apex lower chain case bearing

[Lonerider]

I am building a crashed sled & about to install the chain case, I am looking at the lower bearing from the OUTSIDE of the chain case by the drain plug I have a black seal on the case, but no seal on the bearing as I look in from this side, but there is a seal on the bearing from inside of the chain case. I did not change the bearing-the way I got it,

My question is this bearing installed backward? I thought the chain case should lube this bearing, therefor there wouldn't be a seal on the bearing inside of the chain case?

?? looks backward, its not greased,

 

[TBay Sledhead]

Seal goes to the inside of the chain case. Grease the bearing with some marine grease.

 

[Lonerider]

OK thanks,

 

[Irv]

Seal goes to the inside of the chain case. Grease the bearing with some marine grease.

Always thought the same thing, that the chain lube lubed the bearing?

If it is sealed, then how is it lubed?

 

[suprfst]

Grease is how its lubed and yes some chaincase fluid will get in there eventually. The biggest benifit of the seal being in place is to keep the metal shavings from chain and gears OUT of the bearing.

 

[Irv]

Grease is how its lubed and yes some chaincase fluid will get in there eventually. The biggest benifit of the seal being in place is to keep the metal shavings from chain and gears OUT of the bearing.

Never thought of that but that makes perfect sense

Too bad Yamaha never came out with a magnetic dipstick like other manu's have had for years and years now

 

[actionjack]

Maybe I am wrong but isn't the Dipstick magnetic?

 

[Blue Dave]

Seal goes to the inside of the chain case. Grease the bearing with some marine grease.

Mmmm..... now you have me second guessing myself on my bearing replacement project. I thought that I paid very close attention to the orientation of the original lower chaincase bearing side seal and that it was facing out.

I still have the original lower chaincase bearing and it clearly has only one side seal. The two original upper chaincase bearings have no side seals so there is no chance of installing them backwards.

Are you 100% certain that the seal should be facing in? I have not installed the chaincase yet or even pressed in the lower oil seal yet so I can easily press the bearing out and press it back in with the side shield facing in if this is truly the correct orientation. Please confirm.

 

[Blue Dave]

Seal goes to the inside of the chain case. Grease the bearing with some marine grease.

Mmmm..... now you have me second guessing myself on my bearing replacement project. I thought that I had paid very close attention to the orientation of the original lower chaincase bearing side seal and that it was facing out.

I still have the original lower chaincase bearing and it clearly has only one side seal. The two original upper chaincase bearings have no side seals so there is no chance of installing them backwards.

Are you 100% certain that the seal should be facing in? I have not installed the chaincase yet or even pressed in the lower oil seal yet so I can easily press the new bearing out and press it back in with the side shield facing in if this is truly the correct orientation. Please confirm.

 

[TBay Sledhead]

I went and looked in my chain case with the original bearing and seal is in.

 

[Blue Dave]

Thanks for the fast reply T-Bay

You know what they say about getting old, the first thing to go is your memory and the second thing is......Mmmmm........???????.......Mmmmm........

I guess that I had better start taking more pictures as I am disassembling things!

 

[Blue Dave]

My local Yamaha dealer told me that when they replace this bearing they always install the new bearing with the open side towards the inside of the chaincase and the sealed side towards the tunnel like in my pictures.

Mmmm.....what to do, what to do? I like that the bearing is better bathed in oil with the open side facing towards the inside of the chaincase. My dealer feels the same way and said that he wouldn't worry about metal contamination as it should be negligible.

I change my chaincase gear lube yearly and I am thinking that the contaminated gear lube that will eventually find its way past the bearing seal will be trapped inside the bearing during a gear lube change if the seal is facing towards the inside of the chaincase.

Anybody else care to share their thoughts one way or the other?

 

[stevewithOCD]

Yamaha sends it sealed side in the chaincase. The theory is it will hold out metal particles, but still allow oil to go through. Most people turn it around. It works both ways. I magnetize the plug so i'd rather see that bearing constantly oiled. My 2 cents...

 

[Blue Dave]

Thanks Steve,

I have OCD as well so it is killing me to deviate from how Yamaha installed this bearing at the factory.

I think that Yamaha probably installs this bearing with the seal facing towards the inside of the chaincase realizing that many owners will neglect to change the gear lube yearly and this offers some protection against metal particles that will contaminate the gear lube especially during break in.

With 6000 miles on my sled and the gears and chain "worn in" I believe that with yearly gear lube changes that this bearing is better off installed with the open side facing the inside of the chaincase.

 

[ZapeX2]

I just changed mine and it was, and now it is still oriented with it being open to the chainside for lubrication.