Repacking the Bearings

Repacking the ole bearings amounts to 90% spent getting to the things and 10% actually pumping grease. Tools needed aren’t anything special and most folks already have the ones required. One exception might be a grease injection needle. Those are readily available from auto parts stores.

This is about the third go-round for me on this motorcycle and I’ve noticed each time that the sprocket side bearing consistently shows more wear than the brake side. Also, the sprocket side shows way less grease remaining than its counterpart despite both being replaced/repacked together. I guess that makes sense when you consider how force is applied to the wheel.

This is grimy job any way you look at it so a goodly supply of paper towels and some rubber gloves come in real handy.

There are a couple of “seals” between you and your bearing. Removing them without totally destroying the things is what we’d really like to do here. There are seal puller tools available and they work well - as do a couple of cheap screw drivers in this case.



Using one as a fulcrum and the other to pry up the outer seal is a matter of gently working your way around while making little – nondestructive – lifts. Eventually, it’ll pop right out and land some distance away before rolling under the heaviest appliance on hand. You needed to clean it anyhow…





It’s good to see a little grease here on the brake side. The sprocket side showed none. But, we’re still getting to that bearing and one more seal stands in the way. Clean things as you go along - it just makes the job more enjoyable, and besides, now you can see the next seal a whole lot better with it de-gunkified. A little squirt of acetone or brake cleaner helps a lot with the cleaning part.





This is when a small dental type pick tool is really useful. A tiny screw driver might work but we surely don’t want to tear up this seal trying to remove it from the bearing. It’s widely recognized that screw drivers love destroying seals. It lifts off the bearing with a little tug or so.



Behold… the bearing! Happily, we see some grease remains and the bearing feels fairly smooth when turned. That wasn’t the case on the sprocket side. It was pretty dry and catchy when turned. I fear its days are numbered.



This is the grease needle attached to your standard issue grease gun loaded with wheel bearing grease. The things actually work pretty doggone well.



The idea here is to push the needle down into the spaces between the bearing balls. Pushing to the bottom while pumping fills the lower half and forces grease up through the bearings. Again, just work your way around to each little space.



Cool eh? A thoroughly greased bearing. Rotate the bearing a couple of times in either direction to help distribute the grease inside before closing up.



Some folks - who actually know this stuff - tell me that too much grease is not necessarily better. Remove any excess from the bearing and clean up the seals as we go back together.



Resetting the seals back in place is easy. Here, I used some random piece of ¼” square bar and one of those weird dinky little Hobbit hammers. Wailing away on the thing is truly not required.



Same routine for the outer seal. Gently work your way around while humming this gentle tune. [ame="http://www.youtube.com/watch?v=hOA-2hl1Vbc"]Pachelbel’s Canon[/ame]

Clean off all the far flung grease from the brake rotor... if you plan on using brakes.



There ya go! All ready to go do some righteous rompin and stompin. And remember - “Ride today in such a way so as to ride again some other day.”

Thanks! I, uh, erh, need to do this.

Good job with the pics and narrative. I do this from time to time. The last time I had a bad bearing on the sprocket side also. I keep a set of seals on hand for when I mess one up getting it out. It is always better to find out you have a bad bearing at home rather than on the road or trail.

Thanks. I like that needle. I usually just put grease on top and rotate the bearings to get it in there. Needle is probably better.
At least I know I'm doing it right.
Any grease will do or does it have to be bearing grease? What's the difference with grease for my Jeep suspension ?

Don't forget to not mix grease types//// different types mixed can and will cause deterioration of the lube mix. Unless you're an expert in identifying grease types or have some tech reference that specs what grease was originally installed...Its best to start with a clean dry bearing and then add the grease of your choosing, and stick to it.

