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Hello Jon,

I have a 1996 Mk1 Pampera which has that year's trials wheels fitted. The rear wheel bearing has excessive play in the the sprocket side, but I plan to change both bearings at the same time.I have removed the circlips from both sides, but can not work out a way to remove the bearings as there is a tight tube spacer between the bearings. Can you please inform me of the best way to remove the bearings? Will it be the same procedure when I have to replace the front wheel bearings? Regards,

Peter K., U.K.

Hi Peter.

It's normal for the drive-side bearing to go first as the sprocket exerts more pressure to that side. The best way I've found to remove wheel bearings is to make sure the area around the outside of the bearing is as absolutely clean as you can get it. I then place the wheel on the ground and apply a little heat from a propane torch to the hub area surrounding the bearing. Use enough to get it warm but not too much as you'll want to apply some penetrating oil spray like WD40 around the outside of the bearing so it penetrates in between the hub and the outer race of the bearing. Be extremely careful as most oils are flammable. Putting the wheel on a plastic 5 gallon bucket will make it easier to work on and the bearing will be able to just drop out into the bucket. Unless you have a slide hammer and bearing attachment, you'll want a long, thin drift punch with the end ground flat so it has a sharp edge that will catch the bearing inner race. You may have to sharpen it a couple of times when taking the first bearing out. Carefully tap the inner hub of the bearing from the opposite side to drive it out slowly. Move the punch around the hub in thirds when tapping it so the bearing comes out evenly. A copper mallet, or other heavy, soft hammer works best because it delievers the pressure without the vibration.

After the first bearing is out, the other can be driven out of the other side with a socket and extension after removing the spacer sleeve that rides in between the bearings.

Before installing the new bearings, take a thin pick and carefully (so as to not cut the sealing lips) pop the seal off on each side of the bearing to expose the ball bearings. You'll be surprized at how little grease is in the bearing. Pack the ball bearings with a mixture of waterproof grease with about 30% anti-seize compound mixed with it. Carefully pop the seals back on the bearing and it's ready to install.

Make sure the hub is throughly clean and free of any corrosion. Smear a little anti-seize inside the hub, place the bearing on the hub and lightly tap aroung the bearing outer race in a circular pattern to get the bearing started in evenly. After the bearing is driven in most of the way, you can use a large socket and extension to finish the job. The socket should be just a little smaller than the outer race, so it applies pressure to the outer part of the bearing. By using the extension (a foot long one, if possible) you will be able to keep the pressure on the bearing perpendicular to the hub bore so the bearing doesn't get cocked in the bore of the hub. When the bearing is seated on the inner step, you'll hear the sound change a little. The tone emitted each time you tap the extention will change to a slightly deeper one when the outer race of the bearing bottoms out on the inner step of the hub. Don't forget to install the inner sleeve before putting the other bearing in. When putting the other bearing in, you can put the axle through the bearings so that it acts as an alignment tool to get the last bearing started evenly. I wouldn't use the axle as a driver even though it tempting. That will possibly damage the inner race and axle mating surfaces. You only want to apply pressure to the outer race when installing the bearings. The proceedure for installing the front bearings is essentially the same.

Hope this helps.


Professional tuner and 'Trials Competition' writer Jon Stoodley has very kindly stepped up to the plate to answer your questions. If you're having problems, or need some advice just send an email to Jon. If it's something that could be useful to others, we'll post it on the site.
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