Harley-Davidson U1200

In 1937, Harley changed the prefix on its side blowers and the Model J became the Model U. The side-ventilated models were available as the 750, 1200 and 1340. These were popular hardtails that were often equipped with a sidecar. I have taken a closer look at one of the 1200cc models, a Model U that belonged to the US Navy.

Side-vented Harleys have always been popular “workhorses,” and many have served their owners for a lifetime, often equipped with a sidecar. The fact that the U-models were preferred as sidecar pullers is due to the good torque of the side-vented engines.

In 1937, Harley modernized its side-vented models, changing the model prefix from Model J to Model U. The new U-series received a number of technical improvements. The frame was reinforced by adding double downtubes in front of the engine, and reinforced tubes in the rear of the rigid frame.

The gearbox was improved by getting new seals, and 4 gears were now standard. The engine was also upgraded with a dry sump (separate oil tank) and new cylinders with more cooling fins. In addition to these technical upgrades, the design was made more modern.

When the United States was drawn into World War II, the Harley factory in Milwaukee began relatively extensive production of military models. The best known is the side-blown WLA 750. In addition to the 750cc model, the American forces also used the Model U, which had a displacement of 1208cc.

• Technical data Harley Davidson Model U, 1942 model:
• Engine: V-twin SV (side valve/side ventilated)
• Displacement: 73.73 cubic inches/1208 ccm
• Number of gears: 4
• Power: 34 hp at 4000 rpm.
• Weight: 247 kg
• Top speed: 145 km/h