The S3B 3-Speed hub with 55mm Drum Brake.

I was handed an interesting little hub the other day.  I’d never seen an S3B before.  I checked the Sturmey Archer Heritage site to see what the date run was and to have a look at an exploded drawing.

The hub was made from 1967 to 1976.  The one I had in my hand was October 1967 so will be one of the first of it’s type.  They were primarily made for small wheeled bicycles such as the Moulton.  The exploded diagram shows no complications.  It is very similar in design to the AB using mostly the same parts but with a smaller brake.

I have been asked to fit a new sprocket, but there are some other parts missing which should also be fitted;  The sprocket dust cover is missing, the lubricator is missing and the RH cone lock washer is missing.  Also the driver is running very roughly.

I adjusted the RH cone and fitted a lock washer.  The hub is now running smoothly.

I have located a new 13-tooth sprocket on eBay which should be arriving any time now.  I’ll replace the missing dust-cover when I fit this.

A lubricator also needs to be fitted if we don’t want muck inside.  These are more difficult to find, but I have managed to get some of those too, so I will offer to fit one for the owner when I next see him.

The brake shoes are the only other part that may be an issue with this hub.  I haven’t checked them because the owner hasn’t asked me to, and I am unlikely to be able to get replacements anyway.

–

The sprocket has arrived and is now fitted.
According to the exploded diagram, this hub is not fitted with a sprocket dust cover, probably due to the extra thickness of the small sprocket.