Moto Morini 125T: the first Moto Morini motorcycle

Moto Morini’s first attempt at a motorcycle came from the DKW RT125, just like BSA’s Bantam. Yet despite a lack of experience, style certainly wasn’t forgotten…

Words and photos by Phillip Tooth

The DKW RT125 is probably the most copied motorcycle of all time. After the Second World War, the Brits used the little German two-stroke as the basis for the BSA Bantam, while the Yanks modified it and came up with the Harley-Davidson Hummer. The Ruskies stripped everything they could from the DKW factory in Zschopau and moved it to Minsk, where they used the tooling to make the Moskva M1A. Even the Japanese knew a good thing when they saw it and used the RT125 as the basis for the Yamaha YA-1 Red Dragon. Most of the clones were made as cheaply as possible, and they looked it. But the Italians have always done things with style.

Back in 1924, Alfonso Morini teamed up with Mario Mazzetti and they were soon producing MM motorcycles in Bologna, with Mazzetti in charge of design and production and Morini looking after sales and competition. The two-stroke 125cc MM Corsa won three Italian championships between 1926 and 1928, with Morini himself winning the 1927 Italian GP at Monza and setting six world records. MM grew fast, soon making ohv and side valve singles for the road, and overhead cam racers. But Morini and Mazzetti fell out in September 1937, and Alfonso left with 10,000 lire to start his own company – Moto Morini. It was not much, but by January the following year the fledgling company was producing 350cc, 500cc and 600cc side valve three-wheeler trucks similar to those made by MM. These had a motorcycle front end with a wooden box on the back and a payload of up to 1800kg. By 1940 the company employed 30 workers and was making three trucks every week. Moto Morini was also making components for aircraft engines when the factory was bombed by Allied aircraft in late 1943. That left Alfonso with time on his hands to think about what his company – or what was left of it – could make when war finally ended. For a motorcycle racer there was only one answer – motorcycles!

The most advanced two-stroke engine available for a road-going motorcycle was designed by DKW, then the world’s largest producer of motorcycles. The German company revolutionised the two-stroke when it bought all rights to the patented Schnüerle system. Before then, two-strokes used a deflector piston, with one large transfer port and one exhaust port on opposite sides of the cylinder. Sometimes these ports were split into several sections, but the intake charge was always prevented from exiting straight out the exhaust port by using a piston baffle or deflector.

The Schnüerle design uses a lighter flat-top piston and a group of transfer passages arranged in the cylinder liner to direct the incoming mixture away from the exhaust port. The classic Schnüerle port cylinder liner has one exhaust, one boost port (on the opposite side to the exhaust) and two transfer ports on either side. The result was higher revs, increased power, improved flexibility and more even firing.

The first of a new range of lightweight road models using the Schnüerle principle was unveiled in 1934 as the RT100 (ReichsTyp: National Type), and DKW soon dominated the production of inexpensive two-stroke motorcycles worldwide. Hermann Weber introduced the outstanding RT125 in 1939. With a 125cc two-stroke engine producing a claimed 4.75hp mounted in a single down-tube frame, with rubber sprung pressed steel front fork suspension, the RT125 set new standards for its class. The 125 went into mass production in 1940 but was discontinued the following year as resources were diverted to the war effort, although a Wehrmacht (Army) version was introduced in 1943 and remained in production until 1944.

Moto Morini’s version of the ‘Deek’ made its debut in early 1946. It was not such a blatant copy as the Bantam or Hummer but, like the German original, the Morini 125 T (T for ‘Turismo’) featured a three-speed unit construction engine with a cast iron barrel and alloy head. The bore and stroke were the same 52.0 x 58.0mm to give a capacity of 123.2cc, but the Morini’s cylinder barrel was positioned more centrally on a much bigger crankcase. The alloy crankcase was highly polished; labour must have been cheap. Transmission ran via a chain primary drive, multi-plate clutch, unit construction three-speed foot change gearbox and exposed chain final drive. While the prewar RT125 used a rigid frame, the Morini featured plunger rear suspension, with the springs enclosed in rubber gaiters to keep grease off the shapely legs of the bella donna sitting side-saddle on the carrier.

