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Discussion Starter · #21 ·
Just a little update. We have over 500 miles on it now and I did a top end speed run to see if I lost any MPH with the clutching VS at the 200 mile mark before clutch mods. Stock was 50 to 51Mph. Its now at 54 to 55Mph so we gained a little Mph. Not that I really care as we normally run in the 13 to 34 Mph range but its nice to no it will go that fast if we wanted to.
 
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Discussion Starter · #22 ·
I forgot to add. Now that the belt is broke in to the new sheave angle there is no belt chatter like I had mentioned in post #18 at the hit of the throttle on concrete from a dead stop. The grizzly 700 secondary spring works great with the stock tires and normal trail riding. My wife and I both like the back shifting with the grizzly spring as it's not over powering like it would have been with the EPI springs. If you are a mudder, in the mountains, or have bigger tires you may like the quicker back shifting of the EPI springs.
 
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Thanks for documenting all of this. I was driving by and stopped in at a dealer today and was checking out a 450. They are a really neat machine and I'll bet they're a lot of fun in the twisty woods trails. It seems that Yamaha did a really nice job on the new FI 450 models... except eliminating diff lock.
 

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Discussion Starter · #24 ·
Thanks for documenting all of this. I was driving by and stopped in at a dealer today and was checking out a 450. They are a really neat machine and I'll bet they're a lot of fun in the twisty woods trails. It seems that Yamaha did a really nice job on the new FI 450 models... except eliminating diff lock.

You guys are welcome. The 450 is a blast to ride in tight trails but I dont get a chance to ride it much as the wife prefers her new 450 ride over my bigger grizzly.
 

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Hi I'm new to all these clutch mods, so this has been a really awesome read. Just to be clear, the 700 Grizzly secondary spring you used, was it from your 2017? Are they all the same? Also, is there anywhere I can get a machined sheave? I see that JBS has them, but they don't seem to have my year. I ride trails, and I love how you got extra bottom end and top end too with this setup. 2018 Kodiak 450 EPS.
 

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Discussion Starter · #26 ·
Hi I'm new to all these clutch mods, so this has been a really awesome read. Just to be clear, the 700 Grizzly secondary spring you used, was it from your 2017? Are they all the same? Also, is there anywhere I can get a machined sheave? I see that JBS has them, but they don't seem to have my year. I ride trails, and I love how you got extra bottom end and top end too with this setup. 2018 Kodiak 450 EPS.
Yes the Grizzly 700 spring is the same from 2007 - 2021. Yamaha PN# 90501-650A0-00. Contact Coop45 for your clutch machining and you are welcome to send him a link to this thread if you want. https://coop45.webs.com/

Just a FYI. Both Primary & Secondary clutch bolts are torqued to 74 Ftlbs.

Kinda funny you posted on this thread as I am doing normal maintenance and was/am going to update it today.
 

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Discussion Starter · #27 · (Edited)
UPDATE.
I'm doing normal maintenance and just wanted to update this thread. After the belt broke into the new sheave angle and 1400 miles later everything in the clutching is working awesome. The belt has wore around .009" and still has plenty of life in it. The new clutch ratio with the belt broke into the sheave angle including the 1/4mm shim that I put in when I did this is 3.2-3.25 to 1. If someone asked if I would do this mod again my answer would be Absolutely!!!
 

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Discussion Starter · #28 · (Edited)
I should also add I am switching this to a greaseless primary sheave. My wife normally rides behind me and all the sand dust just turns the grease in to a thick sludge mess. I have had my Grizzly 708 greaseless for over 2000 miles and its time for the 450 to go that way as well. I ordered Dr Pulley cam sliders & weights from Buggy Parts NW - Home Page


I don't know if the stock cam sliders & rollers in the 450 can go grealess or not so I just spent the money and bought the parts that are designed to go greaseless.

Stock weights are 18g and if you order the cam plate sliders make sure to order SP3015-X cam plate sliders.

 

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You should have asked the question here first before wasting a bunch of money on those weights. The oem can go greaseless with zero issues. Doesn't matter if it's a 700 or a 450. There are a couple 450s on here running stock greaseless already.


I love seeing the mods done to the 450 though, they are already an impressive bike for a 450 class, it's awesome to see them really walk all over the competition after mods.

Sent from my Pixel 5 using Tapatalk
 

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Discussion Starter · #30 · (Edited)
You should have asked the question here first before wasting a bunch of money on those weights. The oem can go greaseless with zero issues. Doesn't matter if it's a 700 or a 450. There are a couple 450s on here running stock greaseless already.


I love seeing the mods done to the 450 though, they are already an impressive bike for a 450 class, it's awesome to see them really walk all over the competition after mods.

