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Discussion Starter · #1 ·
Well as some of you know I traded in my wifes 17 Honda for a new 19 Kodiak 450 SE. Now that she has a couple hundred miles on it she said it needs some thing done with the clutchs as its kinda a dog down low. So today I had it on the hoist and was changing the gear lube in the front and rear differentials, cleaned the air filter, and other normal maintenance stuff with a new machine. (I already had changed the oil & filter at 143 miles) When I was done with that it was time to pull off the clutch cover and see what it looked liked.

The first thing I did was counted the clutch ratio and it was a little better then I anticipated at 2.7 to 1. So here is a few pics of whats under the cover of a 450. More to follow.
 

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Keep it coming.
 

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So others know, add shim to find the limit and what the limit is...the spline or the cage being rubbed by the cover screws.
 

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Discussion Starter · #4 · (Edited)
So others know, add shim to find the limit and what the limit is...the spline or the cage being rubbed by the cover screws.

I will have to see if I can find some shorter bolts for the cage as the bolts that holds the outside cover on also hold the cage on. I cant say I overly like the way the cage bolts up but once bolted up its like all the 700's. I have shims so I will take a look and see how much I can get and still have full cam plate engagement.
 

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Discussion Starter · #5 ·
Here is a few more pics. I thought I took a pic of the OD of the movable sheave but it was of the fixed sheave. I will get one of the movable sheave. The belt sat about 1/64" above the secondary when I took it apart.
 

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Discussion Starter · #6 ·
Well I was just getting started on this morning when my boy called and asked for help so it will have to wait till later today or tomorrow. But I did get a pic of the movable sheave OD.
 

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Discussion Starter · #7 ·
I did get far enough this morning to check out what the max shim you can put in it. You can get 1.5mm of shim and still get full engagement of the splines barely but the problem is now the washer will not have any thing to center on when you go to put the nut back on. IMO, I would not go past 1mm - 1.25mm Max of shim on this new quad. There is a ton of clearance for the screws VS the cage so this is a non issue. The pic with the cage on is with 1.5mm of shim. If you look at the nut you will see the washer is not center with 1.5mm of shim.


One of the things i noticed is the amount of dirt by the bearing in the cage. This new Kodiak only has 210 miles on so I am going to see if I can find some sort of filter to put in the intake side of this.
 

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Thanks for the work with the shim on the 450, others will know what to do now.
As for the amount, as there is still spline showing outside the cam plate, I would have no problem with 1.5 mm's of shim. As for centering the washer, I think you got close enough, and the washer is to keep the nut off (from contact with) the splines for full torque of the nut to the cam plate. I can see where a mm off the weight diameter will work too.
 

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What was your ratio with 1.5 of shims?
 

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Discussion Starter · #10 ·
What was your ratio with 1.5 of shims?

Good question. I did not put the belt on to check that. I will try to remember to check that.
 

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Discussion Starter · #11 ·
Thanks for the work with the shim on the 450, others will know what to do now.
As for the amount, as there is still spline showing outside the cam plate, I would have no problem with 1.5 mm's of shim. As for centering the washer, I think you got close enough, and the washer is to keep the nut off (from contact with) the splines for full torque of the nut to the cam plate. I can see where a mm off the weight diameter will work too.

I like your thinking.
 

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Following.

I think I remember looking up at one time and the 2018+ 450's came with 18 gr weights. Whereas the 2014 and older came with 14 gr. It'll be the last step in your process, just noting it while thinking about it.

I'd really like to ride an 2018+ 450 if I get a chance. See how much smoother they are with the improved motor mounts. Hard to imagine them running any cleaner with EFI than they already did though. My 450 is the best carbureted and smoothest running machine I've ever had.
 

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Discussion Starter · #13 ·
Following.

I think I remember looking up at one time and the 2018+ 450's came with 18 gr weights. Whereas the 2014 and older came with 14 gr. It'll be the last step in your process, just noting it while thinking about it.

I'd really like to ride an 2018+ 450 if I get a chance. See how much smoother they are with the improved motor mounts. Hard to imagine them running any cleaner with EFI than they already did though. My 450 is the best carbureted and smoothest running machine I've ever had.

Correct, the 18's & newer use 18g weights. As for riding the quad there is not much vibration with the rubber mounted engine. I wanted to get this done over the weekend but other things got in the way after I started on it. I may have to run out of town again tomorrow but I will get this done this week. I am planning on checking the stock secondary spring poundage as well.
 

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Discussion Starter · #14 ·
What was your ratio with 1.5 of shims?

With 1.5mm of shim the ratio was about 2.8 to 1. In the second photo you can see the yellow on the primary clutch about the 2:00 to 2:30 O-clock position
 

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Discussion Starter · #15 · (Edited)
So after I checked the ratio with 1.5mm of shim I decided on machining the sheave on a 2mm taper cut. This netted me almost dead on 3.0 to 1 ratio. Then I checked it with a 1/4mm shim which is about 3.05 to 1 and then with a 1/2mm shim which ended up about 3.1 to 1 ratio. I am not sure on how far I can go with this cover as its made a little different than the 700's are. So I started with the machined sheave and a 1/4mm shim. I will let the belt get use to that before going any further with shims and to see if I am hitting the cover at all.
 

