Norton ca 1925 model â16 Hâ 490 cc side valve single frame # 16165 engine # 13247 The 16 H engine with dimensions of 79×100 mm had a remarkable production run of no less than 45 years. Keywords with this design are reliability, robustness and power. The cleanliness and high level of finish of the engine are described in the 1924 catalogue as follows: âThe appearance of the Norton Engines at once appeals to the engineer. Of clean, sound design, no unnecessary protuberances, scrolls or advertisement appear upon them. There are no awkward interstices for the collection of dirt. All cover screws are sunk flush with the case, all corners are radiused and edges rounded. The special surface finish makes them very easy to keep clean and it is now generally recognized that, for smooth power production and efficiency, there are no better engines than the long stroke Norton.â For 1925 three 490 cc models were available, the standard â16Hâ, dubbed âThe Sports Nortonâ and clearly the fastest of the side valve machines (close ratio gearbox available on request!), the â17C Colonial Nortonâ that had among others a different frame with higher ground clearance, different tyre size and other gear ratios and the âModel 2 Touring Nortonâ, virtually identical to the â16Hâ but with footboards and semi-TT handlebars. This purposeful â16Hâ comes complete with acetylene lighting system. Sheâs is a very presentable older restoration and a good runner.