How one bad bike took Bimota to the brink
Unless you’re big into motorcycles, chances are you’ve never heard of Bimota. That’s because Bimota is a small and enigmatic Italian manufacturer, best known known for its two decades of building bike frames. And when Bimota had the ambitious idea to engineer its own street bike engine, it looked like the revolutionary project would take the company to the next level. Instead it drove Bimota to its ultimate and eventual failure.
Bimota got its start building sport bike frames for existing engines from Honda, Suzuki, and Kawasaki. Founded in 1973 by the trio of Valerio Bianchi, Giuseppe Morri, and Massimo Tamburini, the company name is a portmanteau of their names.
In 1972, Tamburini was racing his Honda 750-cc bike at Misano Circuit when he crashed, destroying the bike and cracking three ribs. While in recovery, he designed and engineered a new frame with a lower center of gravity, and lower weight, that was still strong enough to handle the Honda motor’s big power.
By the 1980s the company had developed something of a name in the world of motorcycle racing, and in 1985 the company was almost exclusively using Ducati-sourced powertrains for its street bikes. Tamburini had been an engineer with Ducati before starting Bimota, and the two brands were a natural fit.
After 20 years of designing and building frames, Bimota got the itch to make its own engines. A process that is lengthy and expensive, without a doubt. To make things more difficult, Bimota wanted to build a revolutionary engine that had never really been tried before; a fuel injected two-stroke twin displacing 500-cc.
Enter the V-Due 500
A fuel-injected two-stroke had never really been attempted before, but with emissions laws in Europe and the U.S. getting ever stricter, large bore two-stroke sport bikes were a disappearing breed. Because a two-stroke engine has its intake and exhaust cycle on the same stroke, there is no way to prevent unburned air/fuel mixture from escaping right out the cylinder with the exhaust as it leaves. Unburned fuel in the exhaust is always a recipe for high tailpipe emissions.
In order to prevent unburned fuel in the exhaust gasses, Bimota developed a precisely timed direct-injection fueling system that pulsed fuel into the combustion chamber only after the piston had slid past the exhaust port, sealing the fuel inside and cleaning up the engine’s tailpipe numbers.
The major advantage to a two-stroke cycle is a simpler, lighter-weight design that is more powerful than a four-stroke motor of similar displacement. In some cases a two-stroke will produce as much power as a four-stroke with twice the displacement, thus a 500-cc two-stroke engine might have peak power similar to a 1000-cc four-stroke. It also meant that once Bimota finished the so-called V-Due 500, it was a new tech marvel that was especially lithe but packed gobs of power.
Bimota whipped up a pre-production prototype for the international motorbike press to review. With a prototype engine that had been carefully assembled by the original engineers and incredibly accurate high-flow fuel injectors developed by Ferrari, the bike was an instant hit among the critics. The bike, as per usual Bimota standards, had an incredible chassis that weighed just 320 pounds dry. The engine was powerful and an absolute riot to wring out. The bike was sexy, too. It incorporated liberal use of carbon fiber. The V-Due was a proper Grand Prix bike for the street.
The engine had been in development for eight years, and the chassis was a culmination of the everything Bimota learned over the years. Nobody was as eager to hear accolades than Bimota itself. It had bet the company’s life on this bike being a success, and they’d gotten it right… Until they didn’t.
Things head south
In the process of getting the bike ready for production, Bimota found out the small-orifice Ferrari-sourced injectors were not available in the numbers the company needed. The company could not find a manufacturer which offered a similar fuel injector with the same precise metering the two-stroke twin required.
A further problem, which wasn’t discovered until much later, involved the crankshaft seals. The seal used on production V-Dues was not the same strength as the one in the pre-production bikes, and would often develop an inconsistent leak.
Customers told Bimota that they were absolutely in love with their bikes when they worked, but with inconsistent fueling and inconsistent compression, they didn’t work more often than they did. The bike ran erratically and was deemed by many riders to be the absolute opposite of smooth and reliable. The roll out of the first all-Bimota bike did not go smoothly, and the initial run of 150 bikes had to be recalled in 1999 to salvage the brand’s integrity.
During the recall period, Bimota wanted to raise awareness that the issues V-Due owners faced were being fixed. In kind, they built a 26-bike run of V-Due Corsa motorcycles for an Italian national one-make Clienti racing series. Not needing to conform to street rules, the race bikes used a pair of Dellorto carburetors. Sadly, the bikes were still inconsistent and difficult to ride, thanks to the crank seal problem. In an effort to fix that particular problem, Bimota machined the crankshaft to fit a larger and more robust seal, but then the crankshafts themselves started to fail in spectacular fashion. The outlook was bleak.
Bad to worse
Just when the company was at its lowest, disaster struck again. The Bimota team had been running a respectable mid-pack World Superbike race team effort for the 2000 season. During a freak downpour of rain at the Phillip Island round in Australia, rider Anthony Gobert had even racked up an early season victory. The team had brokered a deal with Levi’s denim to sponsor the effort, but six race weekends into the 13-weekend series the jeans maker withdrew, leaving the team holding the bag on millions in bills.
With its only motorcycle the subject of a massive recall and a race team with no sponsors, Bimota was forced into receivership in 2000. If it had to solely weather either the V-Due failures or the WSBK sponsor withdrawal, the company might have survived. But both concurrently was too big a burden to bear. The company’s new owners set about a revival plan immediately, and began by selling the V-Due 500 project off to fund the effort.
New lease on life
An entrepreneurial fellow named Piero Caronni took on the project of making the V-Due the bike it had promise to be. He purchased all of the recalled bikes, parts, patents, bucks, molds, and documents in one fell swoop and set about making them work. As a smaller manufacturer, Caronni presumably did not need to meet the emissions specs that Bimota had, and therefore ditched the complicated fuel injection for carburetors.
Caronni studied the crankshaft seal problems and decided the easiest way to solve this issue would be to cast brand new engine cases with enough space to expand the seal’s outer diameter rather than cut into the crankshaft to accommodate the stronger seal. By all accounts, Caronni’s fix worked. The V-Due was suddenly the bike it was meant to be all along.
Between 2001 and 2003, Caronni refitted all of the recalled bikes to V-Due Corsa Evoluzione specification. In total, 120 bikes have been retrofitted with the new case and carburetors, among other bits. In 2003 the V-Due Evoluzione was crafted with 14 examples built featuring as much as 120 horsepower. By 2005, Caronni had developed another version of the engine with 130 horsepower on tap for a V-Due Edizione Finale, of which 30 were produced. There are occasionally found some original non-Caronni-fixed V-Due 500s out there in the world, even a few still in the original crate.
Bimota still exists, but it is hardly the same company as it was before the V-Due. The highly advanced superbike was an ambitious project, and proved to be its downfall. Where a traditional four-stroke 1000 might have succeeded for the company, it chose to go the path untraveled. For that, it still deserves all of the accolades. Why go with the flow when you have an opportunity to make something completely unique? If it had been right from the beginning, Bimota might still be lauded as heroes for the effort.