There is no such think as too much grease , I don't disassembly the seals to grease the wheel bearings , the needle on a flexible hose will slip under the seal of the wheel bearing with a little careful maneuvering and a magnifying glass these days . No roughness should be felt when rotating the bearing if it's not smooth it needs to be replaced with a quality bearing , not Chinese crap . The exception to this is a dirt bike when your not going to be hundreds of miles from your tools and truck to get spare parts . The only bike I have ever had to replace bearings on was my Cagiva after crossing the Devils river with two feet of water in it on my way to New Mexico by way of Big Bend many years ago . At the next tire change I could feel the roughness and replaced bearings that were fully packed before installation . I also pack the cavity behind the bearing separator inside the hub and the space between the outer seal and bearing they will keep any dirt and water from ever reaching the bearing . the rest of my bikes still have original bearings packed with good grease and ready to ride the world . A shot or two will be added to each bearing at tire change each time .
The people that claim too much grease is bad are the people that want everything to be spit and polish clean . since all my bikes are coated in a layer of bearing grease and slung off chain oil to the point that they are corrosion proof and only get washed at a major service time or when it rains and there hasent been any wax or polish in my shop for many years I'm ok with that . I tend to lean more toward long life and function rather than butt jewelry . SEYA

Hey guys I've been lurking & taking notes. RG I have a quick question. If Im going to break down these bearings is it going to be cost prohibitive to just use new ones, pack them with my grease choice & have new seals ?
I ask because I've not looked at the bearings & probably wont like what I see.

Side note. A group of us are meeting at CJs BBQ on 30 at noon today. See the piney woods bbq thread if your interested.

A trick I learned, was here in Fort Worth we have a place that sells bearings and you can take the old one in and. They can measure it and get you a better quality, not Chinese for about half the price..
The place is Purvis Bearing..

Cagiva 549 said:

There is no such think as too much grease

Click to expand...

Timken and most other bearing manufacturer I have ever read the tech articles from disagree.

A short snippet from a saved timken service doc I have at hand

"voids in a roller bearing should be filled from one-third to two-thirds with grease. Less grease will result in the bearing being starved for lubrication. More grease may create churning which generates additional heat."

Amount of grease
http://www.timken.com/EN-US/solutio...s3_Inadaquate_Grease_Lubrication_Part1of3.pdf
Mixing grease
http://www.timken.com/EN-US/solutio...s4_Inadaquate_Grease_Lubrication_Part2of3.pdf
Contaminated grease
http://www.timken.com/EN-US/solutio...s5_Inadaquate_Grease_Lubrication_Part3of3.pdf
SKF Amount of free space required in a capped bearing
http://www.skf.com/caribbean/produc...WT.z_oss_boost=0&tabname=All&WT.z_oss_rank=26

If the bearings last forever they can't sell you a new one , it's called planned obsolescence . It takes much more engineering to make a product last a set length of time verses making it the best you can . I went to the second school . And I expect my stuff to preform to my satisfaction . That's my biggest issue with computers , if the same brains had invented automobiles we would still be riding horses , and yes there is a lot of difference in grease quality , you won't find much stuff in my shop available in wallmart .

As far as the not mixing grease's goes I have a question.

I have neglected all my bearings...

I am getting ready to pull apart the linkage on my KX250, I am hoping I can just re-grease and get by for a bit longer. so how do I clean the old grease out so not to mix with potentially a different grease while repacking them?

Soak in gas? Parts Cleaner?

Or not stress to much since likely they're shot and need new bearing now or soon...

I buy varsol in 55 gal drums it does all my cleaning duties , a quick and easy choice is starting fluid for in place cleaning when you don't have time or the energy to do it right . Brake clean does very good too but I have seen it destroy plastic so use it with metal only . I dropped the swing arm out of my 04 950 KTM at 50 k miles to check the bearings and was amazed to see everything tight and clean just like new . I added some of my schaffers hi temp grease and put it back to work . In a chassis lube application mixing grease will not be an issue , in a heavy load high speed motor shaft bearing it will be an issue if you used cheap lithium soap grease , in any case some grease is better than no grease . I have three 60 hp electric motors setting in my junk pile right now with less than a thousand hours on them all with rough bearings and paint undisturbed on the grease fittings . I can't tell you how many machines I have seen run well over 10,000 hours with proper maintaince , in fact I remember pulling the swing arm on a new Husky and installing grease fittings in the swing arm bearings . All was still good when I sold it 15 years latter . If you buy a bike to ride for a couple years then peddle it don't wast your time . If you want many years of service from it you will need to give it some attention .

