1983 Harley-Davidson XR1000

Inspired by Harley-Davidson's iconic dirt track racer, the XR750, the XR1000 debuted in 1983 as the original "street tracker" and looked as if it should be power sliding around a mile dirt track. Based heavily on the XLX Sportster chassis, the XR1000 featured iron cylinders reduced by ½" and fitted with Jerry Branch aluminum SR style heads. Like the race bike, the XR1000 wore a pair of 36mm Dellorto carburetors on the right side of the motorcycle while distinctively paired dirt track style exhausts swept high on the left side. With lightweight aluminum pushrods and 9:1 compression XR pistons, the motorcycle was rated at 71 horsepower at 5,600 rpm and would propel its 490 lb. dry weight to 115 mph. It sold for $6,995, and 1,018 units were produced.


The 1984 Harley-Davidson XR1000 represents the last of the breed, as the Motor Company was preparing to introduce the new Evolution engine Sportster series, the old iron barrel Shovelhead motor was destined for the history books. It is finished in the optional scheme of Harley-Davidson's factory racing black and orange, with red line rims and improved twin disc brakes up front. Only 759 XR1000's were produced in 1984.


XR History


Back in the early 1980s, Harley-Davidson executives were still a bit nervous about the viability of the company. After all, they were trying to sell old-fashioned pushrod, two-valve, air-cooled V-twin machines in an era of multis with double overhead camshafts, 4-valve heads, and liquid cooling.


Shortly after Harley bought itself back from AMF in 1981, the decision was made to junk the revolutionary Nova prototype AMF had been developing, which had a V-four engine incorporating all those contemporary innovations. However, something decidedly kick-ass was needed to convince the faithful that this 80-year-old company still had what it takes to whoop the upstarts, and it needed to be done on the cheap.


Harley’s answer was to get to work on an engine that was first sold to the public in 1952--the 45-degree, 45 ci, unit-construction K-model. That K was a 750 cc flathead, later upped to the 883 KH, and then revamped to the overhead XL for 1957, with an 883 cc XLR version for the racing crowd.


Creation of the XR1000

A change in the AMA's racing rules led Harley to build the iron-barreled XR750, a de-stroked XLR, which debuted in 1969. Though it wasn’t very successful, it was the beginning of a legend, as it was followed by the alloy XR750 in 1972, which did become a tremendously successful, dominating racing for a decade.


The new model was going to be an entirely different proposition, with a 1000 cc engine using a combination of XLX Sportster and modified XR750 parts. The end result would become the Harley-Davidson XR1000 and in theory, it sounded easy and inexpensive.


Choosing the pieces


Dick O’Brien, famed head of H-D’s racing department, led the project. A stock Sportster bottom end was used, using special barrels and heads.The engine was bolted into the new XLX chassis introduced for 1982, whose welded steel tubes gave it a more sophisticated look and feel than the old version, which had been made using individual castings. Harley’s engineers had figured out how to balance too stiff with too flexible, creating a frame that had the possibility of handling quite well, assuming the proper suspension components were used.


However, life wasn’t that simple, and problems with the XR’s development immediately began to arise. The XR750 alloy cylinders would not do, as they were too small (750 cc) and even if enlarged they would not fit the XLX cases. New iron cylinders with an 81 mm bore were made, and new aluminum pistons required new connecting rods. The V-twin’s fork-and-blade connecting rods (one rod rides inside the other on the crankshaft), bolted onto the single-throw crankshaft, remained the same, as did the four rather low-lift “Q” camshafts under the right side cover, providing a broad and smooth torque curve.


One advantage was that the new cylinders were designed to use through-bolts rather than the standard Sportster design, which had separate bolts holding the cylinders to the cases and then the heads to the cylinders. There was more finning to aid heat dissipation.


Head work


Complicating things further, the XR750 heads had to be recast for the XR1000. The new heads used slightly larger valves to allow for the increased 998 cc displacement, and also offered better support for the valve guides, considering that this was intended to be a high-mile street bike, not a constantly rebuilt race bike. After basic machining in Milwaukee, the heads were all sent to flow-guru Jerry Branch’s shop in California. Branch did the porting and polishing, shimmed the double valve springs, and put in titanium collars and keepers. None of this was cheap.


One big difference between the iron XL and alloy XR heads was that the valves were set at an angle of 90 degrees on the stock Sportster versus 68 degrees on the XR. This allowed for a shallower combustion chamber and a flatter-topped piston on the XR.


High-test gasoline went in through a pair of 36 mm Dellorto pumper carbs, which both hung out on the right side of the engine wearing large K&N air filters. On the left side of the engine, matching header pipes ran forward, then curved sharply back and over the top of the primary case before concluding in a pair of well-baffled megaphones.


Performance package


Harley claimed 70.6 hp at 5,600 rpm, along with 48 lb/ft of torque at 4,400 rpm. That power traveled along a triplex primary chain to a multiplate wet clutch, through a 4-speed Sportster transmission and out to the back wheel on a 530 chain.


The chassis was, unfortunately, a trifle Sportsterish. With the engine securely bolted in place, the unbalanced 45-degree V-twin transmitted a good deal of vibration to the rider. The Showa 35 mm front forks had a lengthy travel of 6.7 inches and no adjustment. The rake was 29 degrees, with 4.5 inches of trail, and a wheelbase of 60 inches. At the back, a pair of Showa shocks offered 3.25 inches of wheel travel, with preload adjustability.


