Description NSU 1923 “4PS” 497 cc IOE V-twin frame # 428677 engine # 45667 The company started as a knitting machine manufacturer ( Neckarsulmer Strickmaschinen Union) and went into the bicycle trade in 1886. It was a logic step to move into motorcycle production and in 1901 the first motorised NSU bicycle with Zédel clip on engine was produced. Soon the development and production of the company’s own engines were taken up and the firm became one of the biggest motorcycle firms in Germany. NSU recommenced motorcycle manufacture at the war’s end with a range of 1914 models, pending the arrival of new designs. First seen in 1920, these were a 351cc single and 497cc v-twin, both of which were powered by ‘F-head’ (inlet-over-exhaust) engines. The 497cc twin was updated the following year when it was joined by a 995cc v-twin featuring a three-speed gearbox and all-chain drive. Although they were new designs, these early post-war NSUs represented the company’s past rather than its future, and as the 1920s progressed they gave way to a new line-up powered by side valve motors, commencing in 1924 with the 251R. The 4 HP model we present here has front and rear suspension and is fitted with NSU’s own two speed gear and clutch. These are fitted on the engine pulley and operated by a tank top-tube mounted lever. There are two brakes on the rear wheel, a foot-operated one that works with a v-block in a pulley, and a hand-operated one that works on the contracting-band principle. Accessories include Veigel speedometer, bulb horn, acetylene lighting system with Impex front lamp, Wittkop pillion seat and tyre pump. This sturdy vintage NSU comes in original, unrestored condition and will require some work before she can be used on the road.