"It is always better to find out you have a bad bearing at home rather than on the road or trail."
^^^^^^^^^^
That's the honest to goodness truth.

Last spring one of the crew had a front bearing go bad while we were deep in the woods (Ouachitas). He had no other choice than to ride it out. By the time we stopped the wheel was flopping from side to side and the hub was totaled - as was the axle. Have you checked the price of wheels lately? Jiminy Crickets - take care of the ones you have!

Vinny, if you can press it in well enough by hand then it seems like the stuff is getting where it needs to be. I wouldn't begin to know the finer points of wheel bearing grease versus plain ole grease. I'm guessing there's a good reason for the distinction other than marketing, though.

DMux, that was really my purpose in writing this up. Help folks know that it ain't a big job, requires no special tools but is one of those motorcycle things we just gotta do. The alternative gets bloomin expensive. Of coarse, replacing all the hardware and seals will cost a few happy bucks. Repacking costs about 30 minutes and 13 cents worth of grease. If your bearings are shot then there really is no choice. If they're just a little dry then repacking can surely postpone that inevitable day when parts have to be ordered.

Freerider, I've always just soaked them in gas and used my wife's toothbrush to clean out the old grease - blowing it all out with an air gun afterward.

Eric, thanks for the info. I've heard from so many folks over the years about "too much grease" that there had to be more to it than witchcraft and superstition.

?agree
Have repacked on my trailers & car when I do the brakes. My fear is damaging a seal. I guess I could just get new seals if bearing looks good & I bugered a seal up.

_RG_ said:

"It is always better to find out you have a bad bearing at home rather than on the road or trail."
^^^^^^^^^^
That's the honest to goodness truth.

Last spring one of the crew had a front bearing go bad while we were deep in the woods (Ouachitas). He had no other choice than to ride it out. By the time we stopped the wheel was flopping from side to side and the hub was totaled - as was the axle. Have you checked the price of wheels lately? Jiminy Crickets - take care of the ones you have!

Vinny, if you can press it in well enough by hand then it seems like the stuff is getting where it needs to be. I wouldn't begin to know the finer points of wheel bearing grease versus plain ole grease. I'm guessing there's a good reason for the distinction other than marketing, though.

DMux, that was really my purpose in writing this up. Help folks know that it ain't a big job, requires no special tools but is one of those motorcycle things we just gotta do. The alternative gets bloomin expensive. Of coarse, replacing all the hardware and seals will cost a few happy bucks. Repacking costs about 30 minutes and 13 cents worth of grease. If your bearings are shot then there really is no choice. If they're just a little dry then repacking can surely postpone that inevitable day when parts have to be ordered.

Freerider, I've always just soaked them in gas and used my wife's toothbrush to clean out the old grease - blowing it all out with an air gun afterward.

Eric, thanks for the info. I've heard from so many folks over the years about "too much grease" that there had to be more to it than witchcraft and superstition.

Click to expand...

Plus 1 , trail side repairs are a pia . That is the number one reason to service your own bike , while you are servicing you are checking all this stuff , look for any loose stuff check adjustments on every thing that can be adjusted , spin each wheel , inspect the tires and inspect the chain . No kinks are allowed , no loose rollers , a side plate that looks bent or just plain worn out . Abnormal sprocket side wear or hooked teeth . I would be willing to bet money on it that every story of somebody on a trip or just weekend ride getting stranded with a broke chain could have been prevented it with proper inspection before the ride . It's way too easy to do it at home to take a gamble . To check for wear with the chain off the bike lay it on the ground and stretch it out , if you can bend it sideways in a C its toast also stretch it then push the ends to tighten it if it is a couple inches different its toast . With the chain installed grab the chain at the back of the rear sprocket and pull it away if you can see daylight between the chain and sprocket it's time to replace . The master link should be tight , any movement of any part of it other than the rollers is trouble I used to see master link clips safety wired , that's been a while . I love the rivet chains on my bikes . Bikes are not maintaince free , they do require attention if you want to enjoy your ride . And today looks like a good day for it .

High quality waterproof bearing grease is available at WalMart. Bearing grease is quite different than chassis grease. Your owners manual will give the spec on the grease needed for your needs. Use it.