Pops Yoshimura and the Birth of Muscle


Look, I’m a stick in the mud. Not only that, I’m inconsistent. On one hand, bullets of nervous sweat pop up on my forehead the minute my home Wi-Fi hiccups, on the other I dream of all electronics, rider aids and sophistication being removed from motorcycle racing.

Why? They’ve ruined it. Sure, the best guys still win, but electronics, even the most basic examples, have helped homogenise racing. Now there is barely any variety.

Look at any class and there is a right way and wrong way to do it. Technology has removed the grey areas. No one needs to go with their ‘gut feeling’. And even fewer take risks when it comes to development. In public, at least.

The scientific approach – testing everything behind closed doors, on wind tunnels and with telemetry, has taken romance, repeatedly slammed its head in the garage door and buried it behind the Research and Development department.

Now there is just one approach, one line, one tyre. To spot the differences you need a microscope. And I’m not just talking about the machinery. It’s the riders’ approach too. There are nutritionists, personal trainers – three hours consulting the data while sucking on a bucketful of isotonic slurry. There are teams that even use satellite tracking to determine the optimum apex of any given bend. That’s three satellites to work out the best way around a corner!

To find my race paddock nirvana you need to return to America in the late seventies. For a good example set the time machine specifically for October 1977 at Riverside International Raceway, California. Look for two dudes in Nippondenso leathers hanging around with a crew of oily Japanese fellas.

Steve McLaughlin is one of the racers. Wes Cooley is the other. The leader of the engineers is Pops Yoshimura. A former boy pilot in the Japanese Navy, Pops was fortunate not to become part of the ‘Divine Wind’ ordered to take a one-way flight into an American aircraft carrier during World War II. Lovers of fast Suzukis the world over should be glad he somehow side-stepped the dubious honour of becoming a kamikaze pilot.

Bike-mad and with an understanding of how engines worked and what to do to improve them, Yoshimura arrived in America in the late-1970s and put the cat among the pigeons in AMA Production Superbike racing. And it is those Production Superbikes I love.

Yoshimura worked on both Kawasaki Z1s and Suzuki GS750s and 1000s. Back in 1977 and 1978 the US Superbike road racing scene was on the cusp of hitting the big time. Yoshimura has been described as the founding father of Superbike racing.

‘Back then the superbikes had high handlebars, twin shocks and conduit for a frame,’ remembers Eddie Lawson, ‘But they had a lot of horsepower.’ Science hadn’t caught up with tuning. In fact, science hadn’t even been given a pit pass. It wasn’t until the mid-90s that it would start to make a big impact. Back in the 1970s the cutting edge of pit-lane tech was a new digital stopwatch on a string around your mechanic’s sunburnt neck. The bikes were as dumb as dinosaur droppings.

So while Pops Yoshimura could coerce obscene gobs of power out of an eight-valve, four-cylinder Kawasaki, the bits of the bike he wrapped around the hulking power plant couldn’t handle it.

‘The tyres?’ says Wes Cooley and starts to laugh. ‘Ha, they were really different. Nothing like they’ve got now, that’s for sure. When I started riding the Kawasaki 900 it handled better with street tyres than with slicks. It would hook up too good with the slicks, which would make the frame torque [flex]. I could get away with running road Dunlops and make it slide a lot better. With slicks it would just wobble all over the place. And the brakes? I could put my feet down and probably slow down better.’

What kind of power was Cooley and his competition dealing with? Probably 100-110bhp in 1977 and going on for 130 a few years later (or the same power as 2002 Fireblade).

Lawson really came to the fore in the Superbike class in 1980-81 (before launching into Grands Prix and winning the 500cc title twice), but he first tested Kawasaki’s 1000 in 1979.

‘You look back on it now and you wouldn’t even ride it. At the time you just thought “All right, it’s not actually gonna spit me off, I don’t think. So hold it wide open.” It was pretty crazy. If you could ride that you could ride anything.’

Every top-level bike racer from any era has his own problems to deal with, and it’s indisputable that racing is much closer now that it was then, but I still yearn to see the best of their day bucking and weaving on a glorified, petrified muscle bike. Forget electronic damping and anti-wheelie, in 1977 adjustable suspension was still around the corner.

Wes Cooley knows where I’m coming from. We spoke about those days, when he was one of the most famous racers in America (now he’s an orthopaedic nurse). ‘I think the period is so fondly remembered because it was the beginning of the superbikes… Because it wasn’t all computer-controlled, riders had to ride the bikes differently. It was real life, down to the nitty-gritty, salt-and-rock, blood, sweat and tears. They were rough-looking motorcycles: the high handlebars, the 19-inch wheels and the four exhaust pipes. They weren’t sleek and modern.’

And it is those motorcycles from that raced on circuits across America and beyond, from 1977 to 1981 that still define the term ‘muscle bike’ – they were strong in the arm, thick in the head. They didn’t have electronic brains. They didn’t even have clockwork brains. They were about speed and power, not precision or efficiency. They were of their time. Of course, they were as doomed as they were dim-witted. Progress would see to that, but look at a period photo, of one of the brave riders hanging off, gaffa tape prototype kneesliders licking tracks called Loudon, Daytona and Sears Point or tucking behind number boards to escape the 160mph windblast and try to argue that there are many more evocative sights in bike racing. I dare you. I double-dare you!