Inside Yamaha's 2008 YZR-M1

[tomin40]

Pretty good presentation/article on the development of Rossi's bike from 2007 - 2008.

Interesting on how their first goal was to make the bike work for the tires and that the chassis was made more stiff under vertical and torsion loads but less stiff under lateral.

http://www.crash.net/motorsport/motogp/news/171592-0/inside_yamaha%60s_2008_yzr-m1.html

2007 Review

Rossi only managed four wins and eight podiums during the 2007 season, leaving the Italian third in the riders' world championship - his worst ranking ever in 500cc/MotoGP and lowest title position since his first season of 125cc grand prix racing in 1996.

Rossi was once again the only M1 rider to win a race and Yamaha was only third in the constructors' championship, behind Honda and Ducati. In terms of results it was Yamaha's worst season since 2003, before Rossi arrived.

A review of the 2007 YZR-M1 highlighted the following weaknesses:

1) Lack of engine performance and reliability, specifically:

*Poor acceleration and maximum speed.

*High water and oil temperature.

2) Hard to manage fuel consumption, caused by:

*Poor Air-Fuel ratio on the track.

3) Difficulties in matching the (all Michelin) tyres to the chassis, resulting in:

*Lack of balance between front and rear grip/braking and turning.

YZR-M1 Development Concept

The YZR-M1's development goals were to:

1) Enhance maximum tyre performance.

2) Maximise engine power.

3) Minimise fuel consumption.

This was to be done by:

1) Chassis: Optimise geometry and rigidity

2) Engine: Less friction and better combustion

3) EMS (Engine Management System): Vehicle dynamics oriented

2008 YZR-M1 Developments and Results

Chassis Developments:

1) CLICK HERE to see a diagram showing how Yamaha optimised the M1's basic bike dimensions.

2) CLICK HERE to see a diagram showing how the frame of the YZR-M1 was changed to improve braking and cornering characteristics. The 2008 frame was stiffer until torsion and vertical loads, but less stiff under lateral loading.

3) CLICK HERE to see a diagram showing how the aerodynamics of the YZR-M1 were changed to improve oil and water cooling. This resulted in more consistent engine performance and improved reliability.

Engine Developments:

1) CLICK HERE to see a diagram showing the main engine changes for the 2008 YZR-M1 compared with the 2007 version.

2) CLICK HERE to see a diagram showing the main improvements in engine performance. The pneumatic-valve system (first introduced during 2007) reduced the weight of the valve-system by 40%, lowered the amount of spring force required and allowed for a higher valve lift.

Engine losses due to friction were reduced by optimising the piston and ring, changing the crankshaft diameter, using a new centre oil feed lubrication system and changes to surface treatments.

The above modifications resulted in a 12% increase in maximum power and 8% increase in maximum torque, compared with the 2007 engine.

3) CLICK HERE to see a diagram showing the increase in maximum speed and reduction in fuel consumption, for each track present on both the 2007 and 2008 world championship. The biggest top speed improvement was 16 km/h at Qatar, while the M1 was over 10km/h faster at four other circuits. The biggest drop in fuel consumption was a 13% improvement at Estoril.

EMS Developments:

1) CLICK HERE to see a diagram showing how Yamaha's EMS (Engine Management System) used real time vehicle dynamics to optimise torque delivery.

Summary of 2008 Season

The 2008 YZR-M1 achieved all its racing objectives, winning the riders', constructors' and teams' MotoGP World Championships.

The YZR-M1 took victory in ten out of the 18 rounds - nine wins for Rossi (Bridgestone tyres) and one win for Jorge Lorenzo (Michelin tyres) - and a Yamaha rider finished on the podium at every race. The 2008 YZR-M1 concluded the season with 10 wins, 24 podiums and 7 pole positions.

In brief, Yamaha improved maximum tyre performance due to:

1. Chassis dimensions being modified to suit the tyre.

2. A new EMS [Engine Management System] strategy to maximize tyre performance using vehicle dynamics.

Yamaha's work to maximise engine power and minimise fuel consumption resulted in:

1. Engine performance being improved by 12%.

2. Fuel consumption being improved by 6%.

[Kip Drordy]

Interesting read. I like how they went into the project with goals of more power and better mileage. DuH!!! Who wouldn't want better performance in those two areas? Problem is they tend to be counteractive, more power typically = less mileage. But, obviously they figured it out and made the bike work for them.

BTW those "Click Here" links require registration. But, a good article anyways.

[Dweezel]

Actually, performance and milage are intricately linked via efficiency. I'll use the LSx cars since I'm so familair with them, but My 'bird got 28mpg and put over 430hp to the wheels, GM's Z06 is rated at 505 hp and EPA rated at 27mpg.

[Kip Drordy]

Actually, performance and milage are intricately linked via efficiency. I'll use the LSx cars since I'm so familair with them, but My 'bird got 28mpg and put over 430hp to the wheels, GM's Z06 is rated at 505 hp and EPA rated at 27mpg.

I agree with that wholeheartedly, but these machines are already super efficient in the first place. Finding other sources of mechanical inefficiencies would be a tall order.

[Dweezel]

actually the 4 valve motor is horribly inefficient. on paper it flows allot of air, but in reality, when both valves are open, the intake charge skips off the back of the intakes, right out the exhausts, not to mention the lack of swirl, and horrible plug location in a dead zone @ dead center of the chamber.

[cattmouch33]

numbers numbers on the bird. That's a lot crap to sort out to make the bike better. But hey we eventually get the benefits from it.

[Dweezel]

numbers numbers on the bird.

Huh?

[Disclaimer]

Haven't you heard? About the Bird?

[Kip Drordy]

actually the 4 valve motor is horribly inefficient. on paper it flows allot of air, but in reality, when both valves are open, the intake charge skips off the back of the intakes, right out the exhausts, not to mention the lack of swirl, and horrible plug location in a dead zone @ dead center of the chamber.

I'm saying efficient compared with other 4 valves shhish.

I thought that dead center is the ideal place for the plug. Isn't that why the Hemi is such a popular choice for big power numbers? Other than the hemispherical head of course.

I wonder when direct injection will make it's way into these machines.

[Dweezel]

no, actually high about 3/4 in is, thats about where the most air movement is at TDC, The hemi was such a popular choice because the valve angles and associated chamber shape flowed allot of air, this is also the reason modern Hemi's have 2 plugs per cylinder, about 1/2-3/4 of the way in

[tomin40]

numbers numbers on the bird. That's a lot crap to sort out to make the bike better. But hey we eventually get the benefits from it.

Agreed. Hopefully the airflow/cooling and engine design eventually gets propagated to the street bikes. Better reliability and more power.

[tomin40]

Interesting read. I like how they went into the project with goals of more power and better mileage. DuH!!! Who wouldn't want better performance in those two areas? Problem is they tend to be counteractive, more power typically = less mileage. But, obviously they figured it out and made the bike work for them.

BTW those "Click Here" links require registration. But, a good article anyways.

Yeah, those were links to the supplied diagrams that are there. Sorry, just copied and paste from the article.