The Best Transverse Twin Sportbikes Of Yesterday And Today

If transverse twins were meant to be used in sportbikes, they’d be turned the right way in their frames in the first place. Or maybe not.

Long-time Cycle World columnist Peter Egan astride the BMW R90S.Cycle World

Can you imagine a BMW or Moto Guzzi MotoGP bike sporting a transverse twin engine? Neither can I.

If a modern sportbike’s merit is judged by lap records and race wins, hoping an opposed twin will get there seems as optimistic as using a matchbox derby car to win at Daytona. If pigs were intended to fly, God would have given them wings, right?

Putting a pair of cylinders out in the breeze made a whole lot of sense when flowing air around finned cylinders and valve trains was the only way to keep them cool, but limited cornering clearance (in 180-degree opposed twins) and the longitudinal orientation of the crankshaft, which requires a heavy shaft final drive, preclude ultimate performance. Moto Guzzi and BMW, marques synonymous with transverse layouts, typically wedge them into sport-tourers, cruisers, or ADV bikes where chasing rev limits is less important than reliability and character—to say nothing of tradition.

Although it’s an unlikely configuration for a sportbike, there’s something admirable about pursuing extremes, of pushing a machine’s performance beyond the perceived boundary of its design.

Butler & Smith’s 750 BMW racebike from the early ’70s piloted by Reg Pridmore is the proverbial flying pig. Icarus-like, the team aimed to prove that Beemers weren’t stodgy old-man bikes but could be taken racing. And they could win. The bike was developed far beyond its original form, which made its triumph all the sweeter, forging a unique chapter in the annals of racing lore. Among many modifications, the team shortened the cylinder heads by half an inch to improve cornering clearance. You can imagine other racers looking askance at the bike in the pits: “Say, Reg, it looks your bike’s engine is short a few fins there…” Ah, American superbike racing in the ’70s.

Moto Guzzi MGS-01
Moto Guzzi MGS-01Marc Urbano

Straight from the factory, there are few motorcycles that can push the limits of their design in such dramatic and blatant fashion. Lest our Mandello del Lario friends feel left out, we submit the MGS-01 as exhibit A. It's a 122-hp, 423-pound Guzzi for goodness' sake. There are simpler ways to go fast but few as unconventionally plucky.

More attainable—though less extreme in their quests for performance than a one-off racebike or an exotic bit of Italian unobtanium—our picks for best transverse twin sportbikes remain the motorcycle world’s marching penguins and flying pigs.

Yesterday: BMW R90S

BMW R90SCycle World

When BMW introduced the S1000RR in 2009, it marked its territory like a well-hydrated Rottweiler. It was BMW's first true race replica and it changed some minds about the German brand, just as the R90S had 35 years prior. The R90S was in no way a race replica. Heck, the race-rep category was still a decade away from being born. But never before had a BMW been so fast. Or expensive. At $3,400 the R90S was $1,180 more expensive than a Ducati 750 Sport and $1,435 more than a Kawasaki Z1. In spite of running slower through the quarter-mile—according to the 1974 issue of Cycle in my lap—on the road the R90S could pull away from the Z1 in any gear. Well then.

The R90S was without a doubt a halo bike. It was sporty, comfortable, reliable, and attractive. It was a true GT bike designed for going fast and going far. It was beloved from the start, if not derided for its high price tag. Today, it’s still coveted and competent.

Today: BMW HP2 Sport

BMW HP2 Sport
BMW HP2 SportCycle World

Describing the BMW R1200S as "gonzo" is like a teetotaling granny calling cider gone hard in the fridge "hellfire." The HP2 Sport, on the other hand, does have a tinge of hellfire to it. True, 128 hp and 392 pounds aren't exactly going to light the world on fire, but calling it anything other than a sportbike would be to misjudge it. Underseat exhaust and trick carbon-fiber subframe make it all the more eye-catching.

To the sport motorcycle enthusiast, it’s hardly arcane knowledge that BMW’s racing motorcycles of yore—such as Georg Meier’s 1939 Senior TT winner—were supercharged. If BMW took a page from its own history and supercharged the HP2 engine and made the whole thing look like an R nineT Racer, that would be truly thrilling. Any takers out there?