Someday they were bound to build it-a rugged machine of modest proportions, without a cantankerous bone in its body, capable of virtually effortless and unlimited cruising speed in full road dress. We saw it coming two years ago when we covered BSA's unit-construction 40-inch twin in "peasant model" form ("Royal Star," Nov. '62 HRM) and read 105-110 mph on the dial time and again without so much as dusting off a spark plug. Our comment at the time was to the effect that this engine would be the basis of a really hot one to come-and come it did!
Relatively few but important modifications during the intervening time turned an already potent powerplant into a real scorcher. Dubbed the "Lightning Rocket" in its new 56-horsepower version, the engine's induction capacity was increased with the addition of dual 1-1/8-inch-venturi Amal Monobloc carbs, bigger valves, stronger springs, full-race cam, and domed 9:1 pistons. A measure of the Lightning's success is most forcefully drawn from the following statement: Running full standard equipment, including mufflers, air cleaners, and electrical system, the Lightning indicated the highest speed of any motorcycle tested to date by HRM!
After several weeks of dodging city traffic, checking mileage, maneuverability, brakes, starting, and so on, our curiosity as to its top-speed potential could no longer be put off. The ease with which it pulled its high 4.53:1 overall gearing off the mark in town warned that the test site should be long, smooth, and unobstructed; Bonneville seemed about right, but El Mirage Dry Lake was conveniently closer. Thirty minutes spent cruising the lake bed showed an acceptably smooth section about 2 miles long, with more overrun if needed. After studying landmark guides at each end to sight on, the Lightning was pulled back for the first strike, running with a slight tail wind. A few seconds later I almost swallowed my gum; the speedo needle had run off the scale, and the tach was hovering just under seven grand. Speedometer calibrations on this new rubber-mounted instrument are carried to 125, and the needle had stopped considerably beyond, indicating 130 mph! Without so much as stopping, the bike was wheeled around and brought back into the wind, registering 118 mph. In the 10 or 12 runs that followed in rapid succession, various readings were taken between 120 and 130 mph. Finally, the Lightning was brought in for inspection and layover for a dead-calm air condition. Neither sight nor sound gave hint that the machine had been pressed to the limit; tick-over at idle was as steady as ever before, and neither oil loss nor loosening was evident. There was only one giveaway: Air pressure had caused the headlight to take a bow.
Then it came-dead calm-and the Lightning was hurriedly fired for two more runs, one in each direction, to verify its speed without wind interference. The first shot made sense-125 mph with a 6,500-rpm tach reading. The second made even more, with identical speed and rpm figures. How honest was it? We were curious, too, so a week later the speedometer was removed and checked at a testing laboratory for accuracy. The report showed a 2-percent error (optimistic) at 100 mph, which, if an issue were made of it, could be discounted as compensation for the slight amount of slippage incurred on the dusty surface as compared to the better grip one would find on a hard, paved road. The tach, incidentally, was found to be off considerably more; it should have been reading 7,300 at 125 mph instead of the 6,800 indicated. Gearing on the machine was as follows: 28-tooth engine sprocket, 58-tooth clutch, 21-tooth countershaft, 46-tooth rear wheel. Lightning models built subsequently may have slightly different gearing (ours was actually a fraction lower than the brochure stipulates), but this is strictly a matter of personal choice.
Since we went into considerable mechanical detail in the '62 HRM report, let's just review the technical aspects of the Lightning, which, except for the engine modifications already mentioned, are pretty much the same in all other aspects. Briefly, the engine is of the popular vertical-twin configuration with over-square bore and stroke at 75x74mm, respectively. One of the many exceptional features of this overhead-valve "hemi" is its total lack of exterior oil lines and pushrod housings between crankcase and head. All such passages are cast into the deeply spigotted iron barrel, which means there are only two sealing joints between the crankcase and head-reduced chance of oil seepage and smoother exterior appearance. Another benefit of the compactly integrated design is its ability to dampen mechanical noises inherent in an air-cooled engine to greater degree. Inside refinements include a single camshaft for reduced cam-drive friction; double-gear oil pump; double-coil racing valvesprings; dual coil; and dual-point battery ignition with alternator. Two cleanable oil filters (crankcase sump and oil tank), along with a crankshaft sludge trap, ensure safe lubrication. The four-speed gearset, though housed in the crankcase casting proper, is separately contained, with its own oil supply. Translated into performance, these features gave an extremely efficient account of themselves: The engine breathes exceptionally well, is not the least bit temperamental as one might expect from a runner of this caliber, and gave every indication of being most durable (this is one of the rare instances where our test bike had been flogged by every press rep in Southern California before we made the scene). Nothing daunted its enthusiasm.
