Ironhead Sportster (1972-1977)
To keep up with the litre-bikes that Japan was offering, the Sportster got a bump in motor size in 1972.
Boring the cylinders 3/16ths of an inch brought displacement from 883cc to 997.3cc (advertised as 1000cc). The increase also gave a more optimum bore-to-stroke ratio, resulting in a smoother running motor. Power was also increased, pushing top-speeds past 110 mph. Quarter-mile times dropped into the mid-thirteens, and by removing the stock exhaust baffles, another half-second could be gained.
The 1972 Sportster saw other minor changes. The Tillotson carburetor, prone to vapor lock when the engine was hot, was dropped in favor of a Bendix unit. The new carb also sat closer to the motor, causing less of an obstruction to the rider's right knee. The magneto ignition used on the XLCH models was gone, in its place was the points/coil/battery system from the XLH. Sales nearly doubled from the previous year, with just under 18,000 units sold.
1973 Sportster
Sportsters were upgraded from front drum to a single front disc brake in 1973. The same year, turn-signals became mandatory on all motorcycles sold in America. AMF-produced Harleys began rolling off the York Pennsylvania assembly line, although the AMF logo had been appearing on gas tanks since 1971. Harley-Davidson was now just one of dozens of divisions in a corporation, and quality control was becoming an issue.
1974 Sportster
Under the control of AMF, build-quality seemed secondary. To increase profits, the corporation began streamlining production and cutting the workforce. This led to a 101-day strike by union workers. With the influx of quicker and cheaper Japanese bikes, Harley-Davidson's share of the 750cc and larger motorcycle market had fallen to 21 percent.
1975 Sportster
New federal regulations required all motorcycles sold in America to have left-side shift and right-side brake controls. AMF's remedy was to continue using the existing engine cases and route the gear-shift linkage across the back of the engine, thus avoiding the expense of re-tooling. Riders endured soggy shifting for two years, until new cases were finally fitted in 1977. Approximately 5,300 Sportsters were produced in 1975.
1976 Sportster
To help celebrate America's 200th Birthday, Harley-Davidson offered special Bicentennial Edition models, with commemorative decals applied to the gas and oil tanks. Sportster models would switch from Bendix to Keihin carburetors later in the year.
1977 Sportster
In an effort to re-capture some of its lost market, two new Sportster models were offered in 1977. The XLT was set up in touring style, with a thicker seat, touring handlebars, saddlebags, and windshield. It was also geared higher, and carried a larger 3.5 gallon tank. The other new model was the XLCR.
XLCR Cafe Racer
The limited edition XLCR Cafe Racer sported low handlebars, rear-set foot pegs, and came in black only. A new frame, designed for better handling and more lean angle, featured extended rear frame rails, with the rear shocks positioned more vertically. Wheelbase measured 58.5 inches. The engine was finished in wrinkle-black engine paint with black siamesed exhaust pipes.
Dual-disc front brakes and cast aluminum wheels, optional on other models this year, were standard. The rear brake was a single disc.
A front bikini fairing, four gallon gas tank, and fiberglass tail section helped the bike achieve a sporty look, and are unique to this model.
XLCR models used a solid-state voltage regulator, and also had more radical valve timing than the other Sportster models. Top speed on the 480-pound bike was around 110-mph. Now prized collectors items, XLCR's sold poorly when new, with less than 3,200 built in the two years produced.
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