upper gear bushing

[ClutchMaster]

We've all been waiting and writing about the 'real fix' for a long time. But that needs to come from Yamaha and /or Cat.

They say there’s a fix coming, I got $50 sayin it’s gonna be a different tensioner and possibly a harder/tighter upper bushing. With no sight glass now, you might also see a different amount of oil prescribed for fill level. Nothing we haven’t already discussed and recommend.

People still having issues are doing something different imo.


I helped a local guy who was having issues with bearing failure, he wanted me to come over give my 2 cents. When I set his tension at .125” bolt to tensioner the chain was so loose with the 21t top sprocket that it almost hit the center post when rotated backwards. He was unwilling to allow that kind of slack in the chain. He ended up doing 1 turn out from VERY finger tight and the bolt was still very close, around 035” clearance. He will have premature wear imo, but it will be better than before imo, he was only going 1/2 turn previously.

BOP is working on a fix, I like Travis’s ideas better than Yamaha anyway (they actually work!)

 

[STAIN]

I helped a local guy who was having issues with bearing failure, he wanted me to come over give my 2 cents. When I set his tension at .125” bolt to tensioner the chain was so loose with the 21t top sprocket that it almost hit the center post when rotated backwards. He was unwilling to allow that kind of slack in the chain. He ended up doing 1 turn out from VERY finger tight and the bolt was still very close, around 035” clearance. He will have premature wear imo, but it will be better than before imo, he was only going 1/2 turn previousl

Isn't it irritating when some asks for advice on a problem they cant fix and dismiss YOU for being wrong?

 

[Fast]

They say there’s a fix coming, I got $50 sayin it’s gonna be a different tensioner and possibly a harder/tighter upper bushing. With no sight glass now, you might also see a different amount of oil prescribed for fill level. Nothing we haven’t already discussed and recommend.

People still having issues are doing something different imo.


I helped a local guy who was having issues with bearing failure, he wanted me to come over give my 2 cents. When I set his tension at .125” bolt to tensioner the chain was so loose with the 21t top sprocket that it almost hit the center post when rotated backwards. He was unwilling to allow that kind of slack in the chain. He ended up doing 1 turn out from VERY finger tight and the bolt was still very close, around 035” clearance. He will have premature wear imo, but it will be better than before imo, he was only going 1/2 turn previously.

BOP is working on a fix, I like Travis’s ideas better than Yamaha anyway (they actually work!)

Who's they ,yamaha or articat

 

[ClutchMaster]

Jarett from Yamaha says it’s happening.

 

[Byam]

Ca

They say there’s a fix coming, I got $50 sayin it’s gonna be a different tensioner and possibly a harder/tighter upper bushing. With no sight glass now, you might also see a different amount of oil prescribed for fill level. Nothing we haven’t already discussed and recommend.

People still having issues are doing something different imo.


I helped a local guy who was having issues with bearing failure, he wanted me to come over give my 2 cents. When I set his tension at .125” bolt to tensioner the chain was so loose with the 21t top sprocket that it almost hit the center post when rotated backwards. He was unwilling to allow that kind of slack in the chain. He ended up doing 1 turn out from VERY finger tight and the bolt was still very close, around 035” clearance. He will have premature wear imo, but it will be better than before imo, he was only going 1/2 turn previously.

BOP is working on a fix, I like Travis’s ideas better than Yamaha anyway (they actually work!)

No sight glass

I have this one in my #22 NO OIL hole. 2867t67
Looks new after 1500km
I have did 10 oookm whit stock bushing. Always ~ 1/8 between tensioner and bolt. That’s it.

Inside the chaincase post rubbing? =yes
tensioner grooving through post and need bushing? = yes
Behind upper gear it should be a slug instead of snap ring?=yes

 

[74Nitro]

No sight glass

View attachment 155057



I have this one in my #22 NO OIL hole. 2867t67
Looks new after 1500km
I have did 10 oookm whit stock bushing. Always ~ 1/8 between tensioner and bolt. That’s it.

Inside the chaincase post rubbing? =yes
tensioner grooving through post and need bushing? = yes
Behind upper gear it should be a slug instead of snap ring?=yes


View attachment 155058

I just pressed a bushing into a 17 Cat with 12000 kms on original bushing about an hour ago. About half the teflon gone, but not as bad as some I've seen!

 

[Mototown]

Yamaha should just add 20 $ to the oil change kit & add a top gear to the packages . Then this thread would be long gone .... problem solved.

 

[ClutchMaster]

Ca
No sight glass

View attachment 155057



I have this one in my #22 NO OIL hole. 2867t67
Looks new after 1500km
I have did 10 oookm whit stock bushing. Always ~ 1/8 between tensioner and bolt. That’s it.

Inside the chaincase post rubbing? =yes
tensioner grooving through post and need bushing? = yes
Behind upper gear it should be a slug instead of snap ring?=yes
View attachment 155059



View attachment 155058

That’s the same bushing I’m running, glad to hear it’s working for you! A little harder than the 660 bearing, similar too a soft Ampco bushing.

In order of hardness,
Oilite on the left, 660 middle and aluma bronze on the right.

 

[ClutchMaster]

Great idea with the spacer/c-clip delete!

 

[74Nitro]

Hi Byam, what is the advantage of using a spacer in behind the gear instead of the snap ring?

 

[Byam]

Hi Byam, what is the advantage of using a spacer in behind the gear instead of the snap ring?

Just preventive, it make the system more reliable for low$$$... this picture is from one of my buddy who's mechanic for a yamaha dealer. He had seen couples snap ring failure, so this is his fix. we could probably use alu brz bushing whit bigger od !

 

[ClutchMaster]

Just preventive, it make the system more reliable for low$$$... this picture is from one of my buddy who's mechanic for a yamaha dealer. He had seen couples snap ring failure, so this is his fix. we could probably use alu brz bushing whit bigger od !

Hey now there’s a great idea! Make some collars 1.25” OD that press onto the driveshaft!
They would need heat treatment tho.

 

[ClutchMaster]

Pretty easy to bore out a gear for a larger bushing.

 

[cannondale27]

Pretty easy to bore out a gear for a larger bushing.

Thats what that guy on here did with that big Bronze looking Bushing thats alot of $. I would imagine by more surface area and the support of it against bearing both help the wear.

 

[twyztid]

I like the idea of having a channel for oil distribution machined into the bushing...it sure couldn't hurt.
I am starting to wonder if after a long lake or rail bed run we should be putting our sleds in reverse and backing up a bit to rotate the top gear and get some fresh oil in there...might help.
My bushing was obviously pretty dry and chattering on the jackshaft.

View attachment 154976

That is the Teflon that is worn off. Not necessarily from being "dry"