How often do you clean and relube your bearings?
How much grease do you use: a little or just pack them full?
How much grease do you use: a little or just pack them full?
Bearing maintenance?
- Thread starter JAB
- Start date
Good point. Should have written sealed bearings.
most sealed bearings are not user servicable, when they die, they die. If they were designed with a grease port it would be great, but it's pretty difficult to purge out old grease without taking the entire thing apart, which in some cases will ruin it or have a pretty big chance of ruining it.
Eh? I've taken apart cartridge bearings many times. You just have to carefully pry the rubber seal out with a razor blade. It's very easy.
I read somewhere that prying the caps away with a needle and using fork oil to flush out old grease was a good idea. Agree/dissagree?
Well I meant cartridge so in a sense what I wrote was correct.
I guess a needle would work too, probably with less of a chance of cutting the seal (if you cut the seal, you've just ruined the bearing). For me, a razor blade works pretty slick, and I use plain old dish soap and water, or Simple Green to wash off the old stuff. Not fancy, but certainly cheaper and less messy than fork oil.
Someone will probably tell me that I've been doing it all wrong and I'm ruining my bearings but I haven't had a problem yet
Jm, any reason you say that servicing a cartridge bearing ruins it? I can't possibly see how it would. As long as you're careful about not damaging the rubber seal....
I knew what you meant, I was just being preciseOriginally posted by JAB
Well I meant cartridge so in a sense what I wrote was correct.
I've used the razor blade many times to take the rubber cover off. If you take off both sides, it's really nice to use an air compressor to blow out all of the old stuff; just put a rag behind it so it doesn't go all over.
well remember i was talking about sealed cartridge bearings, and many times the seals are not really user-servicalbe, you try to take them apart, and you mess them up. Not true in all cases, but in many.Originally posted by binary visions
I guess a needle would work too, probably with less of a chance of cutting the seal (if you cut the seal, you've just ruined the bearing). For me, a razor blade works pretty slick, and I use plain old dish soap and water, or Simple Green to wash off the old stuff. Not fancy, but certainly cheaper and less messy than fork oil.
Someone will probably tell me that I've been doing it all wrong and I'm ruining my bearings but I haven't had a problem yet
Jm, any reason you say that servicing a cartridge bearing ruins it? I can't possibly see how it would. As long as you're careful about not damaging the rubber seal....
We're all talking about cartridge bearings.
The seals are always removable - otherwise, how did they get them in there? Sometimes they are in there more firmly than others, but with a little diligence, you can always get 'em out.
Just like any piece of bike maintinance, if you don't do it carefully, you'll mess 'em up. But you can do that to anything.
The seals in sealed cartridge bearings have a pliable metal backing that never really returns to new shape once removed and will allow some dirt to enter. That said, if your bearings are crunchy, you really don't have anything to loose. And if you keep greasing them regularly, you can get a pretty good service life out of them. On a bike with alot of bearings, you don't want to be buying new ones every season. If you pack them tight with grease, the excess grease will actually act as a seal to keep moisture out and trap the dirt before it can get to the race. Lube away.
I allways use wd40 and air from a track pump to clean them. A grease gun is invaluble for pumping grease back into them. I just pump them full but it oozes out in use so if you are in a dry climate you might want to just use enough to cover the bearings.
I wouldn't worry too much about damageing the seals, a little slit isn't going to affect the perfomance much and you can allways put the damaged seal on the less exposed side of the bearing. Usually worth a try as the only other option is to buy a new bearing.
As for removing the seals without damage it's just a matter of practice and using the correct tools. I find tiny watchmakers screwdrivers are best.
I wouldn't worry too much about damageing the seals, a little slit isn't going to affect the perfomance much and you can allways put the damaged seal on the less exposed side of the bearing. Usually worth a try as the only other option is to buy a new bearing.
As for removing the seals without damage it's just a matter of practice and using the correct tools. I find tiny watchmakers screwdrivers are best.
All cartridge bearings have this? Is it coated with the rubber? The cartridge bearings I've taken apart don't have a visible backing of any kind - they're the same rubber color as the front.
Hmm...
I think most, if not all, cartridge bearing have this metal backing. It is coated in rubber so you can't tell. Notice that if you bend the seal slightly that it doesn't return to shape?Originally posted by binary visions
All cartridge bearings have this? Is it coated with the rubber? The cartridge bearings I've taken apart don't have a visible backing of any kind - they're the same rubber color as the front.
Hmm...
Like I said, bearings are worth servicing, just be careful.
volkswagen guys do this on accesory belt pulleys. take out the pulley, pop off the seal carefully, repack with grease. and slap it back on and drive another 100,000 miles.
I figure that a belt pulley gets cycled 360 degrees for 100,000 miles. if the bearing seal can survive that than it can certainly survive the the movements from a bicycle suspension.
I figure that a belt pulley gets cycled 360 degrees for 100,000 miles. if the bearing seal can survive that than it can certainly survive the the movements from a bicycle suspension.
Hi,
The bearings on your Volks pulleys etc, are not subjected to the same loads as those on a mountain bikes suspension.
On an automobile pulley application the bearings while subjected
to much higher speeds, the load itself on the bearing is low.
On DH mountain bike the loads are much higher , imagine the weight of bike and rider of at least 200lbs and then subject it to some drops and you can easily see the amount of abuse bearings are presented with in this application is extreme given the size of the bearings in most cases. Now add a little dirt in the bearing and it makes matters even worse.
I am presently trying out some ceramic bearings on some of the pivot points on my Dh rig at the moment which are lighter and are supposed to excel in durabilty and performance, will see how well they last over time?
The bearings on your Volks pulleys etc, are not subjected to the same loads as those on a mountain bikes suspension.
On an automobile pulley application the bearings while subjected
to much higher speeds, the load itself on the bearing is low.
On DH mountain bike the loads are much higher , imagine the weight of bike and rider of at least 200lbs and then subject it to some drops and you can easily see the amount of abuse bearings are presented with in this application is extreme given the size of the bearings in most cases. Now add a little dirt in the bearing and it makes matters even worse.
I am presently trying out some ceramic bearings on some of the pivot points on my Dh rig at the moment which are lighter and are supposed to excel in durabilty and performance, will see how well they last over time?
http://www.xs4all.nl/~sotty/car/Grease_packing_Tool.html
Used this type of tool to repack many ball bearing (sealed) on my dirt bike over the years. Don't know how small they come in.
You do have to remove the "seals" they are not perfectly seales stock....that is why you get crap in them. If the bearing is jsut contaminated with grit...push fresh grease in and the dirty old stuff out with this. Clean up the excess grease and replace the "seals" and repeat when neccessary.
Rhino
Used this type of tool to repack many ball bearing (sealed) on my dirt bike over the years. Don't know how small they come in.
You do have to remove the "seals" they are not perfectly seales stock....that is why you get crap in them. If the bearing is jsut contaminated with grit...push fresh grease in and the dirty old stuff out with this. Clean up the excess grease and replace the "seals" and repeat when neccessary.
Rhino