I always change wheel spacers with the seals and bearings if there is any sign of marking on the spacers.
IMHO, wheel bearings almost always fail due to s**t getting past seal etc.
Doing that ensures max life from new bearings.
Only two or three years as Honda used tiny 6202 bearings for the CRM
Doesn't matter what make it will wear out quickly, but being small they are cheap and it is more efficient and easier to replace them regularly as the time required for removal, cleaning, re-greasing and re-fitting costs more than replacement.
My Giant mountain bike still has the same wheel bearings it came with 12 years ago, never even looked at them, wish Honda used the same design.
Only two or three years as Honda used tiny 6202 bearings for the CRM
Doesn't matter what make it will wear out quickly, but being small they are cheap and it is more efficient and easier to replace them regularly as the time required for removal, cleaning, re-greasing and re-fitting costs more than replacement.
My Giant mountain bike still has the same wheel bearings it came with 12 years ago, never even looked at them, wish Honda used the same design.
I use 6202 bearings in my boiler work, fitted to fan motors that spin at more than 2000rpm, they also fit motorbikes, as Pete has stated. Don't think the bearings on your MTB would travel that fast
I always repack new bearings with motul grease before fitting, this IMO increases lifespan dramatically, I think jet washers and river crossings at the biggest problem for wheel bearings, leaving your bearings after washing with water ingress causing rapid rusting
Replaced with timken, new seals and zeta lipped spacers about 600 miles.
Replaced with koyo's smoothed off the original used spacers and fitted 1mm under size seals 2500 miles and counting.
Recently bought another bike supposed to have had bearings about 500 miles ago, they are worn out. Again I found lipped spacers. So I plan to file off the lip and fit tighter seals when I do the bearings.
I feel that seals that don't keep water out are brilliant at keeping water in.
Since I re-built the old KLX back in about 2010 ..... never had to replace a bearing. The 78 Husky 390 has had the same bearings for about the last 15 years, the Husky Auto was built about 3 years ago and has the same bearings still. The CCM has the same bearings I put in it 11 years ago.
As Dan said .... I use quality bearings (from Simply Bearings) and when I get them I remove the seals and wash out the pitance of grease in there. Re-pack with a good quality waterproof grease, and re-fit the seals. When fitting take care not to side load the bearing when knocking in. Only apply force to the outer when knocking in.
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Politicians are like nappies. They need changing often, and usually for the same reason.
I think fitting can be as important as the bearing. If you put them in even slightly angled or push them too hard and side load them they wont last two minutes.
I strip the bearings just like grouty- wrap them in clingfilm and put them in the freezer. Warm the wheel hub with a hot air stripper unwrap the cold bearing and drop it in. Often you can push them in with your fingers.. If one bearing has a retaining clip I usually put that bearing in first. Turn the wheel over and sit the bearing against the circlip. It will hold nicely when the spacer and second bearing goes in. Make sure they are square and snug.
Quality bearings are a must but all are vulnerable once the mud gets in.
-- Edited by mike on Saturday 31st of March 2018 05:01:43 PM