KTM Rear Axle Bearing Replacement

[_RG_]

So, after putting the 530 on its hitch hauler for the trip home – decided to check the snuggy factor by giving a little horizontal tug on the back tire.

CLUNK…wait that ain’t good. Who made that noise? Again – CLUNK. Aw crud! I’m guessing rear axles aren’t supposed to make that sort of sound. Hmmm…looks like the rear bearings might be a little shaky there.

*Fast forward - parts on hand - back in the shop*
Tire off. Rim resting on the mighty magic work bucket. Proper tunes dialed in. Comfy rolling chair...assorted tools on-line...knuckles prepped for their normal fair share of abuse.

First little axle spacer thingy pulled out of the hub. (Warning - Very technical terms used throughout this narrative)

Antique drift punch misused as a seal puller – again. Seal popped right out.

Hmmm… looks like seal hasn't been very effective lately.

Pretty sure healthy bearings don't look this way. Chain side sees a lot of nasty forces.

Other (brake) side looks better and has a pretty good sized snap ring to provide fun and entertainment.

Snap ring out of the way - finally located and retrieved from under the fridge... and a much happier looking bearing in view.

Antique punch misused to drive out the opposite side bearing. THERE IS AN ALUMINUM FLANGE ON THE INSIDE OF BOTH SIDES OF THE HUB. These hold the bearings and should not be abused by the punch. Make very sure we’re hammering on the bearing’s edge and NOT THE ALUMINUM FLANGE.

Fixing to wail away.

Inner part of the bearing came out. Left the outer ring in place. Aright! Got the little dude coming out.

You can see the flange here that supports the bearing. Could stand a little cleaning in there. Brake cleaner does a fine job.

Steel brush rotated around helps knock loose some of the tougher gunkage.

Old stuff that dropped out of the hub and into the mighty magic work bucket.

The carnage of obscene torque and abuse over time.

Much better.

Everything cleaned up ready to go back together.

Shiny new parts!

It’s way better if we remember to put the spacer in BEFORE seating the second bearing. (Don’t ask…)

Bearing started – gently – little taps all around the OUTSIDE.

Yehaaaw!

Other side… we never – no, not ever - strike the inside hub of the bearing. Only around the outside ring.

Seal/bearing driver in action - after the bearing is square in the hub and started on its way.

Seal going in with the help of a little grease around its outer edge.

Drive side looking good.

Brake side good to go. ***This bearing kit comes with thicker bearings which requires the big snap ring being left out. It really doesn't seem necessary considering how things fit together.***

Just a little dab’ll do ya! Inside lips of seal lubed.

New axle spacer thingys going on.

No left over pieces (cept for the big snap ring).

Alrighty! Job done and ready to get back in the game.

 

[Cagiva 549]

Wheel bearings are lubed every time tires are changed on my bikes well over 50 K on several bikes with no bearing failures . SEYA

 

[Gravel Guy]

Wheel bearings are lubed every time tires are changed on my bikes well over 50 K on several bikes with no bearing failures . SEYA

I do the same on my bikes.....great write up, RG!

 

[Liteitup]

It’s way better if we remember to put the spacer in BEFORE seating the second bearing. (Don’t ask…)

Having just replaced the bearings on the rear wheel,I read this and snickered. Then I went to the garage and promptly left the spacer out on the front wheel.

 

[CleatusJ]

It’s way better if we remember to put the spacer in BEFORE seating the second bearing. (Don’t ask…)

Having just replaced the bearings on the rear wheel,I read this and snickered. Then I went to the garage and promptly left the spacer out on the front wheel.

So that's what caused all those scars on foreheads.

 

[Vinny]

Very nice. I'll start doing a check on them with each tire too.

 

[greeneggs&ham]

Great Job RG! The only thing that I would add is... And this is TOTALLY up to all of you out there,,, is I pull the seal from one side and stuff the bearing with grease... your choice totally. I've heard good friends argue over this. People, it is just my way.

You did everything right RG. Well maybe, I was not there to hear the exuberant vocal exchange with the spacer. But I bet you taught it a word or two.

Also I never let you know how much I enjoyed your writings on the Mad Tire Science Academy. You make Slime seem noble.