Forks were pressed steel, but instead of the Deek’s rubber band suspension the Morini used a chromed compression spring. Both wheels featured half-width drum brakes with alloy brake plates featuring water deflectors – the Morini factory was in the heart of the Bologna foundry industry and manufactured all its own castings. Ignition and lighting was taken care of by a flywheel generator. Of course, the Italian bike used a Dell’Orto MA16 carburettor fitted with a generous air filter, with 5% oil added to the petrol in the handsome chrome plated tank. Cycle parts were enamelled black, with green panels on the tank and the Moto Morini logo standing in front of a golden eagle – a more stylised version of the bird that graced the MM tanks.

The Morini certainly looks good, but how does it perform? The 125 T likes a rich mixture for cold starting, so the Dell’Orto float chamber is flooded and the choke closed. Then one kick has the stroker burbling into life. In the Italian heat, the Morini quickly gets warm enough to open the choke. Unlike a lot of older two-stroke singles, it runs clean at low speeds without a hint of four-stroking. A large megaphone-shaped silencer with a fishtail end keeps the exhaust noise down to an excited burble, although removing the end section might liven things up. The clutch is one-finger light and the three-speed gearbox, with its heel-and-toe pedal, changes cogs with precision.

With a compression ratio of 6:1, the claimed power output is 4.5hp at 4500rpm. Even though the bike only weighs 84kg, that is barely enough to pull the skin off a rice pudding and the Morini runs out of puff at about 75kph (that is a guess as there is no speedometer). It may not have been a roadburner but in those early postwar years petrol was rationed and so the fact that the Morini covered over 40km on just one litre was probably more important to most Italians.

For 1947 Moto Morini introduced a Sport model with a red and chrome tank, a 6.5:1 compression ratio, and a few minor tweaks. This was enough to increase the power output to 5.75hp at 5800rpm and push the top speed to 85kph. But, like the German original, the Morini stroker had huge tuning potential and a Competizione (racing) version capable of 125kph took the 125cc Italian championship in 1948 and 1949.

The company was struggling to keep up with demand as sales of the Deek copy exceeded Alfonso’s wildest dreams. But, of course, road riders always want more performance and so a 100kph Super Sport version with more generous finning to the head and barrel and a 20mm Dell’Orto was added to the line-up.

Although Alfonso Morini tweaked and tuned his two-strokes, other Italian manufacturers were building more exotic 125cc motorcycles. Bertoni came up with a vertical twin two-stroke, while Mondial took four world records with its beautiful double overhead camshaft single. It was time for the Morini factory to develop its own four-stroke – first for the racetrack and later for the road. Meanwhile, the two-strokes carried on delivering a handsome profit until production came to an end in 1954.

Moto Morini had grown into one of the biggest motorcycle companies in Italy and could afford to employ the best designers and engineers. That meant it had the resources to build the unbelievably fast double overhead camshaft 250 singles used by Tarquinio Provini in the World Championship – he finished just two points behind Jim Redman and the Honda Four in 1963 – and the ground-breaking V-twins of the 1970s. And it was all thanks to that DKW-based engine.

Technical Data – Moto Morini 125 T

Engine: Single-cylinder unit construction two-stroke Bore x stroke: 52 x 58mm Capacity: 123.2cc Compression ratio: 6:1 Carburation: Dell’Orto MA16 Claimed output: 4.5bhp @ 4500rpm Electrics: Flywheel generator, 6v 12Ah battery, coil ignition  Primary drive: Chain Final drive: Chain Clutch: Multiplate wet Gearbox: Three-speed Frame: Tubular steel single down-tube cradle Suspension: Pressed steel girder fork with central compression spring, plunger rear Wheels: 19 x 2.50in steel rims front and rear Brakes: 140mm half-width drums with alloy brake plates Dry weight: 84kg Top speed: 75kph Fuel consumption: 40km/litre