Triumph 1922 SD 550cc 1 cyl sv



Triumph 1922 SD  550 cc side valve combination  frame # 320156 engine #80638TRR

The SD (Spring Drive)  was in fact a somewhat modernised version of the famous model H, which had grown out of the “Trusty” veteran Triumph. 
By the mid-twenties belt drive was losing its appeal to many motorcyclists, so Triumph designed a model with chain secondary drive. 
The primary chain is protected by a well-engineered  aluminium case and runs in an oil bath to minimize maintenance of chain and clutch. The powerful 550 cc engine (bore x stroke =85×97)  has lots of torque. The machine is equipped with three speed  Sturmey Archer gearbox,   26×3 beaded edge tyres and  Bosch magneto. 
There are a full acetylene lighting set and a  rear view mirror board. 
The stylish sidecar is equipped with a windscreen.