Wheel bearing question

[bikingagain]

So a couple months ago I noticed when I took my rear wheel off that the bearings didn't turn. I only had about 40 hrs on it but decided to replace them. I just now took my wheel off again and same thing, not turning. There is grease to keep water out, dust seals are on, they are seated well. What am I missing or doing wrong? Thanks
I assume I am stressing the rest of the drive train with it not utilizing the bearings.

[cedric]

Once the sealing surfaces of the spacers get grooved, it can be hard to keep bearings alive in there. I usually pop the seals out of new bearings and pack them with grease. The bearing guy told me that was bad for the bearings, but I feel that water and grit inside of them has got to be worse than any heat created by excess grease.

You do have the spacer tube in there between the bearings, right? You're not tapping on the inner races when installing are you?

When you remove the bearings again, pop off the seals and see what condition the inside of the bearings are in. If they're full of rust/grit/etc. then you probably need to replace the outer seals and spacers. This is also just one of those things that needs to be done every year or two, in my experience.

[cerealkiller]

How often are you greasing the bearings?

I don't remove the seals when greasing the bearings anymore. I used to, but it is very easy to damage the seal and allow grit and water inside. If you're really careful, I am sure it can be done.

Instead, I just pack the area outside of the bearing with waterproof grease to help keep junk out. I do, however, refresh the grease often. Like 1-3 rides, depending on how much water I rode through or if I "accidentally" sprayed the hub with the pressure washer. It's kind've a pain though. The rear wheel always seems worse than the front.

If you're replacing the bearings again, maybe try the ones that are sold with spacers grooved for seals. I think pivot works makes them.

[porschev]

Here are a couple things that work for me, but what do I know

I pop the shields off almost every bearing I've ever changed, using an o-ring pick for removal and my thumb nail to reinstall & have never damaged one.
Then I flush the sad little bit of grease the manufacture ships them with and then I repack them with a good quality waterproof grease. I've do this without spinning the bearing.

My thought is I'd rather have a bearing full of grease than one half full of grease & half full of water.
Regarding over heating due to to much grease while dirt biking, as I already proved to one member, its about as probable as seeing BIG FOOT on a ride, but who knows.

There is one mistake that I think a lot of guys make so it's worth mentioning that you should never mix greases. If you just add grease to a new bearing without flushing the original out, you are shortening the life of your bearing by quite a bit .

And Mike I'd be glad to show you how I install wheel bearings anytime!

[Bark]

Having worked for a bearing company for many years, I agree with the assertion that, for dirt bike riding, filling the bearing with grease is not going to cause any problems. The bearing manufacturers limit the grease quantity to allow the bearing to run at maximum rated bearing speed continuously without overheating and causing premature failure.

For a 6005 ('11 250XC rear wheel bearing size) deep groove ball bearing, the SKF basic rating is 9500rpm. If a dirt bike was going 100kph and the contact diameter is 25" (rough guesstimate), the wheel will be doing 835rpm at that speed. Ignoring load, thats not even 10% of the bearing's rating.

I'm lazy and I don't bother taking the shipped grease out. Most greases are compatible with each other. Cleanliness is more important than 'perfect' grease. Be as anal as humanly possible to keep it clean. Yes, the grease will heat up a bit and spooge out. But, I agree, more grease is better than no grease. I rarely get out of second gear so my rear wheel is doing like 100rpm.

As porschev notes, if you take the grease out with solvent, etc. try not to rotate the bearing without grease as you'll damage the bearings. If the steel is 'immaculately' clean, the steel balls/races will talk to each other and you'll damage the bearing. This is partly why I leave the shipped grease in. I add grease with a small syringe that I use only for grease.

If you want 'better' bearings, try the SKF Explorer bearings. They have better seals, quality, etc. I'd still add grease. That said, I cheaped out with an EE kit which included new seals, spacers and bearings.

Press only on the outer ring. If you put pressure on the inner ring, the bearing is garbage before you run it.

Those are my two cents...

[Jonny5]

Here are a couple things that work for me, but what do I know

I pop the shields off almost every bearing I've ever changed, using an o-ring pick for removal and my thumb nail to reinstall & have never damaged one.
Then I flush the sad little bit of grease the manufacture ships them with and then I repack them with a good quality waterproof grease. I've do this without spinning the bearing.

