Professional sports have long been plagued by doping and professional cycling is no exception. This culminated a few years ago when Lance Armstrong, seven-time winner of the Tour de France, suffered what may have been an athlete’s longest fall from grace for taking performance-enhancing drugs (PEDs).
The cloud of doping still looms over cycling, but another form of cheating called mechanical doping has been thrust into the spotlight. At this January’s world championship of cyclo-cross, a gritty version of road racing that gives pro cyclists something to do in the winter, suspicious race officials dissected the bike of 19-year-old Belgian cyclist Femke Van den Driessche. Hidden in a tube of the bike frame was an electric motor.
Cycling had been on high alert for mechanical doping and now had the proof. But whereas physiological doping reached its lowest with the help of doctors, mechanical doping will enlist engineers.
A History of Cheating
The Tour de France is part of cycling tradition. Over a hundred years old, it has been interrupted only by a world war. Drugs in cycling are an even older tradition. Accounts of early days reveal use of strychnine (small doses work as a muscle relaxant), amphetamines and cocaine taken openly by cyclists before rules were made against it.
A lot has changed. The Tour de France has gotten longer (from six days to over three weeks) and faster (average speeds approach 30 mph) to become what is arguably the world’s most grueling sporting event. Modern medicine has played a part. Doctors have helped with training and nutrition but have also been found complicit in blood doping and use of prescription drugs like EPO, testosterone, human growth hormones and anabolic steroids to name a few.
Engineering has also lent a hand. Bikes are lighter and stronger as a result of design, materials and aerodynamics. But, as with medicine, cycling can use engineering for nefarious purpose.
Rumors of Mechanical Doping
Rumors of motorized bicycles in races have swirled for years. YouTube is replete with odd happenings for which cheating is offered as the only explanation. There is a rear wheel that spins on its own long after its rider has been unseated. Accusations have been leveled against riders who display extraordinary and unexpected performance, such as suddenly bursting out of a pack of riders already going full-tilt. A hand movement that suggests activating a hidden switch is played over and over. A grainy video in Italian, complete with CAD animations, shows how a racing bike can be fitted with an electric motor. It has been watched almost five million times.
Without real proof, believers in mechanical doping were in danger of being grouped in the same category as UFO sighters, conspiracy theorists and prosecutors without a smoking gun. The most tantalizing evidence came from journalists who staked out a race and used a thermal imager disguised as a video camera to find several suspicious hot spots. Unfortunately, neither the bike, rider or team was identified.
Cycling’s regulators, scorched repeatedly by drug scandals on their watch as well as allegations of collusion with teams and riders, were on a mission to be seen as watchdogs to prevent this next big taint to their sport. Using airport-style X-rays machines, visual probes and ultrasonic testing, they have partially disassembled hundreds of bikes looking for hidden motors. The UCI, the governing body of international bike racing, claims to have tested over 10,000 racing bikes over the last five years. Until Femke rode a Wilier bike with a secret electric motor option to try to win the women’s world championship of cyclo-cross, they had come up empty-handed.
Finally, the bike racing world had its smoking gun.
The Engineering of Cheating
Motors to power bicycles for commuter and recreational cycling may be the hottest thing in the cycling industry right now. “E-assist” bikes have breathed life into an industry that is fairly low-profit, low-glamour and possibly saturated. They are marketed to the commuter who can leave his SUV in the garage and still get to work without breaking a sweat. They could help older or less fit riders save face on group rides, proving grounds for weekend warriors. This technology is not to be used for racing, they insist.
After the Femke fiasco, the question is no longer if the technology will be used in races. The new questions are: Where next? How much mechanical doping is really going on? Does this start a new game of cat and mouse, with engineers on both sides; one side perfecting hidden power devices and the other finding ways to detect them?
How It Works
Racing bikes can be fitted or designed with small electronic motors that add power to the bikes’ drive trains. The Vivax configuration involves a motor tucked into a tube of the bike frame, undetectable by the naked eye. A switch to activate it can be hidden anywhere within reach, with the wiring out of sight, brought into the tubes of the frame. A wireless design, such as Bluetooth, would be even sneakier. A controller, a slim PCB, can be hidden in the bike. A large battery, good for a couple of hours at a low power setting, can be disguised as a water bottle, but, for the utmost discretion, batteries would be shaped to be hidden in the frame of the bike along with the motor.
Bicycle racing has long benefited from technology. It’s not uncommon for professional teams to undergo wind tunnel tests and use CFD to perfect not just their form but the formation of the entire team. The design of carbon fiber bike frames has resulted in frames so light you can lift them with a finger.
The Vivax Connection
In a test with professional cyclists, an electric motor was said to have no resistance when not turned on but has a “strange feeling” when backpedaling. The Vivax Assist was also emitting a discernible sound, though maybe not enough to give itself away in a race situation.
The Vivax motor provides 60 minutes or 90 minutes of power, depending on the setting.
