Triumph 1921 LW Junior 2 ¼ HP 225 cc 1 cyl TS

Triumph 1921 LW “Junior” 2 ¼ HP 225 cc two stroke single frame #602153 engine # 5981 gearbox # 7071

The Model LW, also known as the Junior, and nicknamed the ‘Baby’ for it’s the baby of Triumph’s models, breaks new ground for Triumph at its introduction to the press at the end of 1913. It’s Triumph’s first two-stroke model but it’s a success right from the start. With its weight of around 60 kg, ease of (paddle) starting and low saddle height the model gains immediate popularity amongst District Nurses, Ministers of the Church, and schoolboys with wealthy parents: the legal minimum riding age at the time is fourteen. But soon other categories of riders are seen as prospects, according to the 1921 catalogue: “The Junior Triumph Lightweight 2 ¼ h.p. is most popular amongst men of all ages. It is an ideal solo mount and so handy in city traffic it can be ridden quite as easily as a pedal bicycle. No more suitable mount can be found for the man who resides a few miles out of town and passes to and fro daily, or for the professional man. For the tour it’s extremely economical and a delightful machine to ride. “
Initially the 64 x 70 mm LW engine is of 225cc capacity, and although it has a tiny 2-speed gearbox there’s no clutch or kick-start. A clutchless gearchange is achieved by a swift opening of the engine’s pressure relief valve. Cruising speed is around 60 km/h. Production continues during the 1914-18 war years for the Model LW is also used on war service.
For the 1923 model year the engine capacity is increased to 249 cc by increasing the bore to 67.25 mm. Also a clutch and kickstart are added. The Junior is last catalogued in 1925.
The engine is lubricated via the “Petroil “system. The tank holds a petrol compartment and an oil compartment. The petrol filler cap doubles as an oil measure so the rider can add the correct proportion of oil. The 1921 catalogue explains: “ Oil is mixed with the petrol in correct proportions, so that every charge of gas drawn into the crankcase from the carburettor contains a proportion of lubricating oil. This oil separates under the compression and warmth of the crankcase, and in the form of oil vapour is thrown on to the bearings and cylinder wall. The petrol being volatile quickly vaporizes and passes to the combustion head via the transfer port.”
This very correct older restoration “miniature Triumph” comes with 24 x 2 ¼ tyres, Bosch ZA1 magneto, Brooks saddle, Triumph’s own double barrel carb and she has the correct typical Triumph nuts and bolts with integrated washers. She is sometimes referred to as “the motorcycle with the shortest plug lead (=20 cm) and the longest petrol feed pipe( =52 cm)”. For more than 30 years she has been part of the Honda Museum Collection in Japan. The engine is running, but some recommissioning may be required.