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Discussion Starter · #16 ·
I did verify the Kodiak 450 is now using 18g weights. Now that the primary is back together is was time to start thinking about what I wanted to do with the secondary spring. I did notice some belt burn about 1/2" up from the bottom on the stock primary clutch so that is telling me the belt was slipping. I know a lot of guys with the older 450's are running 12-14g weights and a EPI blue secondary spring. Well I am not going to go to lighter weights at all and if the 12-14g weights work good with the blue secondary I need to be looking at a heavier spring than that. So first off I figured I better know what the stock secondary spring poundage is. The stock Kodiak 450 spring is... 3”= 130lbs, 2”= 200lbs, 1-3/4”= 217lbs. The reason why I have the 2" mark in there is my Grizzly secondary opens up to 2" not 1-3/4". I then compared my findings with the two stock grizzly secondary springs VS the EPI springs. I knew I had to go heavier than the EPI blue for the extra clutch weights but was not sure how much extra to go. I new I did not want to go to the extra finish poundage of the EPI Orange or Purple as that would drive my Rpm's up while cruising so I decided to go with my Stock Grizzly spring at 3”= 190lbs, 2”= 270lbs, 1-3/4”= 285lbs.


So after I had it all bolted back together I start it up and rev'ed it a few times to make sure every thing was working properly. All seems good so I bolted the clutch cover and ran it around the yard a few times and then up and down the road. On the way back I matted the throttle and I was amazed on how much this helped. It actually got up to 45Mph rather quickly. I did not hold it WOT as there is no reason to as my wife will probable never go 50Mph on it. As I was pulling into my yard I decided to do the ditch test. One side is a lot steeper than the other side is. So I pulled in so I would have to climb out of the steep side. The little 450 walked right up with a lot less throttle than it did before. So then I turned it around and rolled into the shallower side and gassed it coming out of the ditch. It caught me a little off guard when the front end came up about a foot all while spinning the rear tires. I did not even think the 450 would pull the front end at all ever. lol. I no for a fact it would not spin the tires before this and it defiantly would not lift the front end before going through the same spot on the ditch as I tried it before starting these clutch mods.


So at this point i am pleased with what I have done. After the belt breaks into the new sheave angle I will take a look and see just how much shim I can add before hitting the clutch cover. I looked at the bottom of the clutch/belt and I see I can go at least another 1mm lower on the primary sheave so as long as I am not wearing a hole in the cover I can add more shim and a cam plate mod. Now we need to try this set up out in the woods. I will update after we get another 100 miles or so on it.
 

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Discussion Starter · #17 ·
When I was looking up the torque specs I ran across this so I took a screen shot of the stock clutch ratio.
 

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Discussion Starter · #18 · (Edited)
Before putting all the plastic back on the 450 I decided to pull the clutch cover off and check to see if the belt is rubbing the cover and if so how bad, As well as seeing how much material was left before the belt rubbed a hole through the cover. The belt is hitting the cover barely right now at a 3.05 to 1 clutch ratio. Using a Micrometer and a .625" dowel pin as well as a .503" tool bit I was able to mathematically figure out just how much material was left. There is .092"or 3/32" of material left before rubbing a hole in the clutch cover. The belt sits above the secondary right now by 5/32 or .156" so to wear a hole in the cover the belt would have to be sticking out of the secondary by a 1/4". So at this point I will leave it and monitor the belt wear. FYI, The belt is rubbing on the bottom, below the secondary about the 7:00 O'clock position.


I will say getting to the clutch cover is kinda adventure. You can tell Yamaha has adopted the car manufacture idea on production and not the easy of working on them. To get the foot well off you are suppose to take the front and rear fenders off as the front and rear fenders slide into the foot well to get a water tight seal so you feet dont get wet. Thats nice for trail riding but it sucks for working on it. What i did was unbolted the foot well mounts while pulling the plastic foot well outwards. Then I was able to slide the foot well straight down and out of the way. It sucks but its a lot easier than taking every piece of plastic off the quad.


I also did a hole shot from a dead stop on the blacktop to see if the belt would slip or not. I know the belt is not broke into the new sheave angle but figured I would try to see if the secondary spring is stiff enough. I could feel the belt chatter for about 4ft and then it was gone. After I get the belt broke into the new sheave angle I will try that again to see if it slips or not and update then.
 

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Awesome everything worked out! Great info on the newer 450 too.
 

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Discussion Starter · #20 · (Edited)
Update, Yesterday my wife had the day off and wanted to go riding. We put 85 miles on and the clutching worked perfectly. She said it climbed a lot better, accelerated faster even in loose sand, and had a faster throttle response. I rode it for about 3 miles and I agree with her statement. The one thing I like is the back shifting is not real aggressive like it would have been with one of the EPI springs. If I lived in the mountains where you have long steep down hills I would probable opt for a EPI Orange spring for better back shifting to slow you down going down hill.

Another thing I noticed as well as my wife noticed is the fan dont run as often. This is telling me the clutching is more efficient and is not working the engine as hard while cruising. I checked the gas mileage and she was getting 28.7 MPG in the up hill direction of our ride and 32.6 MPG in the down hill direction for a average of 30.6 MPG. My wife is not a aggressive rider so if you are throttle happy expect to get less MPG than she does.

IMO, If you have a 2018 or Newer 450 and dont want to do a sheave mod yet I would add 1.5mm of shims and either a stock Grizzly secondary spring or a EPI Orange if you live in the mountains for better back shifting. I would also say I would at least put in a stock Grizzly secondary springs even if you are not shimming the clutch. That spring works wonders for the 450.

I will add to this thread if I do any changes but at this point we are both happy with what is done.
 
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