Help with a royce bottom bracket

[ishaw]

recently acquired one. But I'm not familiar with them at all aside from knowing they are very nice bits of kit.

I need some advice on a few things.

Bearings are rough and need replacing. I've removed them but not sure what to replace them with. Not wanting to cheap out, what would a good set of bearings be to replace them with, and what size?

I have the royce ti crank bolts, do they just fit as normal ones would?

The bb came with some alloy cups that I'm not sure what they are for? Any ideas? Pictured below, they are different heights.

How much of the bb is ti? Axle is, is the centre spacer? Cups I assume are alloy.

Are they designed for a set bb shell width or will they fit both 68 and 73mm?

Pics below, any help on rebuilding and fitting/maintaining gratefully received.

 

[Yogi bear]

Ooh lovely bottom brackets. I have at least four of them now.

They are titanium axle, everything else is aluminium.
Are shell width specific. The cups should sit flush to the bb shell, No lock rings are used.
I tighten the cranks on with steel bolts, then remove the bolt and replace with the Royce ones.
You can still get genuine bearings from Royce. Mtn bearings are readily available, but I can’t remember the size.
The alloy spacers are used when fitting. Holds the peg spanner into the cups as you tighten into the frame and prevents it from slipping. Use the crank bolts to hold it all together.
I remove mine occasionally and use an anti seize grease on the cup threads.

 

[hamster]

@yogi quick question - do you grease the interface between the bearings and shells? One of mine clicks under load...

 

[mdvineng]

For the bearing size, measure the OD and ID then the width. Use that to search online for replacements, they look like deep ball groove 2rs versions, so plenty about and cheap.

 

[My_Teenage_Self]

The bearing are 6903. I'd use SKF, NSK or NTN.

I spoke to the guys at roce about BB widths - they said that lock rings are not necessary (although the do supply them if people want them).

If the BB length is right, you could use a 73mm BB in a 68mm shell, but not vice-versa.

Use copper-slip on the bolt threads, Titanium is the king of seizing/locking.

 

[ferrus]

Re:

The Royce BB's without lockrings are notorious for creaking. Royce recommends their expensive anti-shake compound to prevent it and keep the cups stable, but I've found medium strength (blue) thread lock works well.

 

[hamster]

@ferrus thank you!