Cheating in Bicycle Races with Tiny Hidden Motors

If doping weren’t enough, cyclists are cheating in races by hiding tiny motors in their bicycles. There are many detection techniques:

For its report, Stade 2 positioned a thermal imaging camera along the route of the Strade Bianche, an Italian professional men’s race in March held mostly on unpaved roads and featuring many steep climbs. The rear hub of one bicycle glowed with almost the same vivid orange-yellow thermal imprint of the riders’ legs. Engineers and antidoping experts interviewed by the TV program said the pattern could be explained only by heat generated by a motor. The rider was not named by the program and could not be identified from the thermal image.


Cycling’s equivalents of the Zapruder film are online videos that show unusual patterns of bike changes that precede or follow exceptional bursts of speed by riders. Other videos analyze riders’ hand movements for signs of switching on motors. Still other online analysts pore over crashes, looking for bikes on which the cranks keep turning after separation from the rider.

Unlike the thermal images, however, the videos have only implied that a motor was present.

In a statement, the cycling union, which commonly goes by its French initials, U.C.I., said it had tested and rejected thermal imaging.

“The U.C.I. has been testing for technological fraud for many years, and with the objective of increasing the efficiency of these tests, we have been trialling new methods of detection over the last year,” the governing body said. “We have looked at thermal imaging, X-ray and ultrasonic testing, but by far the most cost-effective, reliable and accurate method has proved to be magnetic resonance testing using software we have created in partnership with a company of specialist developers.”

Posted on April 22, 2016 at 6:22 AM48 Comments


Christian April 22, 2016 6:50 AM

A friend of mind told me a year ago that X-Rays for bikes in Races have become common practice.

Clive Robinson April 22, 2016 6:56 AM

@ Bruce,

There is a funny side to “thermal imaging surveillance”…

One way to detect hidden surveillance devices is via thermal imaging.

The usual technique is to empty the room of people having pulled down the blinds and turned the aircon to maximum chill.

When the room has dropped to an overall chill go in with the TI and have a scout around for warm spots from energy being used.

If that does not give an indication whack the thermostat up to max and keep scanning around.

In general surveillance devices do not have the same thermal charecteristics as the items they are hidden in. Which means as the tempreture goes up they either lead or lag the temprature of the object, thus they appear as small thermal difference points, that with care can be spotted.

Further frequently surveillance devices are “conductive” whilst the objects around them are not. As was noted well over a century ago, eddy currents cause measurable changes in objects and the signal generator. It’s the principle behind RF heating and metal detectors.

Whilst there are ways to reduce the effects by drilling very fine holes and using them as audio transmission lines they need carefull matching to work well and thus there are few people around who can deploy such audio bugs. And from the perspective of the person doing surveillance you don’t even have that with video unless you use specialised fiber optics which have their own problems.

Thus unlike other “bug detecting” equipment, the thermal imaging method tends not to “tip off” the surveillance operative you are searching for their equipment.

Clive Robinson April 22, 2016 7:05 AM

OH I forgot to mention “magnetic resonance testing” works by measuring energy loss from the test instrument into the device which is basicaly just another form of eddy current measuring (except it gets an advantage by the self resonance of the object under test, much as you can do with sound and wine glasses).

Tim Bradshaw April 22, 2016 8:52 AM

I wonder about this. A professional cyclist can average 5W/kg for an hour, so if they weigh 50kg this is 350W. How much energy can you store in a sufficiently small battery to fit inside a frame tube and not make the bike seriously heavy? What is the power output of an electric motor which can easily fit inside a hub?

As for hubs getting hot: there’s this thing called friction which even the best bearings suffer from.

I suspect this is nonsense.

x2bike4u April 22, 2016 9:00 AM

@Tim Bradshaw

Even a 10% boost (25 – 35W) for say 5-10 minutes at the end of a long race can be enough to allow you to keep up with or pull away from riders around you.

Snowflake April 22, 2016 9:11 AM

@Tim Bradshaw: Friction alone doesn’t adequately explain it. For a group of riders in a race, all going the same direction at the same time at (about) the same speed, you’d expect them all to have about the same amount of friction… Unless a professional cyclist somehow forgot to lube his hub, and yet was still able to ride that unlubricated hub for an entire race without it failing. The catch is when you thermally image a pack of bikes, and one stands out conspicuously from the others… You know something is different about that bike.

