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Greetings...after numerous google searches and a fair amount of lurking, I joined up hoping for help. Mods- if I chose the incorrect forum, please move the thread, or advise on what I should do...

So, Long story long:
2009 Grizzly 450, all stock (500 miles, 170 hours).

Due to my work volume, it sat for a bit. Last time I ran it, it was fine.

Fired it up and noticed top speed was 20 MPH. I went to the google machine and started searching...based on the info I found, I started from basic maintenance then proceeded to cheapest options based on my research. I changed the oil (10w40 Wet Clutch approved), Changed the air filter, spark plug, cleaned the spark arrestor and then changed the CVT Belt. No improvement.

So, I removed the primary sheave and inspected/re-greased. No Change.

Next, I observed the CVT in action. In neutral, the primary and secondary work as expected (Primary side rises/Secondary falls). However In High/Low (under load) the belt never moves from the starting position. By process of elimination, I am forced to conclude that it is the wet clutch. Given the cost of a full replacement for this part, I am wanting to confirm with you guys that my conclusion is correct. I really do not want to throw any more parts at it.

Any advice is greatly appreciated and if there is additional information needed, please let me know!

Thanks in advance and sorry for the long post/wall of text. 馃嵒

LT
 

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Pull the wet clutch and show us a few pictures before ordering parts.
 

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You may have some of the primary weights out of position, this is a very common mistake when removing the primary and easy to do. Take the primary sheave off and then take it apart and make sure they are sitting in there channel properly. If one or two are out it will make your bike feel very under powered. Since you already took it apart you know what I鈥檓 describing. If you don鈥檛 keep it pinched together when putting it back on a roller weight can pop out. Check these again before you buy any more parts.
 

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Discussion Starter #5
You may have some of the primary weights out of position, this is a very common mistake when removing the primary and easy to do. Take the primary sheave off and then take it apart and make sure they are sitting in there channel properly. If one or two are out it will make your bike feel very under powered. Since you already took it apart you know what I鈥檓 describing. If you don鈥檛 keep it pinched together when putting it back on a roller weight can pop out. Check these again before you buy any more parts.
Will do. I assumed that because it was functioning properly in neutral when throttled that it was ok, but I will definitely check it again to be sure.
 

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Let us know your pulley ratio when you remove the cover.
 

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Welcome. Many active members here to to help you get this sorted out.

All suggestions of what to look at is definitely where you should be checking. Couple of questions for you that may help everyone help you:

Did the top speed of 20mph change in any way from before you dug into this issue, started making changes and now it only tops out at 20 mph? A bit of clarity here might help.

In Neutral, does the engine sputter or do anything that does not sound "normal"?

I would remove your Primary and check the weights that they are in the correct channels like mentioned. When reassembling, a nice helpful trick is to jam a piece of cut and folded over garden hose between the Primary cover and cam plate to hold it in place while bolting it back on.

Did you service (clean and grease) the Secondary while you were in there. Nothing sounds out of order with the Secondary, just curious if you serviced it too. Also, good chance your OEM CVT belt was fine. Many state that the OEM belt is the best one out there and advise sticking with OEM. Oh, and pulley ratio can be determined by marking both the primary and secondary and then rotating by hand... with the engine turned off. Go for one full revolution of the secondary, count how many times the primary rotates.
 

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@LitigiousTiger ...Before you pull you CVT apart again. Inspect the throttle verify that it is actually opening the carburetor fully. Check the throttle speed limiting screw.

97990
 
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Discussion Starter #10
Welcome. Many active members here to to help you get this sorted out.

All suggestions of what to look at is definitely where you should be checking. Couple of questions for you that may help everyone help you:

Did the top speed of 20mph change in any way from before you dug into this issue, started making changes and now it only tops out at 20 mph? A bit of clarity here might help.

In Neutral, does the engine sputter or do anything that does not sound "normal"?

I would remove your Primary and check the weights that they are in the correct channels like mentioned. When reassembling, a nice helpful trick is to jam a piece of cut and folded over garden hose between the Primary cover and cam plate to hold it in place while bolting it back on.

Did you service (clean and grease) the Secondary while you were in there. Nothing sounds out of order with the Secondary, just curious if you serviced it too. Also, good chance your OEM CVT belt was fine. Many state that the OEM belt is the best one out there and advise sticking with OEM. Oh, and pulley ratio can be determined by marking both the primary and secondary and then rotating by hand... with the engine turned off. Go for one full revolution of the secondary, count how many times the primary rotates.
I noticed no change in top speed after all steps I have taken (it is the same as it was before the work began)

In neutral, the belt has full travel on both sheaves. The only time it does not move is when it is in gear and the throttle is activated. I did not observe any hesitation in the throttle and it revs well. I did not hear anything that sounded abnormal (to my untrained ears, anyway)

I did not service the secondary. When I removed the primary, the grease and components actually looked ok, but I cleaned and re-greased since it was already disassembled. Given my observations on the primary, and adding the fact that I could not find a large enough socket to remove the spring retainer nut from the secondary, I took a chance and let it be.

