We have previously covered attempts to break the world land-speed record for electric motorcycles – actual record-holders (Voxan Wattman) and new advanced projects (White Motorcycles) – but now ReVolt is attempting a record on a bike that was retired in 2012.

Deeley prepares for a test run at El Mirage on his partially streamlined land-speed bike, designed to break the existing SCTA record for bikes powered by electric or steam turbines. Better batteries have brought this machine out of a 10-year-plus retirement (Images courtesy of dancoronado.com)

Voxan is very well-funded, has access to Formula E powertrains through its association with Venturi and it is the current FIA record-holder in various classes with a maximum of 456 km/h (283 mph). White has yet to make an attempt on the FIA record with its striking motorcycle, but high-speed trial runs look very promising while a powertrain partner is sought.

In the US, Lightning Motorcycles has famously held the Southern California Timing Association (SCTA) record since 2011 with a highly streamlined version of its production motorcycle, but there is a new project to break records with a familiar theme that we have covered before.

In an article on the world’s fastest electric vehicle, run by Team Vesco (RET 139), we discussed its electric powertrain, provided by California-based ReVolt Systems, and its unusual ‘home’ in a car conceived and originally built in the 1950s. Matthew Deeley of ReVolt is attempting to do something similar by putting a ReVolt-engineered powertrain into an existing land-speed motorcycle built some years ago.

Bonneville record

The motorcycle is not as old as the Vesco car, having been built in 2009 by (and campaigned by) Kent Riches and Randy Nelson. Riding the bike when originally built, Nelson set the first certified record for an electric motorcycle at Bonneville Salt Flats in Utah, achieving a maximum speed of 206 mph (331.5 km/h) before it was retired in 2012, owing to battery limitations.

When Riches heard that Deeley was planning a record attempt, he offered him the use of the bike. The SCTA record, held by Lightning, currently stands at 215.962 mph (347.6 km/h), and Deeley aims to use a modified version of the Kent/Riches bike to challenge it using a different powertrain.

The bike was ready to run at Bonneville Speed Week 2023, but poor weather hampered progress, with all types of vehicles running slower than usual, owing to poor conditions on the salt flats.

Battery boost

The main difference to the original Kent/Riches powertrain is the capability of the battery. Built of 456 prismatic lithium-ion cells, arranged in four parallel strings of 114 cells, it gives a nominal voltage of about 410 V. The battery is capable of discharging at 350 kW, which is significantly more than the present capability of the drive motor.

The stripped-down machine shows a very basic bike, with the inverter under the rider’s chest, batteries taking up the entire front part of the machine and a large motor driving the rear wheel by a chain. The back of the seat is formed by a coolant tank carrying water for the motor

The battery is built primarily for energy capacity. Even though it weighs an estimated 250 lb (113 kg), its capacity is only 7 kWh, giving a relatively low energy density of about 60 Wh/kg.

The ratio of discharge power to battery capacity gives a C-rate of 28.5, which is uncommonly high, but this is a very unusual usage case, and the battery is never run from fully charged to fully discharged at this rate.

Deeley thinks that discharging to 40% would be typical for a long run, followed by a relatively long, slow recharge. He says the cells, taken from a Honda Insight production car, “are not getting stressed and not getting hot during a run”. On top of the prismatic cells are M6 studs, which connect them to copper busbars.

Back when the bike was originally built, the battery was the limiting factor for power and speed, but that will not be the case this time around.

Torque and traction

The propulsion motor is an improved-performance version of the original UQM Power-Phase 150 motor and is now capable of delivering 200 kW, rather than the original design output of 150 kW. It is a permanent-magnet, three-phase AC machine, with the magnets mounted on the surface of the rotor.

The UQM motor is usually used in light or medium-duty commercial vehicles or buses, and it was certainly not created for motorsport or breaking records. Deeley says the increased power has come from improvements in the control of the motor, rather than doing anything mechanical internally. This allows the motor to run a little faster, but with “a significant increase in torque”.

With this extra torque, Deeley says the constant headache of poor traction on salt will become worse. Even at very high speeds, it is possible to spin the rear wheel, so real care and attention must be taken. “Poor traction is the cause of a lot of accidents,” he adds.

Cool runnings

With the motor being so big and heavy, Deeley says it has a lot of thermal mass, and it can be run flat-out for as long as he will ever need it to before it becomes limited (in a thermal sense). The motor is cooled by a tank of cold water (rather than water-glycol), which is recirculated back into the tank sitting right in front of the rear wheel.

The motor runs at a relatively low speed, about 5000 rpm maximum. A sprocket on the motor output drives a second sprocket on the rear wheel via a conventional drive chain.

After being run in the salt and then left to stand for years, some aspects of the bike suffered accelerated damage from the ravages of time. The wiring loom in particular was in bad shape.

With a significantly more capable battery, the supply of power to the motor is no longer causing a bottleneck, and there is certainly enough headroom to provide power to a more capable motor if one should be required later to improve performance.

However, for the present time, being able to continuously provide sufficient power for the motor while running at maximum performance should enable the team to improve on the 206 mph originally set, and hopefully beat Lightning’s long-standing benchmark.

Dry lake testing

To get a licence to race at record speeds, Deeley has been running the bike at El Mirage dry lake. This has provided useful testing, allowing the rider and wider team to learn more about the bike, and resolve any minor problems. Even allowing for poor weather and track conditions, the team have done enough running at low power to top 170 mph.

Deeley says: “There’s no doubt in my mind that we have the power to go over 230 mph when the racing season comes back around.”

He will next run on a relatively short course at an El Mirage meeting in May, before attempting to beat the land-speed record at Bonneville Speed Week in August on the longer course, where speed can be built more gradually.