Tag Archives: aerodynamics

Honda patents aerodynamic tail

Honda has filed an application for a patent for an aerodynamic tail that looks a little like those spoilers we see on “sully sic” fast fours and 1970s supercars.

Winglets have been added to the front of MotoGP bikes over the past couple of years to address aerodynamic issues.

Now Honda is looking to add some aerodynamic assistance to the rear of the bike.Honda aerodynamic rear end

Aerodynamic tail

Ducati’s Panigale V4 has a similar aerodynamic trail.

Corbin motorcycle seatsDucati Panigale V4

However, Honda’s patent features a removable tail-pack, where you can store small items such as your phone or wallet. That seems to indicate it’s not been designed specifically for race use.

It also appears to have movable wings which could be deployed at high speed for stability and under heavy braking to keep the rear wheel on the ground.

They could be deployed automatically or with a manual switch on the handlebar.

It would match the active aerodynamic winglets Honda has also applied to patent.

Honda patents active aero directActive winglets patent

Aerodynamic issues

Now don’t laugh. Aerodynamic issues are more prevalent in motorcycles than cars.

The most aerodynamically “slippery” motorcycle is the Suzuki Hayabusa which has a drag coefficient (cD) of about 0.55 to 0.60.

Hayabusa GSX1300Hayabusa

Drag coefficient is the ratio of drag on the body moving through the air to the product of the velocity and the surface area of the body.

Even a Mazda6 sedan has a much better cD of 0.26.

Racing engineer Jeromy Moore says it is difficult for motorcycles to match a car’s aerodynamics, because they are too short.

“With aero, it will be hard to get a bike’s cD down as it is quite short so the air has to deflect at larger angles to go around and rejoin,” he says.

Honda patents

This is one of a blitz of patent applications by Honda over the past couple of years.

Some are quite weird and impractical, but others may actually make it to market.

We suspect Honda is just trying to dominate intellectual property on motorcycle inventions, rather than planning to put them all into production.

The patents include:

Forks Goldwing patentGoldwing forks patent

Source: MotorbikeWriter.com

How to squeeze out more fuel economy

Most motorcyclists are not too concerned about fuel economy, but there may be times when you need to ride more economically just to make it to the next service station.

A few years ago, we miscalculated fuel economy on a Harley-Davidson ride to the Iron Run rally in Queenstown, New Zealand.

The low-fuel lights flashed on the bike Heavy Duty editor Neale Brumby was riding as well as mine while we were in the remote forest section on the west coast of the South Island.

We had no idea how far it was to the next service station, so we went into fuel conservation mode.

It was actually fun, if dangerous, as we switched off the bikes for downhill runs, kept corner speeds high and took turns at closely draughting each other.

In fact, we strongly advise you to never switch off your engine while moving!

Some bikes have servo-assisted brakes that require power to operate. It could also cause a rear-wheel lock-up when you switch back on and re-engage the drive.

You will also lose the use of crucial safety features such as brake lights and indicators.

Fuel economy tipsTriumph Bonneville fuel economy rules service station fuel economy

There are much safer ways of conserving fuel if you are ever in the same situation, something more likely in remote areas of Australia’s outback.

Momentum and aerodynamics are the most effective ways of reducing fuel consumption.

Acceleration chews fuel, so you need to keep the momentum going and avoid heavy braking.

That means smooth and light acceleration before you reach the bottom of a hill so that you don’t loose too much speed and need to accelerate hard to get up the next hill.

Keep that momentum going and your speed fairly stable.

Aero hurdle

One of the biggest hurdles to motorcycle fuel economy is the aerodynamics of the machine and rider.

Even aero-dynamically designed motorcycles like the Suzuki Hayabusa are not very aerodynamic when a rider sits on them.

So it is important that the rider crouches down over the tank to decrease their wind resistance.

Check the official fuel economy figures for your motorcycle. Some companies actually list them for various speeds. That’s because they can vary substantially with speed.

Most motorcycles will have optimum fuel consumption figures around 80km/h, thanks to the aerodynamics of a motorcycle, so stay around that speed.

Otherwise, if you are riding in remote areas of Australia, it is a good idea to carry a 5-litre jerry can of fuel.

Even if you know there is a service station 300km down the road, it may not be open, it may be out of fuel, or, as I once found, the electricity is out and they can’t pump the fuel!

Source: MotorbikeWriter.com

Aprilia RS 660 concept is half a Tuono

Aprilia has cleverly taken half a Tuono engine and made what they call an RS 660 Supersport twin concept machine.

It is powered by two cylinders from a Tuono/RSV4 1100 engine as a 660c parallel twin.

“This configuration was chosen for its compact nature and efficiency, the extremely low level of heat transmitted to the rider and for the freedom that it leaves the designers to create a sleek and lightweight frame and suspension,” Aprilia’s press release says.

The Austrian company says the RS 660 project is aimed at younger riders and shows the supersport market may not be quite dead yet.

They say it will also be the “development base for a wider range that intends to make Aprilia a key player in an extremely strategic market segment in Europe, but also in Asia and the American market”.

Although not mentioned, we should expect to see it in Australia to compete against the very popular mid-sized naked sector led by the Yamaha MT-07.

RS 660 aeroAprilia RS 660 concept is half a Tuono

Aprilia says the Concept RS 660 was developed out of a “series of aerodynamic studies” in a wind tunnel.

With fuel economy top of mind and emissions regulations tightening, motorcycle manufacturers are looking for ways to compete and aero remains one of the biggest hurdles to motorcycles, even more so than big, bulky cars.

Click there to find out how aero affects motorcycles.

Aprilia’s Concept RS 660 features a unique “variable front section” which can adjust air flow direction to vary downforce.

RS 600 has a large saddle and a comfortable riding position to suit most rider sizes.Aprilia RS 660 concept is half a Tuono

It is supported by a lightweight aluminium frame and swingarm with the engine as a stressed element.

The right arm of the swingarm has a curved shape to accomodate the exhaust, while the shock absorber mount is mounted directly to the swingarm with no linkage to reduce weight.

Source: MotorbikeWriter.com