Primary noise?

[HUS457]

Hey everyone. I had my 1st ride on the sled (other then laps around my house) yesterday. I noticed a squeal coming from what I thought was the belt. I had just put a brand new belt on. So I swapped it out for the old belt thinking that would fix it. It didn’t. The guys I was riding with who have a lot of experience with sleds and working on them say the noise is the primary and it’s characteristic of Yamaha. I know the primary creates noise, which I thought was more of a rattle. But this sounded like a loose serpentine belt on a car, but constant. If I was going between 10km/hr - 50km/hr it was making it. And maybe above 50 too but I just may not have heard it over the road noise. If I gave it a shot & let off it would stop for a moment, but then come back seconds later. Very annoying when we were on off trail runs. I know the obvious solution is go faster more often, or wear ear plugs but I still would like to correct this. Any ideas?

 

[HUS457]

To add, I did clean the primary recently. I used brake cleaner & compressed air. I left the primary in the sled when I did this.

 

[ateick]

These clutches definitely rattle but not squeal. How was the belt deflection once installed? How did it sit on the secondary. If not belt issue take the primary cover off and inspect the spring and check if arms moving freely.

 

[74Nitro]

Can't say I've ever heard a primary squeal while driving it. At a standstill, yes.

 

[74Nitro]

Brake squealing possibly? Does it change at all if applying brake pressure?

 

[HUS457]

Ateik- after 100 k on the new belt it’s about 1-2 mm above the top edge of the secondary. It’s definitely tighter then the old belt, but at idle with the track lifted it’s not so tight that it’ll spin the track. So I think it’s about right? I’ll take a closer look in the am & pull the cover off and look at the springs. Thanks for the advice!

74Nitro- I’m not sure, I didn’t try the brake to check, but ya when I stopped it would stop squealing either when I let off the gas or braked. I’ll have to take a closer look at that. It won’t do it in my garage though with the track off the ground. Only with a load on it.

 

[HUS457]

Does it matter which end of the primary spring is facing the sheave and which end faces the cover?

 

[74Nitro]

Does it matter which end of the primary spring is facing the sheave and which end faces the cover?

No

 

[mbarryracing]

Simple process of elimination... Take the belt completely off and rev the engine up a little to see if it still makes a squeal noise, because if it does then it's not the belt and you can look elsewhere.

I've heard belts make a weird squeal while moving, but would go away when the belt was changed. Both your old and new belt do the same thing, and still does it after cleaning the clutches.

Maybe it's not even the belt, it only squeals when moving under load, maybe it's a failing bearing in the jackshaft or driveshaft?

 

[HUS457]

I spent some time on it today. The alignment of the secondary was out just a small amount. 12.9mm & manual says it should be 13-16mm I believe. So I put a 1mm shim in. Also, the belt was sitting a bit low in the secondary. When I took the adjustment nuts off the back of the secondary there was already 1mm spacers there. So i put .5mm spacers in as well. But this brought the belt a little to high, like between 1.5mm & 2. And when I ran it with the skid lifted it was noisy. So I took the .5mm shims back out & left the 1mm ones in. Which dropped the belt a little low on the sheave as it was when I started. But it ran quieter so seems better. Everything was moving freely in the primary but it does seem like it needs a cleaning where the sheave moves on the shaft. There’s a little resistance there. I’ll tackle that in the days to come. Tx guys.

 

[HUS457]

Simple process of elimination... Take the belt completely off and rev the engine up a little to see if it still makes a squeal noise, because if it does then it's not the belt and you can look elsewhere.

I've heard belts make a weird squeal while moving, but would go away when the belt was changed. Both your old and new belt do the same thing, and still does it after cleaning the clutches.

Maybe it's not even the belt, it only squeals when moving under load, maybe it's a failing bearing in the jackshaft or driveshaft?

I thought that may be a possibility too. How would I check those to confirm? 7,200k on the sled.

 

[HUS457]

For the Canadian guys, any preference for a clutch pulling tool that we can order in Canada?

 

[maim]

i have bought them at the dealer and at royaldistributing and not noticed any real difference with the clutch pullers. if you pack with grease before using puller, it saves them getting bent/destroyed as often. i forget the grease when i get in a rush and bend them.

 

[HUS457]

Kk Tx maim!

 

[HUS457]

Spent a bit more on this today. Took the primary cover off and cleaned the slides, rollers & weights. Everything is moving freely. The rollers have a bit of rust on them, but they move freely. Took the secondary off & apart & cleaned it. Filed the flash down (I found the half of the sheave inside of the flash was actually higher then the outside half, seems there is more material on the inside half. I didn't want to file all that away thinking it might affect the balance. But I did file the edge of the flash down). Belt deflection & primary/secondary alignment is all in spec. But the noise is still there. Just under load. Still won't do it in the garage with the track off the floor. A run down my driveway with the Rouski wheels down didn't produce the noise either. But a run back up with a bit of a hill produced it once I got to 15k/hr. So I suspect a drive or jack shaft bearing is starting to fail. I'll repack both soon & see if that makes a difference.