Sent from my Pixel 5 using Tapatalk
If you look up the PN#. The Kodiak 450, 18 & newer uses the same weights as the old 660's from 2002-2008. I don't think you can run those weights greaseless. They also look different than the Grizzly weights.

2018 + Kodiak 450 weights... 5KM-17632-00-00
2016 + Grizzly weights...2UD-E7632-00-00

I am currently running my Grizzly weights greaseless in my Grizzly.
 

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If you look up the PN#. The Kodiak 450, 18 & newer uses the same weights as the old 660's from 2002-2008. I don't think you can run those weights greaseless. They also look different than the Grizzly weights.

2018 + Kodiak 450 weights... 5KM-17632-00-00
2016 + Grizzly weights...2UD-E7632-00-00

I am currently running my Grizzly weights greaseless in my Grizzly.
Yes you can still run them greaseless. The sole purpose of grease is noise suppression, not lubrication.


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@Zrt1200 ...thanks for the great 450 info. I have added it to my CVT collection
 
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Hey guys, so I've read this thread exhaustively, as well as several others, but I still have a question...I recently installed a Coop45 machined sheave in my 2018 Kodiak 450, and at his recommendation I also installed the purple Epi spring. I've only done a couple of short rides, and can definitely say that I gained some top speed (10km/h) and my bike pulls better down low as well. I didn't want to pound it too hard while breaking in my new belt, so I haven't gone too crazy yet. But I digress...my question is regarding the spring. I see that some people like to run a stock Grizzly 700 spring in their 450. What's the effect of this compared to the purple spring? Is it reduced engine braking compared to the Epi spring? Higher revving while cruising? Something else? Currently I'm still running my stock 25" tires with the stock steel rims, but I'm planning to go to 26" with alloy rims when the time comes to buy new rubber. Just to be clear, I'm not at all unhappy with my setup, but this question is burning my brain lol.
 

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Discussion Starter · #34 ·
The EPI purple will hold it in a lower ratio on take off a little longer and run a few more hundred RPM's while cruising. It will also have a little faster back shifting. Being I live where its mostly flat land I dont need the extra back shifting like the guy who lives in the mountains.
 

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Hey guys, so I've read this thread exhaustively, as well as several others, but I still have a question...I recently installed a Coop45 machined sheave in my 2018 Kodiak 450, and at his recommendation I also installed the purple Epi spring. I've only done a couple of short rides, and can definitely say that I gained some top speed (10km/h) and my bike pulls better down low as well. I didn't want to pound it too hard while breaking in my new belt, so I haven't gone too crazy yet. But I digress...my question is regarding the spring. I see that some people like to run a stock Grizzly 700 spring in their 450. What's the effect of this compared to the purple spring? Is it reduced engine braking compared to the Epi spring? Higher revving while cruising? Something else? Currently I'm still running my stock 25" tires with the stock steel rims, but I'm planning to go to 26" with alloy rims when the time comes to buy new rubber. Just to be clear, I'm not at all unhappy with my setup, but this question is burning my brain lol.
The secondary spring is the key to the Yamaha c.v.t. system, it keeps constant tension on the belt and is why Yamaha uses a wet clutch......while popo used fly-weights without a wet clutch. The secondary spring is engineered to apply just enough pressure for the amount of torque through the belt with the stock pulley ratio, and so when we magnify/multiply/increase the torque with primary mods the belt can slip, thus requiring a heavier spring.
Yes the heavier spring increases back-shift, but that's not the most important reason to change the spring.
 

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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.
Zrt1200,

I picked up a spare sheave for my Kodiak, and I see in your signature you machined a "3mm taper" on your Grizzly sheave.

Im a machinist by trade, with my own machine shop at home. I am going to chuck up the sheave in the lathe this weekend and make some cuts. When you say "3mm taper", are you just changing the angle to be 3mm deeper at the seal boss? Do you happen to know what the included angle is on an unmodified sheave?
 

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Discussion Starter · #37 ·
Zrt1200,

I picked up a spare sheave for my Kodiak, and I see in your signature you machined a "3mm taper" on your Grizzly sheave.

Im a machinist by trade, with my own machine shop at home. I am going to chuck up the sheave in the lathe this weekend and make some cuts. When you say "3mm taper", are you just changing the angle to be 3mm deeper at the seal boss? Do you happen to know what the included angle is on an unmodified sheave?
Are you talking about the 700's or the 450?? If you look at the qoute in the post you just replied it is a 2mm taper for the 450. For the 700 I cut the sheave twice. First with a 2mm taper and then with a 3mm taper. You can read about that & way more in this thread.....

 

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