Triumph NSD and Other Real Machines

What is the Triumph NSD?

You can read the whole story in Peter Cornelius’ excellent pages but, briefly, the NSD was made for 2 years from 1928 till 1930, or at least the vertical engine version was. Another Triumph NSD, initially labelled ‘deluxe’, with a completely different engine that sloped forward in the style of the popular BSA was offered in 1930 and 1931.
In the 1920s, a touring bike was a 350 or 500 cc, single cylinder, probably side-valve. If you wanted to pull a sidecar, you got and extra 10 mm on the stroke to give 550 cc, and a couple of lugs on the frame. A common arrangement was with engine vertical and forward mounted magnetos (or mag-dyno if you wanted electric lights). Gear change was by hand and throttle was a lever rather than a twist grip. There was probably no speedometer even though the national speed limit was 30 mph until 1930.

Some key features, then, of a Triumph NSD:
• 550 cc, side-valve, 5.49 hp
• Driven oil pump (but retained foot operated pump to comfort anxious owners)
• Saddle tank
• Total loss lubrication
• Drum brakes
• 4450 were made

The motorcycle industry at this time was served by manufacturers like Triumph, BSA, AJS, Matchless, Norton and Ariel aiming at volume production to offer low cost, reliable motorcycles for transport and leisure use. These and others had offerings for the ‘sports’ rider, some using JAP or Matchless engines with bespoke cycle parts. For ‘sports’ read ‘more discerning’ or ‘deeper pockets’. Triumph competed in both areas of the market.  I wonder if the prices in 1929 indicate specification and quality and give a clue to relative prices for these machines today.

From the 1929 Triumph sales catalogue:
1929 Triumph NSD with lamps and bulb horn £52 12s 6d
1929 Triumph NSD without lamps and bulb horn £46 17s 6d

Here are some prices from the 1928 Olympia Motorcycle Show for the 1929 machines:
Ariel side valve £43 10s
Coventry Eagle 346 c.c. ohv  J.A.P. engine £47 15s
Rudge Whitworth 499 cc 4 valve £49 10s
Matchless 495 cc two-port, guaranteed maximum speed of 85 mph £55
Triumph TT model, twin port 498 cc £66 17s. 6d
AJS K.10 498 cc £70
Velocette Model KSS is listed at £75
Brough S.S. 100 (with a guarantee of 110 mph) £160

The Motorsport archive is an excellent source this sort of historical information.

On 29 October, 1929 Wall Street crashed and depression but the brakes on everyman’s ambition for personal transport.  By the end of 1929, manufacturers were sharpening up their offerings and Triumph offered a no-frills NSD (stick on a bit of chrome, take off everything else) for £39 17s 6d, and they needed to move old stock – the NSD deluxe sloper that may have had a better chance against the competition was available.