For the past 30 years there’s been a love-hate relationship between motorcycle designers and carbon fiber, but the latest pearls from BMW and Ducati show the prejudices preventing its structural use in road going motorcycles are finally breaking down.
While carbon has long since been accepted as the ‘price is no object’ material of choice when it comes to cosmetic parts – fairings, exhausts, etc. - it’s had a troubled history when it comes to its use for structural elements like frames and swingarms. Despite attempts being made at carbon-framed racebikes dating back to the ‘80s – Honda made a prototype NR500 racer with a carbon chassis as early as 1983, and Armstrong had a carbon 250 GP bike in 1984 – they’ve never enjoyed the success of bikes made with more traditional materials.
So we won’t see carbon-framed MotoGP bikes in 2017, but there will be two new production models from leading manufacturers using carbon-fiber frames: Ducati’s 1299 Superleggera and BMW’s HP4 Race. And both motorcycles mark a big leap forward for carbon fiber.
The BMW and Ducati are full carbon machines, using the stuff for their frames, swingarms and wheels, as well as the bodywork. Both are exceptionally light and offer incredible power-to-weight ratios. Both will be handmade in tiny numbers and sold to the wealthiest of enthusiasts for eye-watering amounts.
These toe-in-the-water carbon ventures might seem irrelevant to most of us. The Ducati 1299 Superleggera will cost an estimated 4 million THB if not more and the BMW isn’t likely to be a lot cheaper, so why should we pay any attention? Well, because, as with any new technology, it’s likely to eventually filter down to us in the form of models that are much more affordable.
And it’s not just limited to premium European brands – other firms have their eyes on the possibilities. Honda is known to have been working on motocross bikes with self-supporting carbon-fiber seat units, and developing the means to mass-produce such parts. From there it’s only a relatively short step towards making further mainstream carbon machines.
BMW’s patents have also revealed that the firm has ideas for carbon-fiber trellis frames, purely made from straight extrusions of carbon. That suggest it will eventually use the material to replace steel on motorcycles like the R-series boxer models.
Provided the Ducati 1299 Superleggera and BMW HP4 Race are successful in sparking the imagination of riders and creating a desire for more carbon fiber offerings, it seems certain that the future for lightweight motorcycles is in composites rather than metals.
BMWThe Germans official line on the BMW HP4 Race – only shown as a prototype but promised in production form before the end of 2017, is that it’s to be handmade in small numbers. But the company’s own patents have already betrayed its intention to bring carbon-fiber to the masses. More than a year ago we revealed the company’s plans for factory-made carbon-fiber frames, including a beam frame design that looks near-identical to the one on the BMW HP4 Race prototype.
While visually similar to an BMW S1000RR beam frame, it’s internally quite different. There’s a structure of ‘pultruded’ square-section carbon tubes inside each frame rail. Not that BMW’s experience in the area is unparalleled – back in 2003 it developed pioneering techniques to mass-produce carbon fiber structural components for cars. Just as the BMW HP4 Race is a limited-edition, the first car to benefit was the limited edition 2003 BMW M3 CSL, which had a carbon-fiber roof. On the following generation of M3 Coupe, from 2007, the carbon-fiber roof was standard. In 2013 BMW launched the i3, an electric city car with a full carbon-fiber monocoque and a mainstream price tag, and the latest BMW 7 Series luxury cars all use similar technology.
DucatiDucati’s 1299 Superleggera is similarly being produced next year in small numbers, but it wouldn’t be a shock if the Panigale’s replacement – expected in 2018 – features a carbon fiber chassis, at least on higher-spec models. Ever since the Ducati Panigale first appeared with its radical monocoque chassis, a carbon-fiber version has been expected. In fact, the chassis concept’s roots are in the carbon-framed Desmosedici GP9 of 2009, and when the Panigale was shown in November 2011, many expected the higher-end versions to get a carbon monocoque. Now it’s finally happening.
Like BMW, Ducati’s parent firm has plenty of composites experience. The firm also owns Lamborghini, which makes carbon-monocoque road cars, albeit not in the mass-production BMW fashion. Don’t be surprised if all high-end Ducatis comes with carbon-fiber frames in a few years time.
Carbon-Fiber Frames DevelopmentCarbon-fiber frames have been less than successful in motorcycle racing, but that’s not reason to write the idea off when it comes to either road legal motorcycles or future race machines.
The oft-quoted reason for carbon’s lackluster race records is it’s too rigid – it doesn't provide the imperceptible flex of a steel or aluminum chassis, and either leaves riders lacking on-the-limit feel or exacerbates problems like chatter.
Carbon structures can be developed with flex if needed, but it’s a learning process and no manufacturer has stuck with the material long enough to iron out every wrinkle. The real issue is that there’s a minimum weight in MotoGP which eliminates carbon’s main advantage. Road legal motorcycles have no such minimum weight restriction. Ducati is claiming that its 1299 Superleggera is only 165 kilograms, ready to ride (about 154 kilograms without liquids) and the Ducati 1299 Superleggera manages it with a larger engine, lights, mirrors, indicators, a catalytic converter… and everything else what makes it road legal.
Road riders are never likely to reach that last fraction of a percent where they’re relying on flex to feel whether the motorcycle’s losing grip, and even if they are, the latest traction control technology and cornering ABS makes it far less of an issue than it was even in 2011 when Ducati last raced a carbon-fiber-framed GP bike.