Shimano in my case

How hard is it? And is it worth getting upgraded bearings and/or seals and if so where from?

Or am I better off buying complete new unit?

Newer shimano BBs are supposed to be much better than the older ones i.e 2006 and earlier. Although the Shimano ones aren’t that much cheaper than the Hope SS ones anymore, only a tenner or so in it.

To get them out you just remove the cup, wrap the cup in a bit of inner tube, clamp it in a vice and tw4t the old bearing out from the inside using a screwdriver and hammer. You’ll probably wreck the old bearing in the process. New one just pushes in using a vice and a smear of grease. 10min job.

Aftermarket bearings e.g. BETD/Enduro ones are much easier to clean out and repack with grease than the shimano ones and if you do this regularly they should last ages. Mine are 12months old and sill smooth.

betd also sell a nice and not ludicrously expensive tool to do it ‘properly’, or will do it for you for no extra if you post your cups to them. A mate bought five sets from betd to split between a few of us and they gave him the tool free. All five bb’s still spinning merrily (2 are in my bikes).

http://www.mountainbikerides.co.uk/fettling/hollowtech2bb.htm

Personally, i’d send back to betd and let them do it for £20 (including bearings)

Apologies for the minor hi-jack, but I’ve just had my cups back from betd (very quick service – posted my old cups to them on tuesday, received new ones friday) and am a bit mistified as to what to do with the 4 orange seals supplied (http://twitpic.com/94vfp.

The smaller seals clearly are the correct shape for sitting over the new bearing, but there doesn’t seem any clear way of them being held in place… anyone got any ideas?

Phil 🙂

2 of thoses seals go under the outer lip of the cup. There is a small gap between the bearing race and the outer – this is a mud shield and spacer for the crank (weel stop metal against metal) – I think they gave you 2 pairs as I can’t think where else you need to put them (1 on each side).

The seals are like the hope ones:

@foxyrider – I’ll take another look when I get back later, but I couldn’t see any obvious gap for them to seat in at first glance. Also, there are 2 pairs of slightly different sizes (presumably to fit differing brands of cups etc?), so I assume that I will use only the smaller one… Phil 🙂

phillj – the gap is fairly small on the hopes – NOPE

I see there is no proper gap – Erm I know perhaps that go on teh outside between the crank and the BB cup – if there is no gap that but be it? Anyone else?
Hmm – its similar to the spacer on my 105 Road set – that goes on one side I think the non drive sie – poss to act as a spacer – but that has the seals/wedge also?

Have a look here – STW Thread

Right BETD WEBSITE:

Swop out the old bearings and fit the new stronger new style bearing. The new bearings are nearly 30% stronger than the standard bearings. We get rid of that awful nylon shim and fit the bearing straight onto the Hollowtech II axle. It also comes with a better seal, if you want to use it as the bearings are fitted with rubber shields. It does help to keep the muck out. As an opening offer, for a limited time. If you send me your bearing cups i will change the bearings for you at no extra cost.

They go outboard! Enruto Bearing Replacement Blog

Its for the RaceFaces so some of it doesn’t apply but it shows you where to put the seal!

Aha!! Many thanks Foxyrider. After reading through the links supplied I found this… http://www.enduroforkseals.com/sitebuildercontent/sitebuilderfiles/hollowtech2a.pdf which explains perfectly what I’m supposed to be doing!! Result!! Many thanks 😀

only problem with the betd/enduro/hope bigger bearings is that once the bearings seize the metal on metal cuts into your axle adn writes your cranks off.

All crank manufacturers use a nylon tophat bush for a reason

You have been warned!

turnip – Member

only problem with the betd/enduro/hope bigger bearings is that once the bearings seize the metal on metal cuts into your axle adn writes your cranks off.

All crank manufacturers use a nylon tophat bush for a reason

You have been warned!

After 2-3 years of using Enduro bearings I never had a problem with seizing, imo the tolerance between the bearing and shaft is not tight enough to make them seize.

I’ve seen the top hats get worn through and wear through the axle (particularly poor maintenance there winston).

Just smack them out.

Leave the cups in the frame so you’ve got something solid to hold on to, and dunk the whole BB in boiling water for a minute or so. The expansion of the cups makes it much easier to knock the bearings out.