Alternatives to Vivax
Whereas the Vivax system is said to be a bit noisy, it may have been an engineer that offered a quieter alternative. The New York Times interviewed one such person who bragged that his smaller, quieter motors were virtually undetectable and he was taking custom orders for anywhere from EUR€10,000 to €25,000 (USD$11,000 to $28,000).
Another mechanical drive system for bikes powers the rear wheel hub. Several commercial electric-assisted bikes employ this system but hub-drive systems make for a very noticeable large hub that would be a dead giveaway in a race.
Another design uses magnetic induction. Magnets on the wheel rim can be moved by coils on the bike frame. Engineers in home workshops will show you bike wheels with evenly spaced magnets on the rims. Get the wheel spinning and power the coils and the wheel picks up speed. E-bike enthusiasts have touted this technology as the future of power-assisted bicycles because it has fewer moving parts and a silent operation. It is expected to be expensive and relatively low-powered.
One bike manufacturer, Lightweight, is using the “Mag-lev” principle on a working prototype and claims a whopping 500 W with a top speed of over 60 mph—which the company promises to limit to less than 30 mph for the rider's safety. No price for this model has been stated at the time of this writing.
But with the technology proven and usable, it may be only a matter of time before engineering finesse makes it smaller, quieter and more affordable.
Technology to Catch Cheaters
A number of detection schemes can be used to detect power-assisted bikes. This includes visual inspection, airport-style x-ray machines, ultrasonic testing, thermal imaging and magnetic flux detection.
Thermal imaging, which detects infrared (IR) radiation most closely associated with heat, can be done by pointing to a bike with a device with a sensor. A handheld IR camera for professional use can cost a few hundred to a few thousand dollars. Though most have a pistol grip, they can take on a variety of shapes. They range from tiny, in-home motion sensors to portable units that look like regular cameras up to FLIR (forward-looking infrared) pods attached to aircraft.
Thermal detection of an electric motor during a bike race is maybe the simplest and most effective technology in theory. A bike, even in racing conditions, will generate little heat as there is very little sliding friction (a little in the links of the bike chain and in the between the wheel and the brake pads). The heat generated with rolling resistance from mechanical components and the tires against the road would be almost negligible. A working electrical motor would be a clear hot spot.
Wires would also be a sign. Some configurations involve hiding a battery in a saddle bag, on the person, or in a specially adapted water bottle, so external wiring and entry points into the bike frame would also be an indication, even if the battery was thrown away.
Detection with an iPad
So far, the UCI has tested over 10,000 bikes by various means and has settled on a “tablet teslameter” device to detect magnetic fields. A teslameter is another name for a magnetometer.
The UCI claims its specially developed device, which appears to be an iPad in a special case, can detect both hidden motors and magnetic wheels using magnetic flux density detection. According to acing publication Velonews it also has a scanner that creates a magnetic field and the device is able to detect any changes in the field “which can come from motors, magnets or a solid object such as a battery concealed in a frame or components.” In a statement sent to Cyclingnews, the UCI claimed that "by far the most cost-effective, reliable and accurate method has proven to be magnetic resonance testing using software we have created in partnership with a company of specialist developers."
The advantage of this device is that it can be used on “cold” bikes, allowing the officials to test bikes en masse on team cars, gathered before the race, or long after the race is over. However, magnetic field density drops by the distance cubed, exposing what is a magnetometer’s biggest disadvantage: It has to be held close to the bike, making the device practically unusable during a race.
The UCI device was used earlier this year in another Grand Tour, the Giro d’Italia, but no mechanical doping was found.
Flaws in the Detection System
Critics say the UCI method, which has so far found only one culprit, is inferior to IR imaging cameras. A pair of investigative journalists using an IR imager disguised as a video camera was able to spot what they say are seven hidden motors. The point-and-shoot system simplicity with an easily interpretable image is also much easier to grasp than 3D scanning and magnetic field detection.
A device that is not usable during a race could also be fooled by strategy. A cheating rider in a race in which bike changes are allowed could start the race with a clean bike, use a power-assisted bike for most of the race, switching back to the clean bike near the finish.
Greg LeMond, triple winner of the Tour de France and outspoken critic of physiological doping, called the UCI to task, saying it is not doing nearly enough to stop what he sees as the next big scourge of cycling. A relatively small percentage of bikes are tested, few during the race itself. Bike switching during races that occurs after a mechanical failure is deemed acceptable, but sometimes switching occurs for no apparent reason and this has aroused suspicions. Sources say the UCI will restrict bike changes to “listed” bikes. LeMond also recommends a variety of detection technologies, rather than relying on a single one, whatever that might be, presumably to keep cheaters on their toes.
Tour Shutting the Doors to Mechanical Doping
A frenzy of media attention has put the Tour de France under a microscope and that by itself may be enough to prevent mechanical doping of any recognized form. Every cycling journalist with the means to obtain a IR camera will be looking for a career-making scoop. Race officials have been spotted using IR cameras themselves during one stage and now appear to be supplementing their magnetometer-driven strategy.Current known designs for mechanical doping schemes may have met their match at the Tour de France.