The pulley ratio appears to be 2 5/8 rotations on the primary to 1 rotation on the secondary.
 

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Discussion Starter #11
@LitigiousTiger ...Before you pull you CVT apart again. Inspect the throttle verify that it is actually opening the carburetor fully. Check the throttle speed limiting screw.

View attachment 97990
I apologize for omitting this from my original post. This was one of the first things I checked. The Throttle cable has full movement at the handle bar end and at the carb end. The limiting screw is set to the specs in the manual for full speed operation.
 

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Will do. I assumed that because it was functioning properly in neutral when throttled that it was ok, but I will definitely check it again to be sure.
I was thinking by your reports the wet clutch is slipping preventing top speed, that the engine is gaining high r.p.m. with low ground speed.
I asked for the ratio as this lets others know if a weight is out without taking anything apart. And if you take the primary apart and nothings wrong, I think you need to go to the wet clutch for pictures and wear inspection.
You running taller tires?
 

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Your ratio is in the stock range, if the weights were out the number wold be much different.
 
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Discussion Starter #14
I was thinking by your reports the wet clutch is slipping preventing top speed, that the engine is gaining high r.p.m. with low ground speed.
I asked for the ratio as this lets others know if a weight is out without taking anything apart. And if you take the primary apart and nothings wrong, I think you need to go to the wet clutch for pictures and wear inspection.
You running taller tires?
Understood. I already have 2/3 of the work done to remove the primary again and check the weights. Tires are stock, no lift kit, really, no mods at all except a small LED light bar I added, which I am not even sure would qualify as a "mod"
 

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Because of your ratio I can tell you have no weight out of the channel, this will be confirmed when you remove the primary to get at the wet clutch.
I asked about the tires because tall tires cause added drag to the system, and without c.v.t. mods the wet clutch takes the hit going slow.
 

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Discussion Starter #16
Because of your ratio I can tell you have no weight out of the channel, this will be confirmed when you remove the primary to get at the wet clutch.
I asked about the tires because tall tires cause added drag to the system, and without c.v.t. mods the wet clutch takes the hit going slow.
Got it. I re-checked the weights this morning-all looks good. I guess it is time to recognize that I am going to have to spend some coin and replace the wet clutch. Hard to believe given the fact it has less than 1k miles. On a positive note, I have learned more about my ATV in the last two weeks than I had in the 5 years I have owned it. Does this site have sponsors or recommendations for parts purchases?

Do you recommend I go ahead and replace the entire thing (drum, wet clutch carrier, gasket, oil seal, one way and pilot bearings) or is that to be determined after inspection?

Thanks again for you help and all others responding in this thread.

LT
 

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Inspect first to confirm the problem is with the wet clutch mechanism.
As for this wear in 1000 miles, if you go slow, tow or work the system hard going slow in high gear the wet clutch is what suffers most. C.V.T. mods help reduce wet clutch loading.
After inspection, if the wet clutch is failing, I would order the required parts from;
Then while waiting for those parts;
I would have COOP machine the primary sheave. He can also supply shims to you first.
Then if the belt slips add a stronger spring from E.P.I. Performance...or COOP can supply one for you.
First things first, find your current problem :)
 
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Discussion Starter #18
Inspect first to confirm the problem is with the wet clutch mechanism.
As for this wear in 1000 miles, if you go slow, tow or work the system hard going slow in high gear the wet clutch is what suffers most. C.V.T. mods help reduce wet clutch loading.
After inspection, if the wet clutch is failing, I would order the required parts from;
Then while waiting for those parts;
I would have COOP machine the primary sheave. He can also supply shims to you first.
Then if the belt slips add a stronger spring from E.P.I. Performance...or COOP can supply one for you.
First things first, find your current problem :)
Allright, got the wet clutch out. There is wear on the housing wall. Also, the "pads look degraded in parts and are actually even with the metal on the sides. Pictures below for analysis by the guys that have been helping.
97995
97996
97997
97998
97999
98000
drum inside1.jpg drum inside2.jpg wet clutch1.jpg wetclutch2.jpg wetclutch3.jpg wetclutch4.jpg
 

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The WC looks fine. The marks on the clutch housing are normal.
Only thing I see that is wrong is that one way is in the housing backwards.
 

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The shoes look fine, the even with the metal is because the shoe(s) are retracted.
Tell us more about the one-way, you counted the ratio so I assumed the primary turned correctly by hand...counter clockwise to count, and locked to the crank going clockwise.
Did you turn the primary clockwise to count?
 
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