Back from a week riding at Glentress / Innerleithen and on giving the bike a good clean and fettle have discovered that most of the bearings are knackered.

I'm a bit disappointed because although the frame is 2 years old, due to young children / work etc etc it's not seen much use, (one week in the Lakes, one week at Glentress and perhaps another dozen or so half day rides). I'm always careful to clean and lube it well and never ever use a jet wash.

I have managed to extract all 8 of the cartridge bearings using various combinations of nuts, bolts and washers as make shift bearing pullers, without any damage to the frame. However there must be dedicated devices available for this job, any suggestions? My internet searching has only yielded tripod shaped things which I think are for pulling bearings off an axle, I need something to pull the bearing out of a recess (for next time).

Are the any dedicated devices for reinstalling the new bearings? I doubt a hammer is a good idea.

I understand the significance of the numbers on the bearing (6001 2RS etc), are their any particular makes to go for (SKS perhaps). The originals are single row deep groove ball type cartridge bearings, would a taper roller bearing be a better choice in view of the need to handle axial and radial loads?

Any help / advice much appreciated. The bike BTW is a Merlin Works 4.0 with an Ellsworth Truth back end.

James

Try a Google search for a 'blind bearing puller'

Rollers ake more sense but you'll not fit them in the bits of frame you've got, I think they'd be too wide. It is worth getting some Enduro Max bearings (BETD or CRC). They don't have cages in them but they've put more balls in. The theory being that the balls can move around more and even out wear instead of just rocking on the spot like cages bearings. In my experience, it seems to work. Deep groove balls are not the best thing for a rocking pivot application but they are relatively cheap and easy to find.

conversely raceface use max compliment bearings in their external BB's which typically last about 20 minutes, and are routinely criticised for it as being the wrong application

for example

http://www.peterverdonedesigns.com/bikebottombrackets.htm

Rollers would be better but as onza says they probably wont fit, and manufacturers dont spec them to begin with due to cost.

I use a large (12") G-clamp and assorted sockets to push in/out bearings on a range of bikes (FSR, Kona, I Drive, Giant) so have never got round to buying a dedicated tool. I usually advocate quality but SKF etc are multiples more expensive than ebayed cheap generic-branded bearings, and you can bet your bike came fitted with cheaper than cheap generic to start with, and I doubt SKF etc last multiple times as long. Spending the extra would be justifiable if you find fitting a big hassle for any extra time they do last. I pop off the seals on my linkage bearings every few months, clean and regrease, and in the process rotate/spin them to evenly spread the lube (takes about 10 minutes on the Kona). This probably inadvertently solves the localized rocking/fretting problem onza highlights. All ball bearings are essentially designed for high rpm low-load applications so most bike use is compromised, but the market has decided that simple bushes are too cheap a solution.

don't get confused by the fact that there are significant differences between what type of bearings suit BB compared to full sus rocker linkages.

Max bearings are great for rockers – having more bearings in contact is a good thing in this instance. (low wear due to limited movement, primarily needs to cope with high shock loads)

Max bearings are crap for Bottom Brackets – having more bearings seems t be bad in this instance. (needs to cope with high wear and thus high contamination risk)

WRT Roller bearings: You'll need to replace like-with-like. Cylindical roller bearings don't give any axial location, taper rollers need axial adjustment. Neither is suitable for suspension pivots unless you redesign the frame. And anyway, you won't find roller bearings with seals.

M-type bearings have a higher load capacity than caged, but to get a full complement of balls in they need a filling slot in both rings. That makes sealing a huge problem (a separate seal is needed), and they also won't take any axial load – hence Munqe-chick's experience of poor life.

In general, I don't recommend disturbing the seals. Each time you do this, you reduce the effecacy of the seal, so you're in a downward reliability spiral. It might be worth considering in a suspension pivot – if you can get at the seal without any disassembly – to eke out a little more life for minimal effort. But in a wheel, for instance, the effort of getting to the bearing makes fitting new a much better bet. If you do want to repack a bearing before fitting, only disturb one seal, and mount the bearing with the undisturbed seal in the firing line.

WRT fitting, MC's approach is sound. I would add that you need to be pressing on the ring which is tight. Ie. If pressing into a housing, apply force to the outer ring only, and press on the inner ring only if fitting to a shaft/stub. If both outer and inner are a press fit then you need a flat washer which covers both inner and outer rings. Never transmit force across the balls by pressing on the non-tight component. That just scraps the bearing immediately.

PhilO, I have accidently followed your advice by virtue of the construction of my suspension, the "top hats" being on the external side mean I can only remove the seal from the inner face of the bearing which is out of the way once assembled. Pushing a bearing in via the seal also knackers them 😳