The 1952 K Model was the first big Harley-Davidson with rear suspension. For 1958 the FL and EL big twins got sprung rear suspension and became Duo-Glides, boldly noted on the front fender.
This first year Duo-Glide is especially stylish in red and white with white grips and saddlebags plus whitewall tires. Continuing to give serious touring riders what they wanted, the optional King of the Highway package offered saddlebags, dual exhaust, fender tips, bumpers and either the Deluxe Buddy Seat or Solo Seat plus a luggage rack. As before, the “helper springs” flipped forward under the seat to provide extra support for a passenger, folded down for solo riding. In this era about 3500 FL’s and EL’s were produced annually.
The 1958 FL also received other updates including a hydraulic rear brake, a stronger transmission and clutch, better connections for the exhaust headers at the head plus optional white-wall tires. The chrome rear fender struts, already a design feature on the K Model and Sportster, became an element of the big twin as well supporting the rear fender and taillight. The rear fender remained hinged to allow for rear wheel service.
Although still available for sidecar use in 1949, 1948 was the last year the solo FL and EL Harley’s used the springer fork. The 1949 model was dubbed the Hydra-Glide and introduced the clean, sleek hydraulic fork with, in just the first year, gloss black-painted lowers. After ten model seasons rear suspension was added, and the big twin became the Duo-Glide but the big sprung seat, a tradition for comfort, was retained.
This classic Duo-Glide is on loan to the National Motorcycle Museum from Robert Hyler who lives in Illinois. It’s one of over 60 Harleys, street, racing and customs you will get to see when you visit the Museum. There is also a remarkable collection of Harley-Davidson memorabilia, signage and advertising graphics.
- Engine: Air-Cooled, Overhead Valve, 45 Degree V-Twin
- Bore & Stroke: 3.44″ x 4.00″
- Displacement: 74 Cubic Inches / 1208 cc’s
- Compression Ratio: 7 : 1
- Carburetion: Schebler
- Horsepower: 52HP
- Primary: Duplex Chain
- Transmission: 4-Speed, Foot Shift
- Clutch: Dry, Hand operated
- Final Drive: Chain
- Brakes: Drum Front & Hydraulic Drum Rear
- Electrics: 6 Volt Battery, Coil & Points
- Frame: Steel / Double Down Tubes
- Fork: Hydra-Glide, Hydraulic
- Rear: Swingarm / Dual Shocks / Sprung Seat
- Wheels/Tires: 5.00 x 16 / 5.00 x 16 Inches
- Wheelbase: 60 Inches
- Weight: 648 Pounds
- Top Speed: 100 mph