Triumph 550cc CSD SV (1929-32)
Triumph 550cc 1929 Model NSD
Triumph 500cc CTT OHV Twinport (1929-31)
Triumph 500cc CO Model (1929-31)
Triumph 500cc Type CN 4.98 h.p. Sidevalve (1929-1931)
Triumph 500cc Type TT Horsman
Triumph 277cc Model W
And others
The NSD 550 (549cc) has two quite different versions; the 1929 model has a conventional vertical sidevalve single; The next NSD model, released around 1931, is a sidevalve sloper with a finned crankcase. The ND 550 is very similar.
