Frank Berto, RIP

I am very sad to report that my old friend Frank Berto passed away last Sunday at the age of 90. He was the leading authority on the history and development of derailleur gears and the author of various books and numerous articles on cycle technology and its history. For more see: https://www.bikebiz.com/cycling-journalist-frank-berto-dies-aged-90/ and https://www.legacy.com/obituaries/marinij/obituary.aspx?n=frank-berto&pid=194780657

New content on K-series Sturmey hubs

If you go to the section of this website that provides detailed information on how to repair old Sturmey-Archer hubs, you’ll find new content on the K-series 3-speeds of the 1920s and 1930s. Not all the material is explicitly about repairing the hubs but it may prove useful and interesting to some readers.

There is now an 18-page PDF file (zoomable and easily printed) that includes all the following content:

  • The late great Jim Gill’s description of the type K hub and the changes made to it during its production run (2 pages).
  • A cutaway drawing of the 1922-1933 model.
  • Jim’s simplified instructions for dismantling and re-assembling the type K.
  • Jim’s analysis of the type K’s “no intermediate gear” feature, which went AWOL in 1935.
  • Jim’s tabulated analysis of 20 type K hubs manufactured between c.1925 and 1937 (2 pages).
  • S-A’s 1925 parts list and exploded diagram of the type K .
  • S-A’s 1935 exploded diagrams and parts lists for the type K, type KS and type KSW hubs (5 pages).
  • S-A’s 1937 exploded diagrams and parts lists for the type K, type KS and type KSW hubs (5 pages).

Go to the Cycling tab above, click on Gears and scroll down the list to “How to repair old Sturmey-Archer hubs”. Or just click on this link: https://hadland.wordpress.com/2012/07/02/how-to-repair-old-sturmey-archer-hubs/

Update 22 June 2016: I’ve also added material on the K-series brake hubs (KB, KC and KT) and on S-A’s 1930s drum brakes (BF, BR, BFT and BRT).

Major new cycle history interview

Interested in the history of Raleigh, Sturmey-Archer, Brooks, Pashley or Moulton? Or maybe in the wider development and changes the British cycle industry has undergone in the last 50 years? Then this interview, which I recorded on 23rd March 2016, is for you.

John Macnaughtan spent 48 years at Raleigh and Sturmey-Archer. Early in his career, he was sent to Raleigh South Africa and he soon became Director of Raleigh Industries East Africa. Later, with David Duffield, he set up Raleigh Australia. John joined Sturmey-Archer in 1977 and became Sales and Marketing Director in 1981. After the sale of Sturmey-Archer to Sun Race, he became Managing Director of Raleigh International. He was instrumental in saving the Brooks saddle company and became a co-owner of Pashley. Today, he spends much of his time at Bradford-on-Avon, dealing with the export of Moulton bicycles.

The interview, in two parts and full of unique insights and recollections, is now on the Veteran-Cycle Club YouTube channel.
Part 1: John Macnaughtan interview Part 1
Part 2: John Macnaughtan interview Part 2

2016-03-21 John Macnaughtan.jpg

New hub and bracket gear tables

You may have seen elsewhere on this site (in the comments on John Allen’s hub gear table in the Gears section) that Wiel van den Broek has created some very useful Excel spreadsheets for gearing choices involving hub gears and bracket gears. You can enter the tyre format, chainwheel and sprocket sizes and instantly compare the results given by different gears.

The gears covered range some more than 100 years old to others that are in current production. There is a metric (distance travelled per pedal rotation) chart and a gear inches chart (equivalent direct drive wheel diameter), both of which you can download from here: http://fietssite.jouwweb.nl/downloads

Many thanks to Wiel for creating these spreadsheets.

Tony

Sturmey’s right-hand ball rings: are you losing the thread?

Some instructions for disassembling Sturmey-Archer gears include a mysterious statement such as this:
“Next, unscrew the right-hand ball ring but because it has a two-start thread and must be replaced in its original position, that position must be marked. String or adhesive tape may be attached to the spoke nearest to the letters ‘SA’ which are stamped in one of the notches on the ring.” (From the 1956 Master Catalogue, sub-section 4, page 15, paragraph 1.)
The reason for replacing the right-hand ball ring in the same position is as follows. If the ring is screwed back in the alternative position, 180 degrees out from its original position, there could be some slight distortion of the completed assembly, due to a very slight difference of alignment between the hub shell and the ball ring. Whilst not noticeable at the hub end, it can result in the rim being slightly out of true. (The longer the spokes, the more the discrepancy is amplified.) So the precaution is in order to avoid the possible need to re-true the wheel.
This matter is not well documented but the rare 1992 Sutherland’s Handbook of Coaster Brakes and Internally Geared Hubs makes the point clearly. To facilitate correct re-assembly, Sutherland’s advises marking the ball ring at the point nearest the lubricator, rather than attaching tape or string to a spoke.
The reason for the two-start thread is to facilitate screwing the ball ring in relatively quickly, while having a stronger mechanical connection than an equally fast single-start thread would offer. For a given screw pitch, a two-start thread will screw in twice as fast as a single-start thread.
Tony