1948 Royal Enfield RE125 
Claimed power: 3.5hp @ 4,500rpm
Top speed: 45mph
Engine: 125cc air-cooled 2-stroke single, 54mm x 55mm bore and stroke, 5.75:1 compression ratio
Weight (wet): 130lb (59kg)
Fuel capacity/MPG: 1.75gal (8ltr)/130mpg
Price then/now: $325 (1948)/$2,500-$7,500

It all started innocently enough after dinner one Wednesday evening when I sat down at my computer and logged onto eBay. For some unknown reason I typed in “Royal Enfield motorcycles.” The first bike that appeared was a 1948 Royal Enfield RE125.

The seller’s description was short and to the point. He had purchased it from a garage sale near his home in Pennsylvania. He went on to describe the motorcycle as best he could and admitted that he knew very little about it. Never having seen an RE125 before I was curious, so I Googled the make and model, only to discover these little machines were very important to the British military during World War II, when they were nicknamed the Flying Flea.

Flying Flea background

The original design of this motorcycle was by DKW in 1935, a 98cc 2-stroke known as the DKW RT100, which went on to become the hugely successful and much copied RT125.

In early 1938, the Germans instructed DKW to cancel its relationship with its Dutch concessionaire, RS Stokvis en Zonen, after the Dutch company refused to force out its Jewish owners. Instead, the Dutch simply took an example of the DKW RT100 to Royal Enfield, asking them to make the same machine but with an engine displacement of 125cc. Royal Enfield’s chief designer, Ted Pardoe, was responsible for the faithful reproduction of the DKW RT with the increased 125cc engine size.

According to information I found, two prototype versions of the RE125 were displayed in Rotterdam in April 1939 under the name “Royal Baby.” World War II interrupted plans for civilian production after only a few were made, and the RE125 was instead manufactured for military use. The early version of the RE125 was nicknamed the “Flying Flea” by the British Army Red Berets parachute regiment in 1942 when it was released for service duty, where it was used extensively in airborne drops. The Flying Flea name fit perfectly, reflecting its light 130-pound weight and small overall dimensions; a mere 26 inches wide and 75 inches long.

The frame was constructed from steel tubing. Front forks were pressed steel girders linked top and bottom to the steering head by three rubber bands, a system designed by DKW in the mid-1930s for their racing machines. A 1950 revision of the front forks used a more modern telescopic style with internal springs for damping. A foot-operated gear change lever was also added at that time. Then, in 1951, the model was completely redesigned with a new frame and engine. Known as the RE2 to distinguish it from the earlier version, it was not enough to compete with the likes of the 1952 BSA D1 Bantam. With its plunger rear suspension and other modern amenities, the BSA was a more popular machine than the rigid frame RE125. In 1953 the Royal Enfield Ensign was launched, signaling the end of the RE125.