The Simson Star, type SR4-2, was a two-seat moped from Simson’s Vogelserie, built in Suhl from 1964. It was called SR4-2 until 1968 and SR4-2/1 from 1968 to 1975. With its foot-shifted three-speed gearbox and sporting looks, the Star became a favourite with young riders, and its 1200 Mark price made it the affordable sporty choice of the range.
Simson Star at a glance
| Maker | VEB Simson, Suhl |
|---|---|
| Type | SR4-2, from 1968 SR4-2/1 |
| Production | 1964–1975 |
| Engine | 49 cc fan-cooled two-stroke, M53 KF, 3.4 PS |
| Gearbox | three-speed, foot shift |
| Top speed | 60 km/h |
| Price when new | 1200 Mark |
| Frame | central tube with pressed-steel parts |
| Suspension travel | 105 mm front, 85 mm rear |
| Designer | Karl Clauss Dietel (SR4 range, from 1962) |
Based on one source, the German Wikipedia article on the Star.
History of the Simson Star
When AWO 425 motorcycle production with a four-stroke engine ended in 1961, the Suhl works could concentrate on mopeds with two-stroke engines. Alongside the further development of the SR2 E into the SR4-1 Spatz and of the KR 50 into the Schwalbe, the new M53 KHL engine laid the foundation for more models. It was designed so that it could be built with three or four gears and with hand or foot shift for different vehicles; with a three-speed foot shift it became the basis of a sporting two-seat moped called the SR — Simson-Rheinmetall — 4-2 Star. The name was misleading, since the engine never came from the former Rheinmetall works in Sömmerda but was made at Simson from the start.
Standardisation went beyond the engine. The central-tube frame with pressed-steel parts came from the Spatz; only the steering head differed, because the front wheel used the Schwalbe’s long-arm swing arm built into the mudguard, with 105 mm of travel. All Vogelserie models shared the wheels and drum brakes and the rear swing arm with 85 mm of travel. The tank was the same as the Spatz’s and, despite the knee grip, allowed a step-through. The handlebar and seat came from the Schwalbe, and the Star had the same full electrical equipment with a lead-acid battery, indicators, brake light, flasher and parking light. Its special feature was the new fan-cooled 50 cc two-stroke engine in foot-shifted three-speed form, type M53 KF, with footrests and kickstarter, which made it especially popular with young riders. The official top speed was 60 km/h to keep it in the moped class, although the engine had been designed as an “open” 50 and could go considerably faster under favourable conditions.
Production began officially in autumn 1964, though steady series output seems to have started only in 1965; either way the Star was the third Vogelserie model to enter production. Its retail price in East Germany was 1200 Mark, and it was not offered in West Germany. The SR4 range, including the Star, Spatz and Sperber/Habicht, was styled from 1962 by Karl Clauss Dietel. In 1968 the model became the SR4-2/1 with the improved M53/1 KF engine: power stayed at 3.4 PS but arrived at 5750 rpm, and maximum torque rose from 0.38 to 0.45 kpm at 5000 instead of 6000 rpm, greatly improving pulling power. The carburettor changed from the BVF 16N1-1 to the 16N1-6 and average fuel consumption fell by 7 percent, while the intake system, cylinder, crankshaft, kickstarter and fan wheel were also revised. The later cars can be recognised by a longer exhaust and a differently shaped exhaust pipe. After that the Star received only cosmetic changes, with previously light-coloured parts such as grips, headlamp rim and tank edging turned black.
Design and features
- Three-speed foot shift: the M53 KF engine gave the Star a sporting character rare among 60 km/h mopeds.
- Shared Vogelserie chassis: Spatz frame, Schwalbe front swing arm and common wheels and brakes.
- Full electrics: battery, indicators, brake light, flasher and parking light as standard.
- 1968 engine update: more torque at lower engine speeds and 7 percent lower fuel consumption.
Simson Star versions
- SR4-2 (1964–1968): the original model, with a narrow handlebar and round indicators in the early years.
- SR4-2/1 (1968–1975): the revised model with the M53/1 KF engine and a longer exhaust.
- SRA 50 Star (from 1996): a completely different small scooter that reused the Star name.
The Star shared its engine family with the Simson Schwalbe and its body with the Simson Sperber, whose engine was derived from the same unit. The later Simson S51 continued the sporty three-speed line. More vehicles are in the Simson collection.
Video: Simson Star Aufbau 2013
Video by Nick S. on YouTube.
Sources
- Simson Star, German Wikipedia: development, engineering, model update
