MZ 250 .

MZ 250 1960

1960 MZ. 250. Twice a "125" is a "250"—and that summed up the East German 250 c.c. twin-cylinder M.Z., for it was almost an exact double-up of the factory's successful 125 c.c. two-stroke as far as the engine was concerned. Each "half" of the motor had its own very deeply finned barrel and head and its own rotary inlet valve and crankcase cover with a carburetter and contact-breaker mounted on it.

An unusual aspect of the design was that the exhaust ports faced rearwards which, whilst giving a nice, clear exit path for the gases, must have made the barrels hotter in the port area than if they had been the other way round.
The engine was built in unit with a six-speed gearbox in which ten of the twelve gear wheels were carried on caged roller bearings—the other two were fixed to their shafts!

Reported power output of the machine was of the order of 42 b.h.p. (168 b.h.p. per litre), but this performance could be gained only at the expense of heavy fuel consumption, and the machines were fitted with 7gallon tanks.
Design-wise, the frame of the machine was fairly conventional, with twin down-tubes fairly widely spaced and pivoting-fork, rear end. In 1959 the models had employed their own leading-link forks and the steering and handling had been a cause of considerable anxiety to both the riders and the builders. So much so that for i960 Norton forks were fitted. Not a copy, but Norton forks, although the M.Z. factory's own hub and brake was retained.
Whilst the handling was improved, engine reliability wasn't, and all the M.Z. 250s retired in the T.T. that year.

SPECIFICATION
Engine: parallel-twin 250 c.c. two-stroke; induction by
rotary valve on each crankcase side. Ignition: coil.
Transmission: gear primary drive to six-speed gearbox;
final drive by chain. Frame: duplex cradle with pivoting-fork rear suspension. Forks: Norton telescopic.

MZ 250

MZ 250 1970

Italian, British, and Japanese motorcycle manufacturers all followed the lead of MZ and began to revive the two-stroke engine. Meanwhile the East German company continued to fight for the 125-class world championship.
MZ kept on with the 250 as well, but the company either did not realize what a fine vehicle it was or had drivers who did not adapt to it well. The motorcycle had plenty of power —45 h.p. at 10,500 r.p.m.—but it was defective in stability because of the encumbrance of the two cylinders on the side and because of the poor distribution of weight.

Ernst Degner and Walter Kaaden concentrated their efforts on the MZ 125 single-cylinder. In 1961 it generated 25 h.p. and had a top speed of about 125 m.p.h. That year Degner set his sights high. He was up against the big Japanese Honda team, which had very up-to-date four-stroke motorcycles that were ridden by the finest European racers.

The duel between MZ and Honda in 1961 went down in motorcycle racing history. Degner won the two German Grand Prix as well as the Italian Grand Prix at Monza. And at Hocken-heim he came in first followed by Shepherd, Fisher, and Brehme, all of them riding MZs. It was a dazzling team victory, but Honda won the world championship. The Honda was no faster than the East German 125, but it was ridden by top-notch racers like Phillis, Taveri, and Redman. After such an exciting season one might have expected MZ to press on, but MZ cut back instead.

The main reason for MZ's cutback in racing was the loss of Degner, the only racer who was considered good enough to ride the MZ to victory. He defected from East Germany and was immediately hired by Suzuki. The Japanese company hoped to learn from him the secrets of the fine MZ engines.

After Degner left East Germany, Alan Shepherd became MZ's number-one driver in the 125 class. But his chances of winning were slim because of the political tensions between the Communist bloc nations and Western Europe. More than once racing MZs were blocked at the customhouse and failed to gain precious points for the final classification.

The only bright note for the MZ team in 1962 was Mike Hailwood's second place in the 250-class competition at the East German Grand Prix.
With the same MZ 250 two-cylinder (with an improved cooling system using water, like that of the 1962 single-cylinder 125), Hailwood captured the 1963 East German Grand Prix, giving MZ its first win in that class. It was not until 1964 that the MZ had garnered another first place.