Obviously a powerplant with this kind of performance will seldom be "put to the wall" in its lifetime and therefore would make an ideal touring machine for the rider impatient to cover lots of ground in a hurry without the slightest fuss. Because the Lightning isn't even breathing hard at 70-80 mph, it would make an ideal tourer (I wouldn't recommend a better one), and its extra-long saddle-to-bar relationship permits two people aboard without the slightest crowding. Although we didn't try, I'm sure that the bike would stand for the fitting of generous saddlebags and windshield without appreciable loss of performance (you've got 30 mph to play with at least), and would still deliver excellent economy (test results showed 48 miles per gallon in stop-and-go traffic!). Even with its sporty 3-gallon gas tank, the bare Lightning should crowd 150 miles between stops at legal road speeds.
In the caustic-comment department there's little of real consequence, but we do have a couple of bones to pick. I would like to see future models benefit from more attention to wiring details in the rear fender area. Since the wires to the taillight are not carried in a loom, the first moderate bump with two people aboard (rear shocks set on soft) caused the rear wheel to rebound far enough to grab the wires, tear them out, and short them out against the fender. If future shipments from Birmingham are not improved (we're told they are considering the situation), the problem can be rectified by the private owner by slipping a plastic or woven hemp sheath over the wires and securing this with clips along the inner edge of the fender, out of reach of the wheel. Another point of concern involved the throttle action; admittedly, pulling two throttle slides at once involves double effort, but throttle action in this instance was felt to be unduly stiff, even sticky when moving the control right off idle position. In all other respects the Lightning was mechanically perfect, and its workmanship and materials of the highest quality; no failures or deterioration were experienced.
Maneuverability and stability, extra- important in a vehicle capable of the reported speeds, were both first-rate. One of the points brought out back in our '62 test was that the front suspension was overly soft and susceptible to bottoming heavily and often; we are glad to report that the machine just tested was not so afflicted, apparently having been cured with the fitting of stiffer springs. Ride and firmness are much improved, and no bottoming was noticed at either end once the rear shocks were properly set (three-way adjustment here). Who says road tests aren't taken seriously?
With a name like Lightning, it's pretty clear what kind of an image the manufacturers were trying to create. If it had four wheels, you can bet it would have GT or GTO tacked onto the title-definitely in the super sport class. This one's for real, with such subtle refinements as Dunlop Gold Seal K70 high-hysteresis tires (super-cling, especially in wet weather) of 3.25, 3.50x19 front and rear; single-bolt, splined, quick-detachable rear wheel (a real rarity these days); chromed-steel sport fenders; sport gas tank; rubbermounted 8,000-rpm tach and speedometer; high-efficiency mufflers; 8-inch front brake; steering damper; and rubber fork boots. Appearance-wise, every effort has been made to make the Lightning as attractive as it is fast; chrome is in the near-custom category, including the chain guard and upper fork covers, while all aluminum parts have been thoroughly buffed. Although the oversize headlight is out of character, befitting the otherwise sporting theme, it may have been intentional to give the customizers a way out.
If you are competition-minded, you can get the same gutsy engine in an abbreviated racing chassis with upswept straight pipes, special bars, gearing, heavy-duty suspension and tires, sans lights but capable of sporting some if you care to rig a direct lighting setup to the included alternator.
As for price, the Lightning Rocket tested is $1,198 plus setup and freight. Although we didn't weigh this according to our usual custom, it has to be within a couple pounds of the single-carb job which we did weigh at 425 pounds fully gassed.
It's pretty sophisticated machinery for the money, and after that El Mirage bit, I'm not too sure that our first hunch-to head for Bonneville-wasn't right after all. One-twenty-five with all the bric-a-brac bolted on is a darned good place to begin stripping and tuning. Who knows-we might have been operating a record machine without a sanction!