Yamaha, which has completed a clean sweep of Riders', Constructors' and Teams' MotoGP World Championships in 2009, gave its annual YZR-M1 technical presentation on Friday night at Valencia (see below for more pictures).

Here are some notes from the presentation, given by Masahiko Nakajima (Fiat Yamaha Team Director and YMC MotoGP Group Leader) and Masao Furusawa (Executive Officer of Motorcycle Engineering Operations):

In response to the new-for-2009 single-tyre rule, reduction in grand prix practice time and engine-change limit (Brno onwards), Yamaha's main aims for the 2009 M1 were to; enhance maximum tyre performance and improve engine reliability, whilst continuing the quest for performance.

Tyre performance was improved by:

o Creating a longer wheelbase motorcycle. This helped acceleration and also created other benefits in terms of aerodynamics (by lowering the rider position) and handling (by moving the rider centre-of-gravity forwards). Top speed was 1% higher in '09 due to improved aerodynamics.

o Optimising chassis rigidity. The 2009 chassis was stiffer in lateral and vertical loading, but more flexible in torsion. This improved braking and cornering.

o A focus on part-throttle engine performance helped Yamaha riders open the throttle 3-5 metres earlier in 2009 than 2008 and produced a 3km/h speed increase at the exit of the final turn at Laguna Seca.

Engine reliability and performance was improved by:

o Optimising the air box design, increasing the fuel pressure, improving the injector position, modifying the piston and combustion chamber design and reducing friction.

o Piston temperature was reduced by 30 degrees without any weight increase and a negligible power loss, doubling the mileage.

o Overall maximum engine power increased by 4% and torque by 3% (comparing Valencia 2008 against Valencia 2009)

A notable improvement in electronics came from relying on gyro (pitch rate) rather than front fork movement for wheelie control.

Yamaha has won ten of the 16 races so far this season. Six of those were by newly crowned seven time MotoGP world champion Valentino Rossi and four by his Fiat Yamaha team-mate Jorge Lorenzo.