The nine-spoke cast wheels wore Dunlop Sport Elites; a 100/90 x 19-inch on the front and a 130/90 x 16-inch on the back. Front brakes were good, with a pair of 11.5 in rotors (the first production Harley to wear dual discs) squeezed by single-action calipers. The rear wheel wore the same disc with a double-action caliper.


With 2.2 gal of premium gas in the tank, the XR1000 weighed just more than 500 pounds. In case an XR1000 owner wanted to go racing, Harley also advertised a hop-up kit with 10.5:1 pistons, hotter cams and an unmuffled exhaust system that claimed to offer an extra 20 horsepower.


Racing pedigree


An XR1000 prototype was on the road in the fall of 1982, and being tested at Daytona, when somebody saw a racing potential in the Battle of the Twins (BOTT) class. It may have even been pre-planned all along. One way or another, Dick O’Brien took the notion to heart and set about building a race version nicknamed Lucifer’s Hammer, which was truly exotic. It ran a 10.5:1 compression ratio and put out more than 100 horses at the rear wheel at 7,000 rpm. It used a four-speed transmission, and the drive train was bolted into an old XR750 double-cradle frame, with Italian wheels, forks and brakes. Gene Church rode it to victory at the Daytona BOTT in 1983, which perfectly coincided with the release of the XR1000 and made for great publicity.


Lucifer’s victory set the stage, and H-D dealers hoped to be flooded with calls for this new hot rod. The XR was a great-looking bike; all muscle with a tiny tank, minimal fenders and nothing covered up with flimsy plastic panels.


The good and the bad


New owners found starting their XR1000 easy, with a nice little button on the handlebar. It had a strong engine and would turn in quarter-miles in the 12s with a speed of more than 100 mph. The 998 cc mill gave power from practically anywhere you wanted it: with huge gobs of poke from 2000 rpm upwards the XR would actually pull cleanly away from as low as 1500 revs in top gear. The noise was wonderful, and not at all like a Sportster. But the price to be paid was in vibration, and revving it up to 5,000 rpm was enough to shake your fillings loose.


Another inhibitor for the enthusiastic rider was the small supply of gas, as the 2.2 gallons could run out in 80 or so miles; the 3.3-gallon optional tank was a very sensible choice. The riding position was tough, with the carbs and cleaners sticking out on one side, exhaust headers burning through your blue jeans on the other. The Sportster peg-positioning was a bit too far forward. Rearsets would have been nice, but would have compounded the air cleaner and exhaust problems.


Then there was the matter of the suspension. If you wanted to ride the XR on smooth roads at not-too-unreasonable speeds, everything was fine. But for serious work, the forks and shocks were just too soft, and the shocks didn’t offer enough travel.


There was also the XR’s peculiar desire to turn left. The exhaust system on the left weighted the bike to the left, and the bike consequently enjoyed going that direction more than going right, even on a straight road. It was nothing that couldn’t be managed, but it was an annoyance, nevertheless.


Dollars and sense


The XR1000’s steep price turned out to be a major drawback. Harley had hoped to build this bike on the cheap. Yet with all the unexpected mods that had to be made, the MSRP ended up just shy of $7,000. The main problem was that the XLX Sportster went for $4,000 and it looked a lot like the XR. To add to the XR’s misfortune, for its 1983 introduction the company color stylist had it painted in nondescript gray. The second year Harley had the good, if too late, sense to give it their traditional orange and black racing colors.


Harley turned out approximately 1,000 XR1000 models in 1983, and did not sell them all, whereas 5,000 XLX models rolled off the showroom floors. Approximately 700 XR1000s were built in 1984, but most were sold at discounted prices later on, and the model was discontinued.


Specifications


Make / Model:  Harley Davidson XR1000
Year:  1983(4)
Price New:  $6995
Engine:  Air-cooled, four-stroke, 45o V-Twin, OHV, 2 valves per cylinder
Capacity:  998 cc (60.84 ci)
Bore X Stroke:  81 x 96.8 mm (3.2 x 3.8 in)
Compression Ratio:  9.0:1
Induction:  2 x 36 mm Dellorto carburetors
Ignition / Starting:  Electronic / electric
Clutch:  Multiplate, dry
Max Power:  70.6 hp (52.6 kW) @ 5600 rpm
Max Torque:  48 lb/ft @ 4400 rpm
Transmission / Drive:  4 speed / chain
Front Suspension:  Telescopic forks, 175 mm wheel travel
Rear Suspension:  Swingarm, dual shocks, 100 mm wheel travel
Front Brakes:  Dual 290 mm discs
Rear Brakes:  Single 290 mm disc
Front Tire:  100/90-V19
Rear Tire:  130/90-V16
Seat Height:  29 in (736 mm)
Wet Weight:  487 lb (211 kg)
Fuel Capacity:  2.51 gal. (9.50 l)
Fuel Consumption:  46 mpg
¼ Mile:  12.8 sec. / 101 mph
Top Speed:  115 mph (186 km/hr)


Adapted from several internet websites.