@Christian: X-Rays for the bikes are great for catching internal shenanigans, but on some of these longer rides, bikes are swapped multiple times during the race, and while the standby bikes are on standby, they’ll pull them into the car and do work on them to get them ready in case they need another swap. Not hard to see how parts could get added/removed without anyone seeing it.

wumpus April 22, 2016 9:25 AM

If one bearing had significantly more friction than all the other riders, that rider would quickly fall back and lose. Magnetic resonance testing is obviously ideal as long as you assume that the bicycle you are testing is the same as the one ridden in the race, making sure this is not the case is one of the oldest tricks in the book (I’ve heard claims it is the basis of nearly all stage “magic”). Infrared has the advantage of being trivially moved and always capturing the bike being used, I can’t see U.C.I. suddenly laying down magnetic mats in the middle of a race to capture magnetic induction data, or suddenly having a bunch of lanes that resemble airport magnetic detection.

The Tour de France takes roughly 100 hours to complete. The last time the runner up was more than 10 minutes behind was in 1984. A 10% advantage during a sprint or breakaway would easily make the runner up win (probably let anybody who kept up with the peleton win, for sufficient lengths of “10%”).

albert April 22, 2016 9:30 AM

As usual, I get a laff out of ‘cheating at sports’ news. Again, abuse of technology.

If the bicycle racing authorities get tired of all this, I have a suggestion: Take the hardware out of the system. Follow the GP2 example. (It’s a ‘feeder series’ for young drivers who want to enter Formula One racing). All cars a built to a rigid specification by one manufacturer, and no modifications are allowed. Added devices could be detected by simply weighing the bike, (unless someone develops an anti-gravity system:)

So athletes, keep on cheating, and keep marginalizing your sports, ’till you end up like professional wrestling, or bad reality television*

  • OK, perhaps the ‘bad’ is redundant.
    . .. . .. — ….

wumpus April 22, 2016 9:31 AM

@er, edit that last statement on Tour de France. The idea was that you could presumably recharge your motor multiple times, thus giving you a 10% advantage for a few minutes each day.

Note that I suspect that motors this small can’t do regenerative braking (typically a feature of larger induction motors). But at the upper levels, it might be worth the R&D to either get a smaller one to recharge by braking or make an tiny inductive motor (that would likely get by magnetic sensors looking for rare earth magnets).

They do brake in the Alps, don’t they?

Comrade Misfit April 22, 2016 9:33 AM

So, the one method that is the best tool for detecting illicit motors is the tool that the ICU doesn’t want to use.

That suggests to me that they really don’t want to know who’s using the motors.

KevinH April 22, 2016 9:51 AM

Regarding battery capacity versus weight–the energy density of modern batteries is actually pretty good. Since it’s easy to find the numbers online, I’ll look at a modern mobile phone battery. The iPhone 6 Plus battery is rated at 11.1 watt-hours, and weighs 43 grams (1.5 ounces).

If we want a 10% boost to average power (30 watts, as suggested above) that little iPhone battery can keep it up for 20 minutes.

If we add a full pound of those batteries, we can have a 10% boost for more than 3 hours, or double our hill-climbing power for more than 20 minutes.

In other words, the energy available definitely more than offsets the added weight.

Mike Barno April 22, 2016 10:15 AM

@ Tim B, KevinH :

It says right in the article that the installed systems are light enough to keep a bike down to the minimum weight.

Matthias U April 22, 2016 11:21 AM

There’s only one possible reason for rejecting thermal imaging: the UCI doesn’t want yet another scandal, so they try to hide it all under a convenient rug – forgetting that the longer they do it, the worse the scandal will be when the bump under that rug becomes too noticeable. Apparently, learning from past mistakes is something other people do.

There is no fracking way an abnormal thermal signature can be caused by anything other than a motor. The only other possible source of heat is friction. No sane pro cyclist would ride a bike that converts any noticeable part of his work to heat for longer than ten seconds.

WRT regenerative braking: What braking? the whole point of the Tour is to be as fast as possible. Slowing down is not part of the agenda. When the battery is flat, the rider can just switch bikes. That being said, I do wonder whether the part count for a regenerative motor is all that greater, these days.

Wael April 22, 2016 12:08 PM

The great pattern detective (none other than truly yours) noticed @Bruce’s peculiar interest in cheating and gaming the systems lately. Ok, to make a long story short, I suggest a title for the skunkworks book you’re working on, before you even ask:

Sticking it to the Man, the natural response to Data and Goliath 🙂

You leaked too much info 😉

r April 22, 2016 12:24 PM


Maybe helium in tires? Proudly wouldn’t stay very well but you can lower weight that way… Maybe welded and sealed into the tubular frame.

r April 22, 2016 12:26 PM

Ofc some bikes are carbon fibre aren’t they? Not sure how well that could be vacuum sealed/hydrogen filled.

paldubee April 22, 2016 1:01 PM

We should start a new race called, “Tour De Farce“. The winner is the best one at cheating.