That year Shepherd, in his last season with MZ, won the U.S. Grand Prix at Daytona Beach in the 250 class.
At the beginning of 1965 MZ set its hopes on the 250, which generated 48 h.p. at 11,000 r.p.m. Because of the motorcycle's fine performance, the company thought about going into the 350 class, which it had raced in only occasionally.
A more powerful version of the 250 was built by MZ for that purpose, and Derek Woodman rode the new model in the 1965 world championship. It was the most competitive of MZ's three-cylinder vehicles. In 1966 Heinz Rosner joined the MZ team, but the results were disappointing.

MZ's failure was inexplicable. Every year the company began the season with technologically advanced vehicles, putting motorcycles into the field that only the Japanese could match. And every year they turned in only modest performances, despite the fact that the factory tests had promised more. The single-cylinder 125 generated 30 h.p. and the two-cylinder 250 generated 50 h.p.
Woodman and Rosner continued to race MZs in 1967. That year it was the 350 (actually a 300-cc, because the cylinder's thickness did not allow any increase beyond the original 250-cc.) which performed best. Rosner, who was a better racer than Woodman, won second place in Czechosloakia and captured third place in Ulster and Italy.

MZ fared much better in 1968, when Rosner (alone on the team) came in third in the world championship in the 250 class, fourth in the 125 class, and fourth in the 350 class.
In 1969 a new problem presented itself. The revised formula prescribed a two-cylinder, six-speed limit for racing, which should have worked to the advantage of MZ. Instead it turned out that the two-cylinder traditional-feed Yamahas, which were freely sold to private racers, were the motorcycles to contend with, in part because of the determination and ability of the men who raced them.

That year competition became tougher for Rosner, Braun, Bartusch, and Szabo, the racers who alternated racing official MZs in the three categories. And this notwithstanding the fact that the horsepower of all three models had been increased.

In 1970 MZ- had a 58-h.p. motorcycle in the 250 class, and the 125 engine was completely rebuilt. The same longitudinal axis had two water-cooled cylinders fed by two carburetors with rotating disks on the right side of the crankcase. The engine generated 32 h.p. at 13,000 r.p.m., but even this was not enough to beat such formidable contenders as Derbi and Suzuki.

Motorcycle: MZ 250
Manufacturer: Molorraderwerke Zscho-
pau, Zschopau Type: Racing Year: 1970
Engine: MZ two-cylinder, two-stroke, distribution through two rotating disks. Displacement 247.3 cc. (54 mm. x 54 mm.)
Cooling: Water
Transmission: Six-speed block
Power: 58 h.p. at 11,200 r.p.m.
Maximum speed: About 145 m.p.h.
Chassis: Continuous tubular double cradle. Front and rear, telescopic suspension
Brakes: Front wheel, central drum with four shoes; rear wheel, two-cam central drum

MZ 250 1972

MZs were constantly outraced by both official and private Yamahas in the 250 class and by the excellent Benellis, Yamahas, and MVs in the 350 class. They were also outclassed in the 125. MZ seemed destined to play only a minor role in speed racing.
The old team, captained by the East German Heinz Rosner, was disbanded, and hopes for the 1971 season rested with a new driver, the Italian Silvio Grassetti.
The first world championship race of the season was the tough circuit of the Austrian Grand Prix. In the 250 class, Grassetti was anything but a favorite. Nevertheless he outdistanced several Yamahas and came in first. Grassetti did not ride ip the West German, British, or Dutch Grand Prix, but he was back at Francorchamps for the Belgian Grand Prix. The MZ's 60-h.p. engine was exploited to the full, enabling Grassetti to win another first place in the Belgian race.
With the victory at Francorchamps MZ had its old name back, but the company was not ready for a full commitment to world championship racing. Grassetti rode the MZ again in 1972, but by this time the Japanese manufacturers and Harley-Davidson in the United States were so far ahead technically that the East German company's motorcycles had little chance in competition against them.

Motorcycle: MZ 250
Manufacturer: Motorraderwerke Zschopau, Zschopau Type: Racing Year: 1972
Engine: MZ two-cylinder, two-stroke, with rotating-disk distribution. Displacement 247.3 cc. (54 mm. x 54 mm.)
Cooling: Water
Transmission: Six-speed block
Power: Over 60 h.p. at 11,500 r.p.m.
Maximum speed: Over 150 m.p.h.
Chassis: Continuous tubular double cradle. Front and rear, telescopic suspension
Brakes: Front wheel, central drum, two-cam with four shoes; rear wheel, two-cam central drum