In this article I’m going to explain how to overhaul vintage mountain bike pedals. In this case the original vintage Deore XT pedals that came with my Koga Miyata Skyrunner Carbolite.
Video Tutorial
Step 1. Disassembling vintage mountain bike pedals
The first step is disassembling the entire pedal
Removing dust cap

A lot of older mountain bike pedals cannot be serviced but are sealed and not meant to ever take apart again. That is not the case with these high-end Deore XT pedals. They offer a similar style dust cap you find on cranksets, with a tiny opening where you can put a flathead screwdriver into to pry it off.
Before I was able to service the pedal I removed the part upon which your foot rests.
Removing lock nut

A mountain bike pedal behaves very similarly to a hub axle. This means that in this case loose bearings are held into place using cone- and lock nuts.

To remove this lock nut I hold the axle into place using a pedal wrench. Then I use a socket wrench to untighten the lock nut.
Removing cone nut

On top of the cone nut sits a small washer, which I pry lose using a flat headed screwdriver.
With the washer removed you have clear access to the cone nut. With the help of the socket wrench this can also be removed.
Removing axle and bearings
You can now remove the pedal axle. Be careful not to loose any of the very tiny bearings. With the magnetic tip of the screwdriver I’m able to remove the bearings that are stuck in the grease inside the pedal.
Step 2. Cleaning vintage mountain bike pedals
The next big step is cleaning all pedal parts.
Cleaning axle and nuts

I clean the axle and nuts using a small cloth or baby wipes. Remove all of the old grease.
Cleaning pedal bearings
I clean the bearings using my tried-and-true method of putting them into a jar with a bit of white spirit and swirl it.
If you don’t put in a ton of white spirit you can simply empty the jar onto a couple of paper towels. The white spirit will get soaked up by the towels, leaving you with the clean and shiny bearings.
Step 3. Reassembling vintage mountain bike pedals
Reassembling the pedal is basically the reverse of disassembling them.
Applying fresh grease

You start by applying fresh grease to both bearing races of the pedal. I don’t have a grease gun so I do it using my pinky finger.
Putting in the ball bearings
You return the ball bearings by pressing them into the grease. Before I return the axle I only do the side closest to the crank. With the axle in place I simply put in the remaining bearings on the other side.

Because the bearings are so small I use the screwdriver again to get them into the correct position.
The reason I do this is that otherwise you press the bearings out again, which just makes a mess of things. Don’t forget to grease the bearing race first or else there will be hardly any space left.
Tightening pedal cone

As I’ve said before, the vintage mountain bike pedal works the same as a hub axle. So tightening a cone means striking a balance between removing play and a smoothly rotating pedal.
This takes a bit of tinkering back and forth. Especially since tightening the lock nut usually means the cone might make the bearings bind into the race again.

If you’re happy with the result you can return the dust cap and reinstall the vintage mountain bike pedals on your bike.