Mark Allyn April 22, 2016 1:13 PM


As a bicyclist, I am very embarrassed by our sport each time I read stories like this.

Why is bicycling one of the most cheated sports around?

I use no drugs and I use no motors and I have a fine time bicycling my 40 mile round trip commute (Portland, Oregon to Intel in Hillsboro, Oregon).

I think that cheats like these should be banned from bicycling for a long long time!

Mark Allyn
Portland, Oregon

Gerard van Vooren April 22, 2016 1:37 PM

@ r,

Sorry, carbon fibre is micro porous. The helium will escape. And I am quite sure that it will escape in rubber tires too. If the tubes are from metal then it could work. It reminds me of the early seventies Porsche 917 Le Mans sports prototype car with a tubular spaceframe of only 42 kg (and the car did have approx 1000 bhp). They pressurized the frame and placed a manometer. So the driver could check the integrity of the frame while driving the car at 360 km/h (220 mph) on the Mulsanne Straight.

Snarki, child of Loki April 22, 2016 2:14 PM

“Magnetic Resonance Imaging” as in MRI, as in “NMR for people who are scared of the word ‘nuclear'”?

If so, no surprise that they didn’t see anything. NMR will only show them the hydrogen (or perhaps 13C) content inside, so great if they want to find organic stuff, but “motors” are typically made from stuff like copper and other metals.

Has anyone tried the “take it apart and see what’s inside” approach?

John April 22, 2016 2:21 PM

UCI has a minimum weight for bikes, about 6.8Kg I think. It’s not hard to make a bike lower than this so there is some adding of ballast to meet the minimum but of the order of a couple of hundred grams. Remember that a classic race of a stage of a major tour is 5 or 6 hours and in the sprint finish or a major climb the rider’s power output is going to be 1kW or more not the average of 300W suggested above.

So the back of an envelope calculations above underestimate the weight significantly and the rider would not be happy carrying all that weight for the hours before its needed.

Nor would it be easy to hide all those batteries in the tubes.

The bottom bracket is pretty full of stuff too no real room for a motor.

A cracked bearing in the bottom bracket could easily generate enough heat and the rider might well ride on it for a while until he can get a new wheel.

Also could have been a disc brake which are being experimented with and heat up pretty quickly.

Gerard van Vooren April 22, 2016 2:37 PM

@ John,

You are missing one important argument and that it is confirmed that this technology actually exist. It is no fiction. People have been caught with it.

suferick April 22, 2016 2:43 PM

@ Matthias U:

Braking is an important part of pro cycling, and a hot technical topic in itself at the moment. Disk brakes are being used by some teams for the first time this year, amid safety concerns, but all brakes are fully visible and open. I don’t know how regenerative braking works but I’m not sure it would be viable. Descending, including braking, is a vital component of a successful cyclist’s armoury – arguably it was superior descending skills that enabled Peter Sagan to stay clear of his chasers and win the world road race championship last year.

Allegations of a hidden motor are not new; in 2010 people pointed the finger at Fabian Cancellara when he won the Tour of Flanders in an impressive manner, riding away from three time winner Tom Boonen as if he was standing still, and again when he dominated the Paris-Roubaix classic a week later. This allegation proved groundless but similar suspicions get resurrected quite often.

A motor would confer an extra burst of speed for a short time, which could be used as a critical stage of a long climb where, if a rider could open up a short gap to his main rivals, he could expect to gain up to a minute or even more, quite quickly, and then its work would be done. A rumoured maker of such motors has said that they would be especially helpful for a rider who used a very high cadence (i.e.who turned the pedals very fast in a low gear) in the manner of a certain, now disgraced, ex-professional who also more demonstrably relied on other forms of lawless assistance.

albert April 22, 2016 3:07 PM

Technically, helium -would- make it a tiny bit lighter. For a gas, helium has great thermal transfer properties(useful for spreading the motor heat throughout the frame), but it is very difficult to contain. It’s used for super critical leak detection. How about a hydrogen/air fuel cell instead of batteries? (Hey, Joe, is that water coming out of your bike?) Or compressed nitrogen driving a tiny piston engine? puff..puff..puff..”I think I can, I think I can, I think I can.”

