MotoGP 800 - Art & Science

A closer look at the new 800s

With the new era of 800cc MotoGP well underway, our spies in the paddock have managed to snap some pictures of the new bikes. Here is a sampling from the first few races of '07.

The Ducati Desmosedicis have shown incredible straight-line speed, and Australian Casey Stoner used that to his advantage to win three of the first six races. At Mugello, one of the fastest circuits on the calendar, the four Ducatis (Stoner and Loris Capirossi on the factory entries, Alex Barros and Alex Hoffman on the Pramac d'Antin bikes) were fastest, with Stoner reaching 201 mph, just 7 mph shy of the fastest speed carded at the same track in '06 by a 990cc machine. The frame consists of short tubes running from the steering head to each cylinder bank of the V4 engine and a large carbon-fiber subframe mounting to the swingarm pivot (that mounts to the crankcases) and the rear of the engine.

The '07 Yamaha M1's engine and frame layout are very similar to the '06 990cc version's, although the motor appears significantly more compact front to back. Interesting bits include loads of electronics with quick-release connectors, CNC-machined crankcases, O2 sensors in each exhaust pipe and the engine mounts at the front of the crankcase and rear of the cylinder block.

Nicky Hayden's Honda RC212V sported Unit Pro-Link rear suspension at the opening Sepang tests (left), but by the fourth round, in Shanghai, China, a standard rear setup with the top of the shock mounting to a frame cross-member was being used (above). The bulk of the fuel is carried under the seat, opening up the airbox area and putting the heavy fuel nearer to the overall center of gravity, reducing the effect on handling as fuel is used over race distance. Note the carbon shroud over the rear exhaust pipes as they arc over the cross-member, as well as the rubber thrown onto the inside of the swingarm.

Another view of the Honda RC212V. Of all the 800cc MotoGP bikes, the four-cylinder Honda is the most changed from its 990cc predecessor, the five-cylinder RC211V in this case.

New tire rules for this year limit Bridgestone and Michelin to 31 tires for each rider at each race, chosen before the event. The Michelin runners struggled at the first few tracks, where no testing had taken place, unable to make tires to order the day before the race as had been the previous practice. A clause in the ruling allows an unrestricted number of tires for Dunlop riders on the Yamaha Tech 3 team.

The Kawasaki ZX-RR's rear shock has a linear transducer for data acquisition attached. A threaded insert in the frame allows ride-height adjustment, as opposed to an adjuster on the shock itself or an adjustable-length rod on the linkage.

This Brembo caliper on the Ducati Desmosedici is a work of art: Machined from solid billet, the caliper houses four radially ventilated pistons and two carbon-fiber pads.

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