Historic Motorcycle Brands

MZ

 

MZ (Motorenwerke Zschopau GmbH) was a German motorcycle manufacturer located in Zschopau, Saxony. It was born out of the remains of DKW after World War II and traded firstly as IFA, before adopting the ‘MZ’ moniker in 1956.

 

1959-62 RT 125

 

To understand the impact of MZ it’s necessary to look back to 1939, when the company was DKW and developed the RT 125 motorcycle. This ground-breaking bike later became the most copied design in global motorcycle history. 

Copies of the RT 125 were built by at least eight different entities in at least six countries, thanks to post-War reparations that distributed German automotive brands to many allied countries. The best-known copies were the BSA Bantam and the Harley-Davidson Hummer. In Japan, Yamaha reverse-engineer the RT125 into its YA-1.

What made this ex-DKW bike engine so good? Throughout the 1930s DKW pioneered the Schnürle, two-stroke, loop-scavenging process to dispense with the use of a deflector piston and improve efficiency of the combustion chamber. 

Existing designs suffered from poor combustion quality, because if the two-stroke engine had a bowl-shaped combustion chamber above a flat-topped piston the overlapping fo inlet air and departing exhaust wasn’t optimal. If that poor mixing was eradicated by having a domed, ‘deflector piston’ the flame paths were inefficient. 

 

Schnurle porting from above – Andy Dingley

 

Schnürle’s solution was to dispose the inlet ports differently, so that exhaust scavenging was efficient and an ideal flat-topped piston could be used. That’s what the 125cc engine in the DKW employed to great advantage over competitor engines.

In 1948, the factory was owned by the East Germanyand was renamed Industrieverband Fahrzeugbau (IFA), a Communist-controlled umbrella foundation.  The disenfranchised DKW brand moved to Bavaria in West Germany, as part of the Auto Union. 

In 1950, the Zschopau works began production of the RT 125 model, branded IFA (Industrieverband Fahrzeugbau). 

1952, the BK350, two-stroke shaft drive was released and, in 1956, the works were called VEB Motorradwerk Zschopau, or MZ for short. 

Throughout the 1950s, MZ remained the world leader in two-stroke engines. On top of the patented porting MZ employed was an invention by the company’s racing engineer and department leader Walter Kaaden.

He added bike-maker ZPH’s rotary disc valve and asymmetric port timing that had been pioneered by Daniel Zimmermann. 

Kaaden began to further develop the expansion chamber invented by Erich Wolf that had first appeared on (West German)1951 DKW racers. In 1952 this DKW innovation was fitted to IFA racers.

 

Expansion chamber in two-stroke exhaust system

 

Kaaden used an oscilloscope to examine the resonance in the exhaust system and devised profiles to maximise the engine’s efficiency. The net result of this development program was that, by 1954, Kaaden’s two-stroke 125cc racing engine produced 13bhp – more than 100 bhp/litre – and was further developed to produce 25bhp at 10,800rpm.

The MZ engines became nearly unbeatable in the 125cc class, until Honda’s 2RC143 four-stroke twin took the honours in 1961, with Aussie Tom Phillis aboard. The Honda four-stroke had to rev beyond 14,000rpm to match the MZ’s output.

What happened then is more like a Cold War spy drama than a motorcycle design transfer. After months of planning that involved smuggling his family out of East Germany while he was abroad competing, MZ’s GrandPrix rider, Ernst Degner, defected to The West. With him went the secret of MZ’s success – Kaaden’s expansion chamber.

 

MZ RE 125 – Mark Scheider

 

Degner was immediately snapped up by Suzuki and the chambers were incorporated in Suzuki’s two-strokes. Degner won the 50cc world championship for Suzuki in 1962 and subsequent success followed in the larger engine classes. 

Much has been made of Degner’s ‘betrayal’, but cross-fertilisation of technology goes on all the time in the Free World. If he’d come from one Western bike maker to another, there would have been less fuss, we think. 

 

1968 MZ Enduro Team – Bundesarchiv

 

In 1963, MZ won its first International Six Day Trial and went on to repeat that performance in 1964, 1965, 1966, 1967, 1969 and 1987.

On the production bike front, in 1962, the ES 125/ES 150 was released, with an asymmetric low beam headlight pattern. 

 

1979 MZ TS 150 Luxus 22 – Hunniger

 

In 1970, the millionth motorcycle  – an MZ ETS 250 Trophy Sport – rolled off the conveyor belt and in 1972, MZ took over manufacture of sidecars from Stoye. A later sidecar version was powered by a Rotax, 500cc, four-valve engine. 

In 1983, the two millionth motorcycle – an MZ ETZ 250 was produced, featuring disc or drum brakes and 12-volt electrics.

 

MZ ETZ 250 – Thargor Wetton

 

MZ ceased sidecar production in 1989 and, following the fall of the Berlin Wall and the collapse of the GDR, the company waas privatised in 1990. However, its largely outdated product line failed to impress buyers and, in 1993, MZ entered receivership. 

The ETZ patent was sold to the Turkish firm, Kanuni, which continued producing the 251 and 301 models. In 1994 the factory produced the Skorpion range. Conceived by British design firm Seymour Powell, it used a 660 cc Yamaha single-cylinder engine.

Only after Hong Leong Group took over MZ Motorrad und Zweiradwerke GmbH in 1996 was there funding to invest in the development of new engines and motorcycles. 

 

MZ RT 125

 

The Group financed German MZ engineers to develop the MZ 1000 and improve the four-stroke MZ RT 125. Also, the Skorpion was followed in 2001 by the Baghira motard, which also used the Yamaha engine

The MZ 1000cc super bike was powered by an MZ-designed parallel twin that put out a healthy 117hp. It was an excellent performer, but was let down by fairly high pricing and a lack of dealer support globally. 

 

MZ 1000S Arrivisto

 

Following years of losses, the MZ factory in Zschopau closed in 2008, halting motorcycle production that had lasted 88 years in the same town. 

From 2009 until 2013, attempts were made to revive the MZ brand. In 2010 MZ started to compete in the new Moto 2 Grand Prix class, with Aussie rider Anthony West. In 2011, the MZ Racing Team had two riders, Anthony West and Max Neukirchner and West came so close to winning the first Grand Prix for MZ since the 1960s. 

During the 2012 season, MZ was afflicted by financial problems and had to withdraw from racing. The company itself closed in 2013.

 

2012 Ant West at Jerez on MZ 

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