Zero SR/S electric motorcycle: air change increases the range
With the Zero SRS Intelligent Aero Prototype, WMC increases the range of the electric motorcycle with aerodynamic interventions. A promising proof of concept.
(Image: WMC)
After successful tests with a radically aerodynamically improved, record-breaking electric bike in 2021, nothing had been heard from the British research and development office White Motorcycle Concepts (WMC) for a while. Now the engineering service provider is using a Zero SR/S to show how aerodynamic drag can be reduced by a whole ten percent with just minor changes to a standard bike. The prototype will be exhibited by Zero Motorcycle at the British motorcycle show "Motorcycle Live 2024" from November 16 to 24 in Birmingham.
Faster or further
The e-bike, which was redesigned in cooperation with the Californian manufacturer, now goes faster and has a greater range at higher speeds. To achieve this, the engineers used a standard Zero SR/S to create an air duct with a not at all dramatically large cross-section, which relieves the back pressure from the area between the front wheel and the steering head to the rear. The front fender and fork fairings are shaped according to aerodynamic computer simulations and direct the airflow into the horizontal duct, which splits at the level of the power electronics and battery and ends in two openings above the rear wheel, one above the other.
The space required for this on the standard SR/S could be created by mounting the power electronics higher up, above the battery. This would be conceivable with the standard SR/S by dispensing with an optional charger. If this is not ordered, there is a relatively large storage compartment above the electronics – or space for the necessary relocation of the inverter.
WMC Zero SRS Intelligent Aero Prototype I (9 Bilder)
WMC
)According to WMC, this simple measure has improved the drag coefficient of the SR/S by ten percent. If normal user behavior is taken into account (i.e. no constant high speeds), power consumption could be reduced by around five percent, meaning that the SR/S would ideally achieve 290Â km per charge in the WMTC instead of 275. User behavior is worth mentioning at this point because aerodynamic drag increases with the square of the speed. In city traffic, the improvement in aerodynamics is therefore unlikely to have any measurable effect.
WMC is thus transferring its findings from the WMC250EV project, which the company developed around its founder Robert White. He would like to set the land speed record for an electric motorcycle himself, which would be a nice advertising effect for his development office. The goal is to reach 402 km/h with this motorcycle. In the absence of a full announcement, we can assume that they are still working on it – is, after all, a matter for the boss.
Easier with the record vehicle
In the prototype for the world record, a much larger, almost straight Venturi tunnel runs between the chassis and the drive. The dimensions of the tunnel are made possible by the driver almost lying on it. This radical concept is intended to reduce air resistance by a remarkable 69Â percent compared to a traditionally constructed motorcycle, but is not realistic on a road motorcycle due to the rider's position.
Zero SRS Intelligent Aero Prototype II (7 Bilder)
WMC
)Not only electric motorcycles benefit from the channel work at WMC. A tilting tricycle based on the Yamaha Tricity 300 has also already demonstrated its advantages. With the help of hybridization in conjunction with the internal wind tunnel, fuel consumption is said to be up to 50 percent lower in comparison.
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If WMC's figures for the Zero SR/S are confirmed in real-life operation, we could soon see more electric motorcycles with central shafts. The intervention in the structures is – at least manageable with the Zero –. On the other hand, it is virtually impossible that we will soon see cars with ducts because their bodies have long been in a completely different aerodynamic league. At best, there are still a few tenths of a percent to be gained here.
(fpi)