Table of Contents
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1957 Sportster
Vehicle Identification Number (VIN)
- The serial number is stamped on the left side of the engine case. The first 5 or 6 digits represent the year and model 1)
The Sportster XL was introduced as “a modern, up-to-date power plant.”
In 1952, the W models were replaced with the revered 45-cubic inch side-valve K series. The new K-models included an integrated four-cam engine and four-speed transmission design, along with foot shift, swingarm rear suspension, and telescopic front forks to compete with smaller, sportier motorcycles coming mainly from Great Britain. Essentially, the new XL motor was an updated K-model engine with larger displacement, overhead valves and higher compression. - Harley-Davidson Archives Copyright H-D 2)
Number produced: 19833)
Original Price: $1103
Specifications
Engine
Capacities
Dimensions
Drivetrain
- Constant Mesh - Foot shift
- Speeds - 4 Forward
- Number of Sprocket Teeth
- Engine: 34
- Clutch: 59
- Transmission: 21
- Rear Wheel: 51
- Gear Ratios
- 1st: 10.63 to 1
- 2nd: 7.69 to 1
- 3rd: 5.82 to 1
- 4th: 4.21 to 1
Tires
- Front and rear: 3.50 x 18
- Tire pressure (based on a rider weighing app. 150 lbs or more)
- For each 50 lbs of overload, increase rear tire pressure by 2 lbs., front by 1 lb. 20)but not exceeding max tire pressure.
- Front: 14 psi / .96 bar
- Rear: 18 psi / 1.24 bar
Models
- XL
Colors
External Links
Back to Sportster History Index The Sportster XL was introduced as “a modern, up-to-date power plant” and weighing in at 2)
55cid 7.5:1 Compression, hemi-spherical style heads, 90 degree valve angle, OHV V-twin, 4 cams 4)5)
48 ft-lbs of torque at 3600 RPMs.
1-11/16“ Dia. intake valves 6)
3”x3.8“ bore and stroke
Piston Displacement (883cc) 53.9 cu. in.
Kickstart only
18” wheels standard
Speedometer designed into the sheet metal of the fork shroud.
Telescoping front forks
Fuel tank capacity 4.4 gallons.
Oil tank (3 quarts) located under the seat on the right side using a recirculating oiling system
Two brush generator w two-unit voltage regulator powering a six volt system
Coil-over shocks
'Jubilee' trumpet horn mounted on the right side of the engine, power pack on the left side
Paint color, 'HD 100' enamel
Standard solo seat
Options included
Windshield
Saddlebags
Dual seat
Front drum brakes (operated by a lever on the left handlebar)
Rear drum brakes (operated by a foot pedal on the left side)
Rear swingarm with Timken bearings at pivots.
Short-barrel Linkert Carburetor
Engine ID numbers on a pad located on the left side between the cylinders
Straight retained bearings on gear shaft
Roller valve lifters were called (High Speed Racing Tappets)
Spark plugs were air cooled and could be dis-assembled
Cams ramped on both closing and opening side
Stellite-faced exhaust valves
Aluminum alloy pushrods extend up through the covers to reach the rocker
Cam-ground aluminum pistons w/ chrome plated top ring, non plated center ring and u-flex lower oil ring
Aluminum rocker boxes enclose valves and rockers
Cast iron barrels and heads
Single-unit construction of engine and transmission
Four speed transmission with a foot shifter on the right side
Seven plate clutch (operated by a lever on the left handlebar)
Primary chain and transmission are lubed by an oil bath separate from engine oil.
Double tapered Timken roller bearings on sprocket shaft
Only Year:
Woodruff keys for camshaft gears
6 splines on drive gear/ second gear shaft
Choke control operated by a left side lever
Tank emblem: Round plastic disc with 2 silver and red quadrants with Red Harley-Davidson name over it, press riveted to the tank.