Sam

 

[Cagiva 549]

I had a sales slut get all in my face about that once , He told me the bearing manufactures were perfect and put the exact right amount of grease in there when they made the bearing . After 40 + years of fixing engineering screw ups I did give it back to him with both barrels . Maybe thats why I get 4 to 5 times the normal design life out of stuff . I am not into the american way , Buy a new one every year . I like to do it right the first time and enjoy it . SEYA

 

[E.Marquez]

I had a sales slut get all in my face about that once , He told me the bearing manufactures were perfect and put the exact right amount of grease in there when they made the bearing . After 40 + years of fixing engineering screw ups I did give it back to him with both barrels . Maybe thats why I get 4 to 5 times the normal design life out of stuff . I am not into the american way , Buy a new one every year . I like to do it right the first time and enjoy it . SEYA

Three points:

1: many times it is the accountant, editor or correct lawyer which causes what the end user calls ,a "design fault" or an engineering error

2: sales people rarely know more then what the computer or manufacture says about the product... They exist to sell you something from their line, not to tell you how to maintain it.

3: I am very much into the American way my grandfather, mother, my mentors growing up taught me..... Buying new every year is NOT what I learned, but the opposite, maintain, fix, repair.. New is bought because of need or want but never for lack of work to fix what you have.

Sorry one more, good job on the bearings and yes even the greasing of them. For those that do this... Please remember many grease types when intermixed lose protective and lubrication property's.
Not all types of thickeners are compatible with each other. When replenishing old grease, you should try to use a type with either the same kind of thickener or one that is compatible. If you don't know what kind of grease you're replacing, try to clean out the old grease, if possible. If you can't get the old grease out of a fitting, then put in enough new grease to push out as much of the old stuff as you can. You will find the information you need about the kind of base used in your grease somewhere on the label or packaging. The manufacturer may refer to the base as "base", "thickener" or "soap".

As you are not likely to know if what is in the bearing either ask the manufacture (or the sales person) what the NLGI National Lubricating Grease Institute, grade or consistence number is... And match that.. Or follow the general guidelines above.

 

[SilverBullet]

Nice write up RG.

Whenever possible I freeze the bearings overnight before installing. Doing that they drop in much easier and very little force is required to seat them.

My question for the more knowlegdable mechanics here is this not a recommended method? I seldom read or hear of anyone else doing this.

_

 

[jqueen]

Nice write up RG.

Whenever possible I freeze the bearings overnight before installing. Doing that they drop in much easier and very little force is required to seat them.

My question for the more knowlegdable mechanics here is this not a recommended method? I seldom read or hear of anyone else doing this.

_

I'm not one of the more knowledgeable mechanics, but I've seen several reports of people freezing bearings before install, or heating the piece they install into,, or both.

 

[TwoSmokeDS]

I'm not one of the more knowledgeable mechanics, but I've seen several reports of people freezing bearings before install, or heating the piece they install into,, or both.

Just use a bigger hammer. That always works.

 

[E.Marquez]

Nice write up RG.

Whenever possible I freeze the bearings overnight before installing. Doing that they drop in much easier and very little force is required to seat them.

My question for the more knowlegdable mechanics here is this not a recommended method? I seldom read or hear of anyone else doing this.

_

Yes it works.. as well as heating the hub (or other assembly) up with a heat gun...and freezing the bearing.

Ive stopped freezing critical bearings (crank) and those I can not see, flush with lube after install.

Found that condensation will form very quickly on the bearing, and bearing material and posture do not go together. A Crank bearing can start to have rust form in minutes if unprotected from lube and moisture is present.

Heating the cases or hubs alone will allow the room temp bearing to go in with ease.

If you do freeze the bearing... make sure to protect it first with a solid film lube.. install, then flush well with lube to drive out an condensation .

 

[_RG_]

Thanks for the great ideas! I've used the heat/freeze approach to bushings/shafts and such when doing a press fit but not on hubs etc. And why not grease the doggone bearings? We've all packed wheel bearings on trucks and trailers since they invented the wheel...just never occurred to me to do it on a motorcycle. I'll surely look into at the next tire change.

 

[TwoSmokeDS]

We've all packed wheel bearings on trucks and trailers since they invented the wheel...just never occurred to me to do it on a motorcycle. I'll surely look into at the next tire change.

You shouldn't have to. These cartridge bearings designed to be forever lubed.

If you lube it, you run the risk of damaging the seal. And who knows if your grease is compatible with the stuff already inside.

 

[ghostrider1964]

Startin' to sound like an oil thread

 

[greeneggs&ham]

What was it I said??? "your choice totally" This is why I put up the disclaimer. I don't think everyone is going to agree, it's just my way.

I wrote several lines after that last sentence about people's opinion's and such. But it has no business here, it's not about RG's fine bearing replacement and how he was trying to help all of us out. Thank you RG.

And Thank You Eric, always enjoy reading your writings. Great point about the moisture.