My thought is I'd rather have a bearing full of grease than one half full of grease & half full of water.
Regarding over heating due to to much grease while dirt biking, as I already proved to one member, its about as probable as seeing BIG FOOT on a ride, but who knows.

There is one mistake that I think a lot of guys make so it's worth mentioning that you should never mix greases. If you just add grease to a new bearing without flushing the original out, you are shortening the life of your bearing by quite a bit .

And Mike I'd be glad to show you how I install wheel bearings anytime!

Porcshev, How long do your bearings last after re-greasing them??

[erniebearskin]

I also just had rears go after less than 10 hrs?!?! First set lasted all of last year and this past winter. I'm assuming I installed wrong somehow for them to go that quick. Do you guys change spacers every time? Someone recommended that to me always new spacers with new seals.

Bearing woes..........

[malcolmzilla]

I like the all balls spacers that are aluminum with a pressed on steel seal face.

As mentioned, (re)pack the bearings and the seals with grease and clean an inspect regularly...

Use the correct driver or socket to tap bearings into the hub pocket on the outside race.

[bikingagain]

Thanks for all the great feed back. I only replaced the bearings so maybe a full kit will help.

[malcolmzilla]

I am running my Warp9 wheel set for the bush. It came with non anodized aluminum wheel spacers. 20 hours in they were grooved out and making a poor seal, despite being packed with grease on installation. I don't believe the anodized factory ones fare much better: a steel surface is much more durable.

[brentg]

Yes, full set all the time. The spacers do wear out and let stuff in. Installation is pretty important as well. Make sure they go in straight and true and make sure you are not hammering on them too much. I like to use expansion / contraction to my advantage. Usually I will put the bearings in the freezer overnight and heat the hub just before installation. If you do both, the bearings basically fall in place and then just need to be tapped down to make sure they are not cocked in the hub. I would not recommend opening and over-greasing any sealed bearing. I don't have as much dirt bike experience as most of the guys on here, but I do have more bearing experience than most people. Years ago it was common practice for millwrights to use a syringe to add grease to sealed bearings. Today, it is very rarely done because it can cause way more problems than it solves. On electrical motors, it most often leads to overheating a bearing and degrading the grease. It is true that on a very low RPM bearing, like a dirt bike, this won't happen. However, any heating will cause the grease to expand. Since grease doesn't compress, this expansion will put stress on the bearing seals and on your spacers. When the manufacturer 1/2 or 2/3 fills the bearing it is done to make room for this expansion. The balls also all need to be able to move in between the races. Over-greasing can limit this movement and make it harder to rotate the bearing. This robs power.

[porschev]

I run 2 sets of rims, my bikes 2010 and I'm just about to install my 3rd spacer sets & wheel bearings. Repack 2 or 3 times a year depending of where I've been riding.

This whole topic makes me giggle, everybody has to pay educational tax, some people just deserve to pay more!

[axel99]

I run 2 sets of rims, my bikes 2010 and I'm just about to install my 3rd spacer sets & wheel bearings. Repack 2 or 3 times a year depending of where I've been riding.

This whole topic makes me giggle, everybody has to pay educational tax, some people just deserve to pay more!

[calltrex]

stock spacers are no good. groove out easy.

my bearings blew up on the way home yesterday. Got the allballs bearing, seal kits

the allballs spacers are hardened steel

the allballs spacers also have a oring seal on the inside to keep water out aswell

[axel99]

The all balls spacers are no better than stock or the EE spacers. The plating on the thin steel ring wears off quickly and rust accelerates the wear. When the steel ring wears all the way through it rips the seal. The All Balls spacers don't last any longer than the EE in my experience. I have always found the stock spacers are the best just way too expensive.

Use a liberal amount of grease on the axel and where the spacers seat in the bearing inner race. Also make sure the aluminum spacer in the hub is not worn. If it is you will only get a few rides out of a new set of bearings. Do not pack the seals with grease just put a thin film on the sealing edges.

Make sure your chain is not to tight. Remove spacers after 4 or 5 rides clean the seals and spacers and let any moisture in the hub dry out. If the bike will sit for the winter and you have moisture in your hub plan to change your bearings in the spring.
Another trick with all spacers is to install the seal flush with the hub and when the spacers get grooved to the point you are concerned ,push the seal 1 or 2 mm further in the hub so it will run on a fresh part of the spacer.

Just what I do... I guess your mileage will vary