After 350km and some light shock loads the front and rear bearings (IBR-STAR) in Chosen hubs (Raleigh Pro Build) feel slightly gritty and notchy. Can’t remember how smooth they were in the beginning. Not sure if it’s normal or not since it has been said that hubs with spacers over axle joining two bearings together are designed to loosen when tightening QR sqever. Couldn’t find anything about these Chinese bearings in forums, or anyone complaining about Raleigh Pro Build CX/Road wheels in reviews. Only in the link below it says that they are high-end bearings.
​​​​https://www.nine-global.com/en/product.html

i`ve replaced teh bearings in my chosen hub. i cant remember teh sizes but i took them out and put the numbers on the seal into google and ordered new ones from simply bearings.

Were they gritty/notchy? Can’t see the reason to replace them yet, unless they disintegrate during the tour. So far all Chinese components in my cycling history have been durable enough. High quality parts are usually more delicate.

If they are the same hubs used on the MTB wheel builds with 120 point engagement hubs.

REAR AXLE
Drive = 6902 RS
Non Drive = 6002 RS

There’s 2 identical bearings in the freehub as well but I’ll have to look in my toolbox as I didn’t write down the numbers.

In terms of sourcing the bearings get them from a local trade supplier, rather than bike specific re-branding clownshoes. FAG, SKF, MTN and Codex are all decent.

if they are gritty and notchy they are fubar and need to be replaced. any bearing in decent condition should be totally smooth

I have been told that Chosen uses Taiwanese or Japanese bearings, so they can’t be that bad only after 350km. The only suspect is false brinelling caused by vibrations due to transporting the bike by train.
Another reason could be intrusion of metallic particles from pawls and engagement ring due to overgreasing noisy hub, but then then the front wheel bearings would be completely smooth.
https://www.etradeasia.com/supplier-2591/I-STAR-INTERNATIONAL-CO-LTD.html

I have been told that Chosen uses Taiwanese or Japanese bearings, so they can’t be that bad only after 350km. The only suspect is false brinelling caused by vibrations due to transporting the bike by train.

Naaa, they were probably just a bit cheap.

My Novatec’s felt rough after a similar amount of riding, but haven’t deteriorated. I’d probably swap them if I had a holiday or something planned. As above, just find a local bearings supplier (usually associated with gearboxes/transmissions or hydraulics) and get some known branded bearings. Not some bike-specific “our pink seals are worth 5W of drag and our blue grease was developed by NASA (for toilet o-rings)” nonsense.

This means that quite a lot of people are riding with compromised bearings without knowing it. It’s impossible to know how the bearings are behaving with tightened QR axle, unless one has a stethoscope.
https://www.bearing-news.com/slow-speed-bearing-monitoring/

It’s impossible to know how the bearings are behaving with tightened QR axle,

Nonsense – if you have a bit of mechanical sympathy you can feel / hear it as you spin the wheel.

The rear wheel bearings sounded like a smooth grinding noise when listening through the frame.

If you have a Chosen branded hub, chances are the bike manufacturer got it cheap thus it will have cheap bearings.

From your description the bearings are done and need replaced. Put decent quality bearings in it this time round.

Could replace but don’t feel ready for that kind of job due to planned tour/commute in 10 days time.
When listening trough Philips screwdriver placed between dropouts and end caps they produce slightly modulated hissing/howling sound when rotating forwards. When backwards there were some crunchy noises (could be anything). According to instructables article good bearings should produce “whisking” sound (maybe it was meant to be “swishing”). In case of insufficient grease there should be “sandy” sound,in this case it was more like hissing/howling. Old SKF stethoscope video shows only industrial bearing sounds in high speed applications.

If the ones on Novatec still aren’t detoriated then I might still use the original ones for a while then.

those bearings are on their way out. Replace them before your holiday or risk them failing totally. Bearing replacement is easy enough to do

-10-2018
“The bearings fail because they’re cheap and undersized. The axles flex which damages the bearings, making a quality bearing replacement not an option”
https://forums.mtbr.com/wheels-tires/chosen-sealed-bearing-hubs-1082866.html

I’m quite intrigued with this false brinelling suggestion. Taken further it should suggest we mount our bikes cyclocross style as they are moving to avoid static loads?

I’m not an engineer but I’m a bit surprised that even a flexy axle could flex enough to cause a problem.

If I were going on tour, I’d get them swapped out for some branded bearings from a reputable supplier (counterfeits are apparently quite common). I’ve used Wych bearings and simply bearings.

Can the bearings be just knocked out after pushing aside the sleeve/spacer found between the bearings. In a video about changing bearings on Novatec hub it was pushed aside by a finger. And it was said that the sleeve is gonna center itself, since it’s not there to apply preload, it just makes easier to guide the axle trough the hub.

And it was said that the sleeve is gonna center itself, since it’s not there to apply preload, it just makes easier to guide the axle trough the hub.

I’m familiar with Novatec hubs, and this doesn’t really make sense. The sleeve exists to prevent side loads on the inner races when you tighten the QR or axle: the QR clamps a stack of end cap/bearing/spacer/bearing/end cap between the forks. On QR Novatec front hubs, the spacer is kept centred by the end caps. On rear QR hubs, there’s an axle that the QR slots through.

Yup the sleeve should slide easily out of the way.

You have to use the hollow axle itself (block of wood against it) to bang the first axle bearing out as it’s locked in place (the axle) once both bearings are pressed in! It’s always the smallest axle bearing that’s **** and the most exposed (outside) bearing in the freehub, which means you end up doing all of them!

Take the end caps off, freehub and the non-drive side snap ring. Then all will be clear.

There are no snaprings/circlips in this hub. Probably will have to get some blind bearing puller at some point to avoid messing with the sleeve.
So the sleeve can be centered with the axle itself during the pressing of the bearings?
Shame lost the piece of paper with written down bearings sizes.

Got the bearings (15267 available only from Enduro) and tools not long ago. Probably will replace them someday before hypothetical extra long tour since the original ones are still usable enough.

134.5mm dropout spacing (advertised as 132.5mm) on Thorn Audax Mk3 doesn’t help either in case of a 130mm hub. .
“Justin (Burls, the frame designer) echoed what Dave said; the 132.5mm mid point setting would always stress the frame and the dropouts would never be parallel to the hubs.”
http://thorncyclesforum.co.uk/index.php?topic=7543.0