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Discussion Starter #1 (Edited)
Is this knocking normal? Seems to stop after warming up, but have to look into more now. Just bought it used Saturday. Didn't hear it while looking at it and checked and listened over everything and seemed solid. Got it home after about an hour trip and started it in the bed of the truck and heard it. Pulled it around into the garage and didn't hear it anymore. Then I noticed, it only seems to do it on first startup when cold. Sounds like a piston or cam or something to me, but not sure. Reading through the forums it sounds as if the knocking is normal and clutch blamed a lot of the times.

https://bit.ly/2GSCnH0
 

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Is this knocking normal? Seems to stop after warming up, but have to look into more now. Just bought it used Saturday. Didn't hear it while looking at it and checked and listened over everything and seemed solid. Got it home after about an hour trip and started it in the bed of the truck and heard it. Pulled it around into the garage and didn't hear it anymore. Then I noticed, it only seems to do it on first startup when cold. Sounds like a piston or cam or something to me, but not sure. Reading through the forums it sounds as if the knocking is normal and clutch blamed a lot of the times.

https://www.dropbox.com/s/vugfryekn0..._1926.MOV?dl=0
Your video link isn't working. Post it to YouTube and link it here.
 

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Video link works now.

This is really just a guess and I'm no expert but the noise makes me think of a few things.
-Have you checked if the transmission is fully in neutral? Sounds a bit like gears trying to engage.
- Have you checked the primary sheave? Sounds like weights moving up and down the channels without any grease.
That's where I would start checking.
 

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Or maybe the belt is worn to the point that it's not wide enough to make contact with the primary sheaves when not spinning. And when you press on the throttle, they catch the belt which makes the secondary sheave jerk forward, making the transmission knock.

Again, just a guess.
 

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I definitely hear the noise you're talking about. To me, it doesn't sound too out of the ordinary as the CVT systems make plenty of noise - especially with the cover off. Can you post the details about which machine, miles, hours, service history (if you know any of it)? Might be a flat spotted roller weight or two causing some of this. It seems like I've noticed mine developing more noise like that after riding a few miles and the engine getting warmed up.

Edit: Maybe the previous owner set up the primary greaseless. The main purpose of the grease is said to be noise reduction anyway as other manufacturers don't use lube for their roller weights.
 
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@cashxx
I'm not hearing anything abnormal.
For comparison I just started my bike and I can duplicate the exact same knocking noise as yours. Mines always done it when cold.
I've serviced my cvt a few times and even inspected my wet clutch and never found anything wrong with anything.
 
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I'm not hearing anything abnormal.
For comparison I just started my bike and I can duplicate the exact same knocking noise as yours.
I have not watched the video but the CVT makes a sort of knock. Besides the fact that it is a 4wheeler. They all kinda have an engine knock.
 
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X2..normal
 
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Discussion Starter #10
Ok, thank you all! Been really worrying over it as I didn't noticed it when I went to look at it and never heard it. Then all of a sudden as soon as I get home to take it off the truck I hear it. It goes away I believe after it warms up a little and I think they had it running before I got there and probably why I didn't hear it.

Thanks for the input!
 

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Discussion Starter #11 (Edited)
So, got my new primary sheave and also put a new belt on. Watching videos on youtube, people put the belt on and slide the collar on and the primary sheave and you see the gears sticking out and they put the washer on then the nut. Looks so simple!

No matter what I do I can't get that primary sheave on to show the gears like in the video. Mine had a little sticking out before. I think it is because of the new belt. I pushed the sheave in and some grease came out and it looks like it is locked in the gears so I tighten everything down and the collar is against the back primary sheave so I think it is fine.

Any recommendations, since I have no space on the collar in against the back sheave, do you think I am fine then?
 

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So, got my new primary sheave and also put a new belt on. Watching videos on youtube, people put the belt on and slide the collar on and the primary sheave and you see the gears sticking out and they put the washer on then the nut. Looks so simple!

No matter what I do I can't get that primary sheave on to show the gears like in the video. Mine had a little sticking out before. I think it is because of the new belt. I pushed the sheave in and some grease came out and it looks like it is locked in the gears so I tighten everything down and the collar is against the back primary sheave so I think it is fine.

Any recommendations, since I have no space on the collar in against the back sheave, do you think I am fine then?

Sounds like you may have pinched the belt and the came plate may not be seated on its splines properly. Was your secondary sheave opened up enough using the two pusher bolts to give you the proper slack for the belt before sliding on the primary sheave on the collar? You really need to see the splines showing threw the cam plate before sliding on the washer and tightening the nut. The belt needs to be slacked off to give you the clearance. I often install the primary with no belt in place for exactly this reason.
 
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Did some of your roller weights come out of there Chanel’s holding cam plate out during installation? and belt pinch like @Vincent had mentioned. You need to see the shaft splines.
 

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You MUST have splines showing when you install the sheave. If you don't have enough splines showing for the cam plate to fully engage on them, you will totally grenade your CVT in seconds to minutes when you run the machine. The guys above have provided great advice on the things to look for. Installing the primary while holding the cam plate seated firmly so the weights don't fall out is critical. I know some guys stuff a piece of foam or something between the grease cover and the cam plate while doing the install to assist and then remove after torquing the primary nut. Keep at it, you'll figure it out.
 
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....... You really need to see the splines showing threw the cam plate before sliding on the washer and tightening the nut. ....
....You need to see the shaft splines.
You MUST have splines showing when you install the sheave. If you don't have enough splines showing for the cam plate to fully engage on them, you will totally grenade your CVT in seconds to minutes when you run the machine. ....
Agree 100%..

You need to see 2mm of spline sticking out of the camplate.
Make sure the belt is out of the way. Stuff a piece of gas line hose or paper or rag in the primer to hold the camplate and rollers in there proper positions.After removing the jack bolts from the secondary rotate the CVT until the belt comes to the outer edge of the secondary. If all looks good only then start the engine.
 

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Agree 100%..

You need to see 2mm of spline sticking out of the camplate.
Make sure the belt is out of the way. Stuff a piece of gas line hose or paper or rag in the primer to hold the camplate and rollers in there proper positions.After removing the jack bolts from the secondary rotate the CVT until the belt comes to the outer edge of the secondary. If all looks good only then start the engine.
... after you re-install the support cage. :smile2:
 

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Discussion Starter #17
Sounds like you may have pinched the belt and the came plate may not be seated on its splines properly. Was your secondary sheave opened up enough using the two pusher bolts to give you the proper slack for the belt before sliding on the primary sheave on the collar? You really need to see the splines showing threw the cam plate before sliding on the washer and tightening the nut. The belt needs to be slacked off to give you the clearance. I often install the primary with no belt in place for exactly this reason.
I took it back apart and got it. I used the longer bolts to spread the secondary more and it gave me more slack for the belt then. Was able to put the primary back on and things looked normal then.

Thanks again everyone!
 
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