1937 BSA T74 Piled Arms Tandem with Watsonian Model No 8 Two-Seater Juvenile Sidecar


1939 Watsonian Model No 8 Two-Seater Juvenile Sidecar

I bought this Watsonian double-seat sidecar at an auction in Spring 2010, and restored it soon after. The original cosmetic appearance has been retained, but the plastic windows have been replaced.

I’ve not yet installed it on its bicycle: it’s easier to store separately. But I did fit it to the 1936 BSA tandem pictured below before that tandem was sold, so I could see how it looked.

The No. 8 double-seat sidecar was not made in great quantities, and it is very rare today.




The double sidecar will eventually be fitted to this 1937 BSA Piled Arms tandem

It’s not easy to calculate a BSA’s age from its frame number. The catalogues offer the best help.


BSA Bicycles & Tandems

Trade Prices for 1938 Season

According to the price list below, the Model number for this tandem in 1938 is T84.


I created a separate page for War Grade tyres – PLEASE CLICK HERE



By 1945, BSA tandems evoked memories of a prewar, peaceful England. An England where young couples took holidays together, cycling down quiet country roads and staying at b&b’s, hostels or inns.

BSA bicycles are notoriously difficult to date accurately. Frame numbers did not run sequentially, and few factory records or shop records exist. Catalogue descriptions are usually the only way to identify their age.

There’s little to distinguish Piled Arms tandems throughout their 1930s model years. The change of model number from year to year would appear to reflect only the new year’s catalogue model, eg T64 is 1936, T74 is 1937, T94 is 1939. I’ve only spotted a few changes from the catalogue descriptions.

If you compare the catalogues below, the 1934 tandem would appear to be fitted with a different gear trigger to the 1936 model.

In 1937 the Brooks ‘B15’ saddle was fitted as standard, replacing the Terry Leather Top saddle. This tandem has Brooks saddles, so I’ve dated it as 1937 accordingly. (Of course, saddles can be easily updated, so this tandem might actually be earlier).

The 1939 catalogue appears to offer only Cyclo gears.

A tandem is not mentioned in the 1940 catalogue, so I assume 1939 to be the Piled Arms Tandem’s final year.

This might become a reference point for these marvelous beasts. So I’ll continue my research and update this section bit-by-bit as I find out more.

1934 BSA Tandem Models T1 & T2

1936 BSA Tandem Models T61, T62, T63, T64

1937 BSA Tandem Models T71, T72, T73, T74

1938 BSA Tandem Models T81, T82

1939 BSA Tandem Models T92, T94

There were no tandems built during the war, a fact that BSA used in some of their wartime adverts. When you have leisure for pleasure again…

To see more bicycle sidecars