One of the most overlooked area's of most dirt bikes is the linkage bearings and swing arm bearings.
Why?
Probably because they aren't the easiest to get to and many people simply don't even bother with them.
Older bikes use to have Zerk fittings but few if any of the new bikes do.
On top of this it seems the manufactures have decided to vastly reduce the amount of grease they put in their bearings.
It almost appears that they use the grease that comes on the bearings but do not add any of their own.
I have seen some bikes only a year old with ruined linkage bearings.
So just a thought for all you new bike owners, GREASE your bearings before it's too late.
In this article I will show you how to replace your bearings.
In this example we are using a shock arm linkage from a 2000 Kawasaki KX500.
Here is the setup:
NOTE:
I already removed the dust seals on either side of the bearings.
To remove the seals you can use a flat blade screw driver and lightly twist the seals out.
I like to do them a little at a time using a circular pattern so that I do not damage the seals as you may need them at a later time.
This isn't the best picture but the small bearing area is shot!
The bearing literally fell apart when I removed it.
Yet, the hole in the aluminum linkage is not oval-ed out.
Before I removed the bearing I did one of the most important things, I measured the distance from the outside of the link to the outside of the bearing and recorded it for both sides.
If you are replacing the double bearing, then get these measurements recorded before you press the bearings out.:
I did this so that I would know how far to press the new bearing in.
This bearing is fairly easy to replace as it is centered in the hole so all you need to do is get it even on both ends.
The more centered you get it the longer and more even it will wear.
If you have a CLYMER or other manual, please consult it to verify your measurements BEFORE you start.
There is nothing worse then pressing in a new bearing only to find that it is the wrong width and now the seals don't fit.
The easiest way to get the old bearings out and the new ones in is using a press.
As shown below it's an easy set up:
Note that we used two sockets, one on either side of the arm.
The bottom socket is large enough that the bearing can easily fit through it and the socket is deep enough to allow the bearing to fall completely through.
Oh! You don't have a press?
How about a vice?
As long as you have enough jaw travel it will work as shown below:
As you can see, it is the same principal as using the press, it's just a little harder to get everything to line up.
The last method I have used is the "C" Clamp method.
It works just fine once you get it all lined up.
If you have three hands it is easier.
Regardless of the method used you should end up with something that looks like this:
At this point you should clean and inspect the aluminum bearing hole.
Making sure that it is round and not oval-ed out is a good idea before you order a bearing.
Ordering a kit is less expensive then ordering all the bearings one at a time.
If the linkage is oval-ed out you need to order a new one.
You can often find them on ebay such as the ones found here:
http://stores.ebay.com/OEM-CYCLE/_i.htm ... sid=680025
If yours is good I can't emphasize enough how much to clean it up.
