About me. I build and repair Gyroscopes for a living. Have since I was 19 I am 46 now. I figure over my career I have changed around 40,000 bearings. some Highspeed applications like 22000-27000 Rpm bearings and some suspension bearings. suspending gimbals of gyros. I have analyzed a ton of failures. most have to do with contamination. some over tightening some shock damage. This is my opinion. these bearing have seals that are friction seals. they actually touch at the inside and touch at the outside. always sealed. then on top of that there are the wheel seals that seal around the shaft and bushings and the ABS plate (thingy) The wheels on this thing are basically a heavy Gyroscope, The reason Counter steer works. (Laws of gyroscope Science)
First: even with the right tools these were a bitch to get out. (I don't see any reason whatsoever to ever change these.) These will last the life of the bike and then also your life and maybe your grandkids
Because I am curious. I opened a bearing. New. and Old. Here is what I found. (for what it is worth)
This is the old bearing with 86,000 miles on it. The Grease isn't even dirty.
This is the new Bearing with zero miles on it.
This is the old one cleaned.
a bigger view
This is the inner race at about 10x magnification. I see very minor wear. no big deal.
This is the outer race at about 10x mag also.
and finally one of the balls. no pitting or anything. shiny enough to give perfect reflection of bench top.
