Launched in 1957 the Model Twenty One was the first of the Triumph unit construction twin cylinder motorcycles from the Meridan factory. With a capacity of 349 cc, the engine was a classic Edward Turner design with a 360 degree crankshaft, twin gear driven camshafts and twin plunger oil pump. The cylinder block was cast iron with an alloy head and separate rocker boxes. The engine was dry sump lubrication and there was a single Amal Monobloc carburetor. Drive was by a conventional four speed gearbox, with a right foot gear lever.
There are two explanations for the 'Twenty One' name spelt out in full on the side panels. The first explanation is that it celebrates the twenty-first anniversary of Triumph Engineering Co. LTD. The second explanation is that the important US export market rated motorcycle engine displacement in cubic inches and 21 cubic inches equates to 350 cc.
This example has received a Complete restoration about 15 years ago and has been used sparingly since. It is still in show quality condition. There is one small ding on the body that I attempted to capture a picture of. I believe a good paintless dent removal tech could remedy it. All of the chrome and stainless shows very well. All lighting and charging system functions properly. Engine and Frame are matching numbers original. Runs flawlessly with the exception of some smoking at start up that goes away soon after it is running. These bikes are ultra cool and rarely come up for sale here in the States.