SHL M11-S (prototype)
Kieleckie Zakłady Wyrobów Metalowych has prepared a new model of a motorcycle with an engine with a displacement of 175cc for production. The engine of this motorcycle, which is a development of the S06 type construction with a volume of 150 cc, was developed in the Warsaw Motorcycle Factory. The SHL M1l prototype began trials in 1959. These motorcycles were aesthetically pleasing, with large side skirts, deep mudguards, and a high level of finish. A great achievement of the designers was the significantly quieter operation of the engine, thanks to the use of a new muffler and a different shape of the ribs of the head and cylinder, which eliminated the vibrations of these elements. In addition, there are many other improvements to the Mil model, such as a full drive chain cover, handlebar and toolbox locks, and a reserve fuel cock. The official presentation of the new models took place at the 29th Poznań International Fair in 1960. At that time, the production of the S'HL Mil was planned in two variants, differing in the solution of the front wheel suspension. The basic model had a medium push arm, while the M11-S model had a telescopic fork with oil damping. In fact, however, the motorcycle with telescopic suspension remained only a prototype, and serial production of the motorcycle in the basic version began in 1961.
Engine - Type S32, spark ignition, two-stroke, with backwash, rigidly mounted in the motorcycle frame. Bore 61.5 mm, stroke 58 mm. Number of cylinders l. Engine displacement 0.173 litre. Compression ratio 6.9. Maximum power 6.6 kW (9 hp) at 4800 rpm. Maximum torque 14.7 Nm (1.5 kGm) at 3500 rpm. Light alloy cast crankcase, vertically split. Ribbed cast iron cylinder. Ribbed head made of light alloy casting. Crankshaft forged, folded, supported on four ball bearings. Lubrication of the engine with a mixture of fuel and oil in the ratio of 25 : l. Air cooling without force.
Fuel: horizontal carburetor, type G24 Ul, throat diameter 24 mm, equipped with a starting device. Metal mesh air filter.
Electrical installation - Data as per SHL MO6-T.
Transmission - Data as per SHL MO6-T, with the following changes: Power transmission from the engine to the clutch with a single 48-link chain. Gear ratio 2.0 (34/17). Gear box with three ratios. Gears constantly meshed. Ratios for individual gears: Ib-2.89, IIb-1.47, IIIb-1.00.
Chassis - Data as per SHL MO6-T, with the following changes: front wheel suspension on a telescopic fork, with oil damping.
Braking and steering - Data as per SHL MO6-T.
Body - Same as SHL M06-T, with the following changes: Tool storage under the saddle. Sheet steel side covers to protect the carburetor, choke muffler and battery. Full chain guard, two-piece, attached to the rear swingarm. Lower exhaust system, with non-removable silencer, placed on the right side of the motorcycle.
Dimensions - Wheelbase 1290 mm. Total length approx. 1900 mm, width 600 mm. Height 960.
Weight - Motorcycle 114 kg. Permissible load 180 kg. Permissible total weight 300 kg.
Capacities - Fuel tank 13.0 litres (including 1 litre reserve), gearbox 0.8 litre.
Operating data - Top speed 90 km/h. Fuel consumption 3.0 litres/100 km. Other data as per SHL MO6-T.
Rafał Kozłowski (Żelazny) writes about the SHL M11 motorcycle:
The SHL M11 is really well designed and well made. It has never let me down on the road. The great quality of this motorcycle is evidenced by the fact that after 32 years of operation and 33,000 km, the crankshaft and its bearings do not show any wear. The same is true with the electrical installation. It is so simple that it cannot break down, but at the same time ensures proper lighting of the motorcycle. This is a really good bike and I recommend it to everyone who wants to travel around Poland but has little money. I assure you, this is really the best choice for Polish pothole roads.
Source: Polish History Archive