Make solid disc a floater

[thats_a_five]

I am glad to hear you have solved the problem.  From what you described, I can imagine the bearings were getting very hot as you rode.  That heat would transfer to the disc and ultimately to the brake pads and caliper.  That heating and cooling would lead to expansion and erratic brake performance.

 

So, did you pack those new bearings with grease before you installed them?  Factories put minimal grease in when they assemble bearings.  A good packing will not only lube the moving surfaces but also prevent water from getting to the bearing surfaces and causing them to corrode. 

 

Ride on!  And thanks for reading through my post and posting your answers. 

[b40rt]

1 hour ago, thats_a_five said:

 

So, did you pack those new bearings with grease before you installed them?  Factories put minimal grease in when they assemble bearings.  A good packing will not only lube the moving surfaces but also prevent water from getting to the bearing surfaces and causing 

http://www.belray.com/bearing-failure-due-over-lubrication

[thats_a_five]

Interesting read. Thanks.  You got my curiosity up so I have been thinking and reading about bearings for a few minutes. 

What I have learned there is a difference in failures between bearings in a relatively clean environment and bearings that get submerged in water frequently. 

Bearings in clean environments fail mainly from high vibration due to out of balance equipment or loss of lubrication (either not enough or too much grease as described in your article).

Bearings that go in and out of water regularly fail due to water causing corrosion of the bearing surfaces.  I excerpt some info from the “Bearing Buddy” site.  “The hubs on a boat trailer can heat up during long trips and when they are dipped into cool lake water, the sudden temperature change creates a vacuum inside the hub. This vacuum will draw any condensation, moisture, or impurities directly into the bearings, which can cause premature bearing failure.”  I think this could be more like the bearings on a trials bike.  They get heated when riding and applying the brakes.  Then dipped in a stream or even being washed with a stream of cold water from the garden hose or pressure washer will create that vacuum, sucking water into the bearing, leading to corrosion and bearing failure. 

 

Regardless how the bearings fail, I think the message is clear.  Check them periodically, at least yearly. Pop the wheel off the bike, stick your finger into the inner bearing race and see if it turns smoothly.  If it is stiff or rough feeling, replace it.  A few minutes in the shop will keep you and your bike happy in the field.

 

Cheers all!