Chaincase gear wear

FernieHawk

Active VIP Member
Joined
Dec 1, 2008
Messages
1,965
Reaction score
5,563
Location
Fernie, BC
M8000 Chain case wear.jpg

This is the wear on my 3500 km 2017 M8000 lower chain case gear. Any opinions on if this is normal and what the replacement schedule should be? My understanding is this is an aluminum gear.

I bought the sled just over a year ago and this is my first look at it. I haven't had a sled with a chain-case since 2008 and I've gone through 4 earlier M series chassis that had the Diamond drive gear cases...I always used the BDX gear and bearing upgrades.
 

Jorg Jorgenson

Active VIP Member
Joined
Oct 1, 2016
Messages
757
Reaction score
2,341
Location
Not close enough to the Mountains, AB
View attachment 231418

This is the wear on my 3500 km 2017 M8000 lower chain case gear. Any opinions on if this is normal and what the replacement schedule should be? My understanding is this is an aluminum gear.

I bought the sled just over a year ago and this is my first look at it. I haven't had a sled with a chain-case since 2008 and I've gone through 4 earlier M series chassis that had the Diamond drive gear cases...I always used the BDX gear and bearing upgrades.

This is what my gear looks like after only 800ish miles, and you are correct it’s an aluminum gear from factory. Many upgrade to steel so it doesn’t wear down. 3500km seems like a lot, of you’re opened up might not be a bad time to replace components as preventative maintenance

a03892b529fd587b67d659d0382cffd0.jpg


my tensioner was in a different position to accommodate for the worn down gear. I guess if you still got room to take up the slack, you could keep running it? Not recommended perhaps?
 

papajake

Active VIP Member
Joined
Dec 5, 2006
Messages
2,941
Reaction score
5,885
Location
Didsbury, Alberta
Do you have to take the cover off to adjust the chain tension seems like a lot of wasted oil if that’s the case
 

rsmorin1

Active VIP Member
Joined
Jul 24, 2012
Messages
212
Reaction score
502
Location
Cochrane, Ab
Do you have to take the cover off to adjust the chain tension seems like a lot of wasted oil if that’s the case

It's an auto tensioner.

I'm going to replace my gears and chain soon with the HYVO set - I'm about 2200KMs on mine. I changed the oil at about 1000 kms. I did a nice clean, wiped out as much aluminum & brake clean to get it as clean as possible. Put new oil in, ran it on the sled stand for a minute and looked like an aluminum milkshake in the sight glass. I will replace after this season - just need to confirm gearing.

https://venomproducts.com/index.php/parts-catalog/2-stroke-procross--proclimb-kits
 

Clode

Active VIP Member
Joined
Jan 8, 2012
Messages
29,550
Reaction score
46,587
Location
BC
replace everything, that's a crazy amount of aluminum contamination, bottom gear is toast
 

1200

Active VIP Member
Joined
Nov 11, 2010
Messages
543
Reaction score
615
Location
k town
Just junk who the smart guy thought it was a good idea to put alum gear in chain case
 

Lund

Active VIP Member
Joined
May 4, 2013
Messages
4,246
Reaction score
11,290
Location
Vernon/Kelowna
We have been installing Yamaha gears and chains in all our Cats. The OP has nothing usable, gears, chain and bearing and seals, all pooched. Upper gear might be usable if your on stock power.
 

FernieHawk

Active VIP Member
Joined
Dec 1, 2008
Messages
1,965
Reaction score
5,563
Location
Fernie, BC
Well this certainly did not look good to me when I opened it up, but I wasn't sure what was the norm for an aluminum geared chain-case. Is aluminum considered a lubricant...LOL.
 

Lund

Active VIP Member
Joined
May 4, 2013
Messages
4,246
Reaction score
11,290
Location
Vernon/Kelowna
Here is the Yamaha part # for the lower gear, with that you will be able to match the chain and top gear if you wish. Or if your dealer isn't smart enough let me know and i'll post the other #'s

50T Lower gear #8JP-G7587-00-00.
 

378Cat

New member
Joined
May 16, 2020
Messages
1
Reaction score
2
Location
Manitoba
[FONT=&quot]3602-024 is the Cat part number for the 50 tooth light weight steel gear used in the newer High Country and some of the international Alphas. Put one in my 21 Alpha before it hit the snow. Can’t stand seeing the aluminum in the oil with in the first ride. [/FONT]
 
Top Bottom