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View Full Version : Get more life out of your bearings!



Mosh
04-28-2012, 12:23 AM
One thing I have found through the years of riding and wrenching is that replacement bearings never seem to hold up like OEMS.
Why is that?
Well first off, with new parts come tighter tolerances. But we can't always help that, especially dealing with 25 year old machines. But maybe we can slow down premature bearing failure.
2nd, you get what you pay for..Buy those cheap Ebay $9.99 bearing kits with free shipping, that is what you get. I used to source bearings from a local electric motor supplier for a short time becuase they were cheap.. Well news to me.. 3 months later I was doing them again...Electric motor bearings are not made for the abuse of ATV suspension bearings, which is what you will probably end up with using "brand X". I wont go into details, because it is easy enough to google what bearing numbers mean for radial and axial loads and we all know that cheap isn't always better.

But what I did find over years of trial and error testing is interesting. There are 2-3 major Bearing suppliers for our market. I often wonder if they all get them from the same place for "Good bearing Kits"..?

Here I have a "major bearing supplier"..One who I will not put down because I have used many of their products with great sucess. I have also noticed this with other major suppliers too. So the defect appears to be steady or constant.
I have had good luck with the "name brand" parts..But even better luck with 10 minutes of attention during installation.

They always seem to be light in the grease department. No matter who makes them. After looking at them, they sit on a shelf. Probably in some hot warehouse. One side of the bearing is always wet with an oily substance. So before I put bearings in, I like to pop the seals and make sure there is sufficient grease. What I have consistently found is there is NOT. But why?
At the onset, I attribute this to a lack of efficient greasing, and also the fact that it "melts" as it sits on the shelf into some primordial ooze, and leaks out the seals towards one side of the bearing. By time we get them, they can be compromised.

So simple fix. Grab a sharp awl, or pick and pry the seals out on both sides. Add a suitable amount of water proof, all purpose grease and work into the bearing. Re install the seals..And good to go. Currently, I get "years" of service out of my bearings. I think I have had the "name brand" bearings in my carrier since 2008. Same with my wifes bike.

250Eddie
04-28-2012, 01:34 AM
speaking about bearings, I changed my front hub/axle bearings not that long ago id say 6 months maybe less and they are already super loose and shake alot. I put the all balls brand which from what ive herd is that they are good, what could be causing these to die after less then half a year, and which would you say would be the best choice.

yaegerb
04-28-2012, 01:44 AM
Excellent read, thanks for the information! Much appreciated!

KASEY
04-28-2012, 02:26 AM
speaking about bearings, I changed my front hub/axle bearings not that long ago id say 6 months maybe less and they are already super loose and shake alot. I put the all balls brand which from what ive herd is that they are good, what could be causing these to die after less then half a year, and which would you say would be the best choice.

i am going to say your bearing problem is self inflicted.... when you changed them,, did you install them without the ceter pipe? and then measure the distance between them and verify that there was no wear on the center pipe? probably not,, and then with a few thousandths wear you sideload the bearings and they do not last,,, its way more common in carrier bearings too,,,,,

250Eddie
04-28-2012, 02:35 AM
nah i never checked the length of the center rod inside, I no its in there but the weird this is that its only wearing on the left side, what i would could have caused this is, i originally put the bearings onto the wrong hub and didnt notice that the hub i put it on was a big red hub and they are longer then the SX hub, so i think the whole pain in the butt to get them back out might have tweaked it enough to do it.

Mosh
04-28-2012, 09:46 AM
All that info Kasey posted all comes into play for premature failure.
But if you actually had to remove and reuse that bearing again, that often is not done without some sort of shock to the bearing. So I would say that affected it. Also, lots of water riding, Wheelies, on a heavy utility machine, a bent axle, or tweaked forks can side load the bearings too much. Even a brake drum or rotor that is sticking due to faulty brakes, will overheat the bearings, and melt the grease out. Extended hi speed road riding will kill them fast too. We had a kid around here that bought a brand new 400ex when he was 15. He used it to ride the country roads to his friends house. In 3 months the brand new 400ex was in the shop getting new bearings from him ripping 10 miles a time, at 50mph. Especially rears, since the live axle does not like to turn on pavement.

WIkid500
04-28-2012, 10:01 AM
Hey Mosh. Good post. This brings a few things to light. Bearings are not supposed to be packed 100% full with grease. Imagine yourself running through water at shoulder height, then running through water at waste height, which is easier? The balls in the bearing are doing the same thing. Also over greasing causes high temps which could cause the grease to expand and push the seals out. The ooze coming out of the bearings you find sitting on the shelf is the oil separating from the thickener in the grease, this is why bearings have a shelf life. Also if you look into a pail of grease that sits for a while there will be oil on top, again this is the oil separating from the thickener that makes up grease. My $0.02

Mosh
04-28-2012, 10:18 AM
I agree that they can be over packed. Generally you see that on carriers with a grease zerk where people over grease.
But out of some hundreds of bearings I have installed, I have found more with insufficient grease, than ones with proper grease. I have actually found some name brand bearings with NO grease at all.
So I always make it a habit to look out of the box.

dirtface
04-28-2012, 11:16 AM
Mosh, definately great information. I have actually done this to hundreds of bearings that I have changed. Like you were saying there is usually only a tiny bit of grease on one side of the bearing, and sometimes none on either side. Good read, great info!