What Is Motorcycle Handling?

Admin · October 19, 2023

Kevin Cameron has been writing about motorcycles for nearly 50 years, first for Cycle magazine and, since 1992, for Cycle World. (Robert Martin/)

Reader Joe Broussard often writes to CW with comments. Today his subject is motorcycle handling, going back to the time when European off-road bikes were said to “have it” and Japanese bikes, while fast in a straight line and mechanically reliable, did not.

In that era, Japanese engineers were not even clear on what Western critics were talking about with this word “handling.” The US mass market had shown that quarter-mile time and top speed were the only performance variables of any market value. That was fortunate, for they were easily measured with readily available equipment.

Cook Neilson was the man who raised Cycle magazine from a remnant of the Floyd Clymer era to being a widely read and respected actual information source. He made a point of trying to understand why Japanese motorcycles—on or off-road—so often handled strangely.

Let’s begin with a purely operational definition of motorcycle handling. Handling is the set of vehicular qualities that results from actively correcting the problems pointed out by riders.

In the time of which Mr. Broussard writes, European makers such as Bultaco, Maico, and Jawa had been involved for years in off-road sport, working hard to improve the performance of their bikes in competition. Japanese manufacturers became aware that this activity could be a profitable market, and began to build their own off-road bikes, such as Yamaha’s 250 DT-1. Because the Japanese industry had not yet recovered from the simple approach of quarter-mile-time-and-top-speed, they had come only a short way along the process that leads to “good handling.” The Japanese product looked OK but had not yet had the benefit of the R&D the Europeans had already done.

Yamaha’s DT-1 was a first step to good-handling Japanese motorcycles. Cycle World

Remember also that the Japanese industry had from early days offered models with the word “scrambler” in their names, but in most cases these were just high-pipe versions of streetbikes having no off-road capability at all. Yamaha’s Ascot Scrambler was actually given a tuned-up YDS-2 250 twin engine but its only real utility off-road was as a flat-tracker.

Off-road handling had to wait until Edison Dye brought European MX riders to the US, allowing everyone to see that there was something about European bikes (and riders) that would have to be learned by any newly involved manufacturer before improved results would come.

The same was also happening with streetbikes. Honda designed and built the 750 Interceptor as a 1983 homologation special to make its second-generation sportbike legal for US Superbike. It was stunned when the new bike sold out, leaving a large number of riders waving cash and asking when they could expect their Interceptors. What was different? The extensive reengineering necessary to make 1970s first-gen Kawasaki Z1s and Suzuki GSs raceable had been designed into the Interceptor from the beginning.

Honda’s 750 Interceptor was built as a homologation special and was snapped up in a flash. (Cycle World/)

What drove this change? Japanese makers saw that competition success sold bikes, so they got busy trying to win races with existing designs. Those first-gen Superbikes were combinations of whippy 1960s chassis, short-travel suspension, and narrow, hard tires joined with engines making three times the power of a 1965 Triumph Bonneville. They handled badly! I watched those early Supers rounding the old Riverside, California, Carousel at the 1977 AMA national there and every single one was oscillating in weave.

The differences were magnified at Daytona’s elevated speeds. While the European bikes (Ducatis, Guzzis, and BMWs) were able to reach their top speeds without serious instability, riders on Japanese big-inchers were unable to use their much greater power because they became frighteningly unstable long before reaching top speed. For a time, and in the absence of a better theory, European Superbikes were vaguely believed to have some kind of “European flair”—an indefinable “essence” that made them superior.

Of course, the real reason for this difference was not berets or flowing silk scarves. The Europeans had done a fair amount of development work on their big bikes and the Japanese had not.

Meanwhile, Yamaha and Suzuki jumped into European 500cc GP roadracing and quickly discovered that handling was a real thing that could be achieved by a serious dialog between riders and engineers. Essential to this process were practical and experienced trackside people like Kel Carruthers. Kel, for one, showed Yamaha engineers that when a bike’s steering was heavy and slow, a person of experience could just saw the goddamned steering head off and weld it back on at a different angle. And the rider’s lap time would shorten. Handling was as real as quarter-mile time and top speed, but the only instrument capable of measuring it was the rider.

Herein lies a tale. Neilson and the late Phil Schilling had built their famous modified Ducati known as “The California Hot Rod,” and Neilson had ridden it to victory in the 1977 Daytona Supers race. It was of the era when Euro-bikes were admired for “cornering as if on rails” and experienced riders noted that you had to choose your trajectory with care because you wouldn’t be able to correct it once committed to a corner. Despite the fact that locomotives actually are on rails and cannot be steered at all, this was a much-admired quality.

Then Neilson was invited to Japan by Suzuki to ride its RG500 GP roadracer. When he returned from that trip he was a changed man. He blurted out, “When you’re in a corner and you’d like to be over there, the bike seems to just go there without any action on your part!” That RG had been the result of dialog between engineers and riders.

Barry Sheene on Suzuki’s XR14, which became the RG500. Gold and Goose

Suddenly it was clear that handling was not some hoary magic, handed up out of a lake like the sword Excalibur. It was the result of a series of plain old physical experiments aimed at discovering ways to make motorcycles respond promptly and precisely to rider inputs. Riders were moved forward on bikes. Steering rake was progressively reduced from the 31 degrees of the sacred bevel-drive Ducati to the 27 degrees of Yamaha’s RD350 and Kawasaki’s Z1, and later, to the approximately 24-1/2 degrees of the present day.

It was also discovered that the accepted practice of pushing the engine back against the rear tire let rivals get the jump on you out of corners because their bikes, with engines mounted farther forward, were not out of control from pawing the air. They were accelerating. Accordingly, Suzuki kept moving its engines forward until riders said “Enough!” (which in some cases was not until the radiator had been slotted to allow an even more pronounced forward position).

There was a revolution in suspension units. When Kenny Roberts complained that harsh compression damping on a Yamaha factory monoshock was making his bike “step out” in unsmooth corners, the response was puzzled looks.

So he said, “Can you build me a shock with no compression valve at all in it? Again, much tooth-sucking but no action. So he insisted.

Yes, they finally admitted, they could build such a shock. When it was installed and Kenny resumed testing, his lap times dropped. He had proved that no compression valve at all was better than the existing hardware—the engineers had seen it with their own eyes. Soon it was realized that compression damping orifices—even when wide open—were at that time so small that compression damping became essentially infinite when a bump drove the suspension unit at a high shaft speed.

This is the essential meaning of handling: Riders and engineers accumulating knowledge in solving problems that stand between them and better performance.

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