Sam

 

[_RG_]

Startin' to sound like an oil thread

Nah...more of a lively discussion between friends gathered round a campfire after a long day's ride on the trails. Sharing from their understanding and (in some cases) considerable experience.

Ghost, how do you deal with wheel bearings? I've never gone deeper than the rims on my GS. What kind of bearings do these Bavarian beasts use anyhow?

 

[ghostrider1964]

Nah...more of a lively discussion between friends gathered round a campfire after a long day's ride on the trails. Sharing from their understanding and (in some cases) considerable experience.

Ghost, how do you deal with wheel bearings? I've never gone deeper than the rims on my GS. What kind of bearings do these Bavarian beasts use anyhow?

Only bearing I have replaced was a crown bearing on rear final drive of a 1150 GSA. The BMWs are bathed in oil and that helps alot on the rear unless your seal fails and you lose your oil. Bout a 10 minute job to change seal if that. Rear Final drives holds 180 ML of Gear oil which I change every other oil change. It has always been clean and metal free. On the front, I am like Cagiva....molygrease and lots of it. I clean it out about every other front tire. I have had plenty of "sealed" "lifetime" bearings fail so I started using grease with a positive result.

 

[ghostrider1964]

Oh...and I use a heat gun to heat housings for new bearings to press into...

 

[_RG_]

Thanks Ghost! That's some very useful info. I've replaced the final drive oil once. Sounds like that was just a good start. That seal, is it the one on the drive shaft as it enters the final drive gear box from the engine side? My rig has 50K miles and now I'm wondering if replacing that seal would be wise PM.

Is that front wheel bearing another sealed "lifetime" bearing? I've just never pried the seals off a bearing. Guess that's kinda like all my mattresses that still have the "do not remove this tag" tag attached...

 

[ghostrider1964]

Thanks Ghost! That's some very useful info. I've replaced the final drive oil once. Sounds like that was just a good start. That seal, is it the one on the drive shaft as it enters the final drive gear box from the engine side? My rig has 50K miles and now I'm wondering if replacing that seal would be wise PM.

Is that front wheel bearing another sealed "lifetime" bearing? I've just never pried the seals off a bearing. Guess that's kinda like all my mattresses that still have the "do not remove this tag" tag attached...

Not sure if you have a 1200 or 1150 but the 1200s have a seal on the right side of the hub under the black donut dust cover. It starts weaping oil there once it fails. Front bearings are supposed to be sealed...and I guess lifetimenow who's lifetime is another matter

 

[E.Marquez]

Thanks Ghost! That's some very useful info. I've replaced the final drive oil once. Sounds like that was just a good start. That seal, is it the one on the drive shaft as it enters the final drive gear box from the engine side? My rig has 50K miles and now I'm wondering if replacing that seal would be wise PM.

Is that front wheel bearing another sealed "lifetime" bearing? I've just never pried the seals off a bearing. Guess that's kinda like all my mattresses that still have the "do not remove this tag" tag attached...

It is a sealed bearing in front, and yes it was "greased for life" when manufactured. That is of course part of the friendly banter and debate.


Remove a single lip seal from a "sealed" bearing..
The caution is,, not to damage the seal lip that rides against the rotating cone.. So pry, poke, remove from the outer diameter of the seal.. as it is less critical.
Second,, do not deform or cause the seal to be twisted.. as that will alter the way the lip rides against the rotating cone surface.

Pack only enough grease to fill the cavities between rollers (or balls).. if you try and pack all of the open space with grease, the seal will likely push out in use.. as well as you cause extra rolling resistance.. and can cause the grease to overheat (if it goes above it's melting point, you loose lubricity and the grease will "melt out" of the bearing. )

 

[_RG_]

Sounds like a good job for a rainy day...and I hope that happens soon.

Have y'all had any luck with these? Grease needle

 

[weekend_warrior]

To the OP Nice write up. The only thing I do different is use a heat gun and keep it moving on the hub until its hot enough to sizzle spit. Usually makes them way easy to punch out. I also freeze the bearing and heat the hub up again for inserting them. They pretty much push in with little tapping.

Just a word on the bearing "upgrade" kit from EE. The kit is not really an upgrade. They replace the stock parts with a little wider bearing. You throw the retainer ring away. Sounds good in theory. The seals fall out constantly while getting the wheel on. You need four hands to line up the brake rotor and keep the spacers in place. A little grease will help stick them in place, but made my KTM450exc wheel much harder to get on.

I'd spend the money for a stocky style replacement kit or the stock one. The press fit spacers rock....

That is all. Lift the seals and grease away if you must. Mine saw better than 380 hours before blowing out. I'd replace them around 300 and you be much better.... Mostly dusty conditions.