nodoo_s
New member
a friend and i just pulled out the drive shaft on my viper to change the track and the speedo bearing was bad but what i found was the chain case bearing was bad so i pulled it out and found that there was no seal on the outer edge of the bearing not the side that faces the chain case but the other side. i didnt find any pieces of plastic just looked like someone removed it. the shaft outer seal on the back side of the chain was fine. i would think that if the outer bearing seal came off i would have found pieces of the plastic or the outside seal would have been chewed up a little. anyways that bearing is bad too so i guess it was a good thing i was changing my track. is this common because the new bearing has a seal on both sides. just something some guys may want to look out for.
ModMMax
New member
Are you talking about the seal that installs into the chain case from the back side?
nodoo_s
New member
No, that seal was ok, on a normal bearing you have seals on both sides of the bearing. When i took my bearing out the side facing the outer seal had no plastic cover. it was exposed.
ModMMax
New member
There are lots of guys who know more about this than me, but my understanding is that because the chaincase runs in a lubricant, the bearings do not use a dust seal on either side like you would see on a bearing that relied on grease for lubrication. I'm pretty sure the stock ones I've removed had no dust seals. Aftermarket bearings come with dust seals. I've always removed them before installation in a chain case.
That is the norm on any latelmodel I have had apart. The bearing itself has the seal facing the chaincase side but the opposite side is open. There is however the seal in the Case that will seal over the jackshaft but it is a sepatate one on the case itself.nodoo_s said:
nodoo_s
New member
why would they remove the seal facing away from the chain case, it would have made sense for the one facing the chain case. so are you saying when i put in the new bearing to remove the seal on the chain case side or the other side or just leave it on?
I think your right, the only thing I can think of is that they want to allow the lube to seep through but keep larger contminents out.nodoo_s said:
As I said, the seal facing the chaincase at least according to Yamaha must be there for a reason.
As far as a recomendation, I honestly have never had that bearing go bad on me, driveshaft yes, jackshaft yes but never on the chaincase side. I would simply leave the seal intact myself, but I am sure others here will have more input.
nodoo_s said:
I agree with you it makes more sence to the seal the be on the other side, the new bearing i got only had a seal on one side to so i put it in the opposite way seems to work good.
98srx6
New member
Friction between the chain and gears causes "shavings" of metal to be released into the chaincase lube. The seal is on the inside of the bearing to keep these particles from getting into the bearing contact areas and decreasing bearing life.
Yamaha doesn't want the MUD in the chaincase getting into the bearing!!!!! good post!!!
bluehammer
New member
When we replaced ours we found the same thing you did. Seal on gear side, none on outer side. The seal in the housing is supposed to keep stuff out. But we replaced the bearing with a double sided seal. It made more sense to us to do that. No problems yet.
seal on 1 side for a reason
The seal on the chaincase side is to keep the large pieces of shavings from contaminating the bearing, oil is drawn thru the seal and center of bearing race and the reason there is no seal on the inside is so the chaincase seal that is on the driveshaft opening gets some kind of lube, if it didnt it would simply dry out and crack, not to mention burn on the driveshaft,letting water,dirt and such to contaminate the chaincase from the inside, also would place undo stress on the inside of the bearing, and if the water were to freeze, goodbye chancase/bearing mount.
The seal on the chaincase side is to keep the large pieces of shavings from contaminating the bearing, oil is drawn thru the seal and center of bearing race and the reason there is no seal on the inside is so the chaincase seal that is on the driveshaft opening gets some kind of lube, if it didnt it would simply dry out and crack, not to mention burn on the driveshaft,letting water,dirt and such to contaminate the chaincase from the inside, also would place undo stress on the inside of the bearing, and if the water were to freeze, goodbye chancase/bearing mount.
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bluehammer
New member
So, Don, what are your thoughts on running seals on both sides of that bearing?