help reducing the initial gear ratio.
 

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Worth a try but probably won't work on a constant belt tension system like our Grizzly / Kodiak utilize.

But it does work on my Yamaha 700 triple Venture Snowmobile and all other snowmobiles as well as , Can Am, Kawasaki, and Polaris Atvs as they all utilities the same non constant belt tension cvt systems. These systems often need the engine to be reved up a bit to get the primary sheave to close and clamp down on the belt to transmit wheel / track momentom to the Engine while decelerating.

It worked on my 2000 Kodiak, I am pretty sure that it was the same type of system on it.
 

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Discussion Starter #12
Wow, lots of very good info. I am going to play with this a bit and see what I can observe. I can't imagine getting a complete answer from anyone at the dealership on this. Thanks for all the input.
 

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,it worked on my 2000 Kodiak. I am pretty sure that it was the same type of system on it.
Nope

I did a full service on a 2000 Kodiak ( both primary and secondary sheaves were completely disassemble) . All Yamaha automatic atv utilize the same style of constant belt tension system.

I also drove that atv for 100 kms, and it functioned in the same fashion as my own Grizzly.

Can't comment on why your atv needed throttle to slow down as obviously I wasn't there, but I certainly will take your word for it.

I've driven many Yamaha's and I've never experienced. Yet anyways......
 

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Another quick thought, the Stock 30g clutch roller are probably also working against engine braking since they start to shift out the primary at only 3000rpm Vs. 4000rpm with the Grizzly weights. Next ride out I'll go try the steep hill that makes mine eventually pick up speed and see if the 20g weights I installed help maintain engine braking longer or not.
 

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Another quick thought, the Stock 30g clutch roller are probably also working against engine braking since they start to shift out the primary at only 3000rpm Vs. 4000rpm with the Grizzly weights. Next ride out I'll go try the steep hill that makes mine eventually pick up speed and see if the 20g weights I installed help maintain engine braking longer or not.
That is certainly another major consideration. I was thinking of that too, but I don't own a 700 kodiak so I didn't want to bring it up because of my own lack of experience with such heavy weights.
 

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Nope

I did a full service on a 2000 Kodiak ( both primary and secondary sheaves were completely disassemble) . All Yamaha automatic atv utilize the same style of constant belt tension system.

I also drove that atv for 100 kms, and it functioned in the same fashion as my own Grizzly.

Can't comment on why your atv needed throttle to slow down as obviously I wasn't there, but I certainly will take your word for it.

I've driven many Yamaha's and I've never experienced. Yet anyways......
You didn't have to do it all the time. If the hill was short enough the engine brake would work just fine. But on a longer hill you could hear it start to freewheel and then just a touch of throttle would engage the belt tension and I would be fine until it did it again.
 

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I was thinking it might be something similar to what BlueIronRanger said, that at faster speeds the cvt is switching to a higher gear ratio and the engine break is less effective. Hopefully you don't have to break into it as deep as Vincent was just showing.
 

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I was thinking it might be something similar to what BlueIronRanger said, that at faster speeds the cvt is switching to a higher gear ratio and the engine break is less effective. Hopefully you don't have to break into it as deep as Vincent was just showing.
For sure. Like I said, I've never experienced the kodiak 700 heavy weights and shitting carotiristics. So there is certainly some truth that his bike may be behaving normally

I've racked up alot of miles on my buddies 09 700 Grizzly witch utilizes the exact same spring and cvt components as the all 700 kodiaks. The only exception his Grizzly came with 21g weight factory stock. His bike has zero cvt mods and is 100% stock other then 27" tires. Driving his bike is very similar to driving mine as fare as breaks and engine braking etc.....In low range 4wd drive, we both don't need much brake force to maintain a steady speed going down steep hills.
 

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Discussion Starter #19
Again lots of good info and thoughts. I will see how things react when I am coasting down hill, and play with the throttle a bit. Here is one thing I can tell you that I had not done before. I let it go when the engine braking released it seemed to have no limit to how fast it was willing to go on a straight stretch. I fear the consequences if something engaged as I reach 30 mph in low range. Engine RPM is slow at this point.
 

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Again lots of good info and thoughts. I will see how things react when I am coasting down hill, and play with the throttle a bit. Here is one thing I can tell you that I had not done before. I let it go when the engine braking released it seemed to have no limit to how fast it was willing to go on a straight stretch. I fear the consequences if something engaged as I reach 30 mph in low range. Engine RPM is slow at this point.
Shouldn't be any issues driving up to 40 mph in Low range , I've done that many times. Just revs more, and engine braking is much stronger. Just be aware.....
 
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