Changing bearings on track hubs

Last thing I need to do with my conversion is change the bearings in the front hub. Its an Ambrosio Evolution and the hub is Ambrosio as well I think. Ive done the old lock nut and loose bearings type hubs before, but this has cartridge bearings so I havent a clue how to replace them. Just wondering what the people on here do when their hubs are gone.

To remove cartridge bearings you need to knock them out from the inside.

Easiest way is to strip off all the locknuts etc from the axle then use said axle to knock out the bearings. Thread a tracknut onto the end of the axle to protect and use a bit of wood twixt mallet and axle.

Have a rummage on t'interweb and you'll find quality bearings for much cheepness. Bear in mind you'll want 2RS (two rubber seal) spec fer weatherproofing.

Look out for SKF, FAG etc branded bearings.

cool, this doesnt sound too difficult. thanks for the excellent answer. Ill post a pic when Ive put it all back together

Hopefully the bearing spec will be marked on the cart.

If they're thr generic Ambrosio/Formula/Zenith/System-Ex branded hubs it'll be a 6000 series cartridge.

A quick Google for 6000-2RS will see you right for about a dozen sheets in total. Defo worth paying the tiny amount extra per bearing for quality branded kit. You could buy Phil Wood bearings if you fancy, but they're only Chinese 6000-2RS, unlikely better than any other premium bearing.

Good luck!

thanks, I'm going for a budget conversion but suppose its worth getting quality bearings if they last.

Is it possible to buy ceramic bearings for the same dimensions?

Hey James
if you haven't done your hubs yet, you can get Ceramic bearings for them. www.ceramicspeed.co.uk do a bunch of every type of best quality bearings ( made by SKF under licence for Ceramicspeed) - none of the cheap chinese junk there.
Last 10-20 times longer than steel bearings too.

dj

Hey James
if you haven't done your hubs yet, you can get Ceramic bearings for them. www.ceramicspeed.co.uk do a bunch of every type of best quality bearings ( made by SKF under licence for Ceramicspeed) - none of the cheap chinese junk there.
Last 10-20 times longer than steel bearings too.

dj

+lighter +stronger +smoother (less friction).

But . . .

On potential problem with the hardness of ceramic bearings is that instead of the bearings taking the wear (and then you replace them) - the races take the wear and then you must replace the hub !

arent we talking about cartridge bearings here?

arent we talking about cartridge bearings here?

very good point !

Ignore all the above !

I found this:
how to replace the bearings in your formula hub - Bike Forums
It has pictures of changing the sealed bearings in Formula hubs, I've been commuting since just before christmas on my formula's and I think the rear bearings need replacing, it sounds like something is rubbing near the hub on most revolutions, I popped the covers off the bearings and the look fairly well greased still but don't run silky smooth, I can't believe sealed bearings would have problems that quick, but I've regreased and stripped everything else to do with the transmission to no avail, anyway the noise is driving me mad so I've bought some replacement 6000-2RS bearings from ebay at 59p each and will see.

formula are budget hubs :(

it's true, it can happen.

I've had new hub bearings go silly after a very short time, at least it's cheap enough to replace with decent bearings.

of course, if a hub shell is badly machined it can mean the bearings don't sit properly and don't take the axle pressure evenly and so wear out, or get noisy quicker than they should.

Yeah I know they're pretty budget, they'll do for the daily beater, and another reason is I work in Shoreditch and I had my phils stolen, I was totally naive to fact the area is a hive of crack smoking bike theives.

Hopfully the 2 rubber seals will stand up to the weather conditions a bit better than the pony stock ones that came with the hubs

Hey James
if you haven't done your hubs yet, you can get Ceramic bearings for them. www.ceramicspeed.co.uk do a bunch of every type of best quality bearings ( made by SKF under licence for Ceramicspeed) - none of the cheap chinese junk there.
Last 10-20 times longer than steel bearings too.

dj

Ceramic bearings for skateboard wheels are about three times the price of the best steel ones. Then again they're BONES so I expect they're overpriced... Any idea if the same price difference applies to bike-sized cartridges?

These people list 6000-2rs bearings at between $2 and $250 a pair depending on material..
There seems to be a big difference between 'hybrid ceramic' ($10 ea) and 'full ceramic' ($60/125 ea) - not sure what it is.

Bear in mind that the lowest quality rated bearing (Apec-1) is designed to fail at not less than 32000RPM (That's 42 miles a MINUTE on a 700c wheel).. and that apparently quality of bearings is designed to give the bearing a higher fail speed, rather than less friction at low speeds.

I reckon I would rather get some cheapish name-brand bearings (SKF, etc.) and replace more often. To reduce friction, you could also think about getting -2RU or -ZZ bearings rather than 2RS.. this means that the bearing has a shield or seal, but the seal has a little gap in it and therefore does not touch both races (lack of contact = reduced friction, but less gack-proof). Also, different kinds and amounts of lubrication make a big difference to torque. I'd be interested in experimenting with some strange combinations and seeing how they run.

This page explains all the bearing variables quite well IMO.

ok, after just receiving the wrong bearings :( , i'd like to clarify the above!

ambrosio/system are 6000-2RS 10x26x8mm
phils are 6001-2RS 12x28x8mm

if you want some SKF version of the first lot for what i paid £3 PM me, otherwise they;re going back

o
phils are 6001-2RS 12x28x8mm

thanks for posting this - saved everyone else making the same mistake!

hmmm. part-ceramic bearings (ceramic balls, stainless steel race) are 10 times the price...
full ceramic bearings are 100 times the price of normal bearings. :-(

http://www.vxb.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=bearings&Product_Code=Kit8150&Category_Code=

White Industries ENO - 6902 - 2RS

There's a good tutorial here: http://projekto-b.blogspot.com/2008/01/how-to-replace-your-cartridge-bearings.html

The original bearings in the generic Formula hub aren't actually 2RS. They have one rubber seal and one metal shield (and like the rest of the hub, they're somewhat low rent).

I haven't found bearings to that spec, though...

If you're doing the job on a Formula make sure you've at least got new locknuts for the rear hub.

Better yet chuck the hubs.

Mine have now had new bearings, new locknuts and new tracknuts.

Buy cheap, pay dear...

hmmm. part-ceramic bearings (ceramic balls, stainless steel race) are 10 times the price...
full ceramic bearings are 100 times the price of normal bearings. :-(

http://www.vxb.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=bearings&Product_Code=Kit8150&Category_Code=

ceramic is overkill, no need for them on a bike really, it's just 'posh'.
Ceramic is useful in things like turbo's and superchargers, things that spin insanely fast and get really hot.
Your bike or anyone else's, won't have either so ceramic is a dead loss.

[edit] infact, i believe ceramic bearings were designed for turbos in the racing industry cos the steel bearings limited their potential.

kowalski, i was tempted by the metal sheilded ones instead of rubber, but they were only really really cheap ones, prefer to stick to the SKF!

...things that spin insanely fast and get really hot.

I run 69 GI and am unfit. so you're saying I *should *get ceramic bearings?

I run 69 GI and am unfit. so you're saying I *should *get ceramic bearings?

do your wheels spin anything near 40rpm ?