Campagnolo BB bearings

pinarellokid

Just fitting an Ultra Torque chainset to my bike and have a quick question.

I need to replace the drive side bearing and wanted to ask, if I get a bearing of rom my local supplier and ask for an
SKF £12 brand one will it be better quality than the ones the LBS sell at £25 ???

Price is really the same but is the quality better?

Also if I went down the SKF route I would have to use the old outer seal, which I don't like the idea of.

Does anyone know if you can buy the seals from somewhere?

Or should I stop messing about and just buy the Campag one from LBS

Cheers

ugo.santalucia

You can't... these are 37x25x6 and not the more common 37x25x7 so you won't find anything but the Campagnolo replacements or dodgy chinese ceramic jobs

Monty Dog

Yup, UT uses a proprietary narrow bearing so you have to use the Campagnolo ones

drlodge

Would an extra 1mm on each bearing *outboard* actually make any difference I wonder?

ugo.santalucia

drlodge wrote:

Would an extra 1mm on each bearing *outboard* actually make any difference I wonder?

I suspect the two halves of UT won't engage in the middle, where the UT bolt sits...

pinarellokid

Yep glad I asked now, you guys were right,

Better get the campag ones ordered then lol

drlodge

ugo.santalucia wrote:

drlodge wrote:

Would an extra 1mm on each bearing *outboard* actually make any difference I wonder?

I suspect the two halves of UT won't engage in the middle, where the UT bolt sits...

That would apply if the extra width was inboard, but outboard?

On the drive side, there is a clear gap to the dust cover, so only question is whether the bearing can be pushed a little further down the half shaft, then the cup retaining clip might not clear (I don't understand the purpose of this clip anyway, I can't see why its needed). On the NDS, the bearing would be pretty close to the dust cover and here it may not fit.

ugo.santalucia

drlodge wrote:

ugo.santalucia wrote:

drlodge wrote:

Would an extra 1mm on each bearing *outboard* actually make any difference I wonder?

I suspect the two halves of UT won't engage in the middle, where the UT bolt sits...

That would apply if the extra width was inboard, but outboard?

On the drive side, there is a clear gap to the dust cover, so only question is whether the bearing can be pushed a little further down the half shaft, then the cup retaining clip might not clear (I don't understand the purpose of this clip anyway, I can't see why its needed). On the NDS, the bearing would be pretty close to the dust cover and here it may not fit.

They are already pushed al the way in, you can't push them any further... you might clear a bit of room removing the wavy washer, but only on one side... the only solution would be to machine the BB cups 1 mm deeper.
However, it is worth trying on the left arm without the wavy washer, considering 9 out of 1 the left bearing is the first to go

gfk_velo

You need to use the Campagnolo bearing because the generic 7mm deep bearing doesn't allow the fitting of the c-clip on the gear side. There is no c-clip on the NGS.

The purpose of the spring clip that sits in the gap left between the chainwheel side of the GS bearing and the lip seal that side is threefold - it prevents the GS bearing being pushed out of the cup when the two haves of the Hirth joint are being mated on assembly (which is why Campagnolo suggest it should be installed immediately after the GS "half" of the assembly is fitted into the GS cup), it will prevent the chainset dropping out of the GS cup in the event of the failure of the Hirth joint and last, it limits the side to side movement of the completed assembly.

The purpose of the wavy washer is twofold - it compensates for the lack of accuracy in the manufacture of most BB shells by allowing an error in width of up to 1.6 mm (Campagnolo's dimensional tolerance is =/-0.8mm on a 68 mm shell in case of BSC or 70mm in the case of Italian - the 2 mm nominal shell width difference being taken up in the depth of the cup bores) and it allows an element of automatic adjustment whilst correctly pre-loading the bearing. Therefore it should not be missed out.

If a mechanic were to use the generic bearings, miss out the C Clip, the DS circlip and the wavy washer as suggested by santalucia and the BB shell to be at the high end of the width tolerance, quite apart from anything else, the Hirth joint might not fully mate - in which circumstances it would eventually fail.

The UT design is pretty robust so long as the frame is correctly specced and prepared, the bearings are mounted the right way around, the cups are charged with grease (in the case of the "normal" Record bearings (FC-RE012) and swiped with grease in the case of SR) and spray lubes / degreasers are kept well clear of the BB area.

All of this, bar our observation with regard to spray lubes & degreasers is in the Campagnolo instructions and tech manuals, but we still see lots of incorrectly serviced UT in the market.

HTH
Graeme
Head tech, Velotech Cycling Ltd | Campagnolo Main UK Service Centre.

cycleclinic

Well good thing it good thing I did the chors U-T the way Graeme has sggested. I just thought it had to be done this way.

Interesting point about the spring clip I wondered why it had to done the way campag suggested.