Batteries can be built in any configuration you desire, as can motors; for example, long & skinny to fit inside tubes.

Regenerative braking uses the wheels to drive a generator to recharge your batteries, instead of burning it off in brakes. Typically, the generator is combined with the motor (motor/generator). Everything is controlled electrically; all you need is a motor/generator. Though the front takes the brunt of braking energy, designing a system for the front wheel would be devilishly difficult, if you want to fool the inspectors, that is. 🙂

@Bike Experts,
What’s with this ‘changing bikes’ business? I can’t think of any other wheeled racing that allows you to change your vehicle mid-race. That’s crazy, and it bears no relation to anything normal in cycling. What’s needed are strict technical specifications and inspection procedures, and a design that can withstand a whole race.
. .. . .. — ….

Mike Barno April 22, 2016 3:29 PM

The mention of adding ballast to meet the sanctioning body’s minimum weight brings questions to mind. Can ballast choice lead to an advantage?

“Rotating weight.” The physics of angular momentum indicate that a rider could speed up and slow down quicker with lighter rims, tires, hubs, cranks, and pedals. I’m on the opposite side of this issue, because I ride an off-road fatbike with four-inch-wide tires at low pressure to flex over rocks and roots while maintaining grip for steering and braking. But I assume that serious on-road racers who use carbon-fiber frames also use exotic materials for their narrow rims and other parts, then add more ballast in the frame, is that true?

“Weight distribution.” In auto racing, carbuilders try to remove weight from the upper body, roll cage, and other high areas, then meet minimum weight by adding ballast as low as possible, to reduce weight transfer on corner entry. This is taken to an extreme in the class called Supermodifieds in New England/New York, in Ohio/Michigan, and on the West Coast. Because these cars race counterclockwise on ovals, they have engines and drivelines far to the left, with the driver sitting on the right. The static weight is biased far to the left, to make tire loads under hard cornering close to equal. This even load distribution allows each tire to be pushed to its limit.

I don’t imagine that a bike’s basic packaging allows oval board-track racers to bias weight to the inside. But for road racing, can ballast placement make a difference? I can imagine a bike might rotate better if its weight is concentrated nearer the middle, rather than out front and back like a car with heavy 1970s 5-MPH bumpers.

suferick April 22, 2016 5:10 PM

Changing bikes is most common in races where there is a considerable portion of flat racing followed by a period of climbing. It enables a different setup (gear ratios, for instance) to be used for the climbs and could confer an advantage for the rider. I have seen it used in time trials as well for the same purpose. I always wondered why the rider bothered (since he would lose time on the bike change) but now it makes me wonder whether something more was going on…

Sidamo April 22, 2016 5:36 PM

@john sustained climbing wattage on final climbs in Grand Tours is around 6.2W/kg, with the top guys weighing 60-67kg, so sustained rates around 370-420W.

Everyone is on their limits at that point, so even 20W extra for 5-10mins could be enough to drop everyone and win.

As for the sprint, the top guys are putting out 1600-1900W, but it’s only for a few seconds (André Greipel’s peace 2sec power was 1670W at the end of a recent race), so again, not much extra power is needed. Perhaps an extra 250W for 20sec?

Finally, the UCI weight limit is 6.8kg, but you can buy a top-line race bike right now which weighs 5.4kg out of the shop, so there’s 1.4kg of “ballast” to be added before you can race it in a World Tour event, so adding a powerful enough battery isn’t a problem from a weight point of view.

As for these latest claims, they seem to be a bit of a storm in a teacup. Plenty of people claim it has happened (a motor being used in a race) but no-one has any evidence and these heatmap videos seem to show v. slight heat increases in the precise areas you’d expect heat increases due to friction. Indeed, one of the main cycling bloggers who watched the original TV show making the claim, pointed out that at least some of the heatmap footage was of a 60yr-old rider demonstrating for the camera, NOT of any race footage.

Frank Wilhoit April 22, 2016 6:04 PM

At a previous workplace, I used to see a bike, parked in the rack outside, that had been modified by mounting the engine from a gasoline weed trimmer on a bracket. The engine’s output shaft had a knurled steel driver on it, something over an inch in diameter, and the engine bracket pivoted against a spring so that a hand control could bring the driver into contact with the rear tire. I never saw this rig in operation and can’t imagine how it would work: I would think it would just very quickly burn a hole in the tire and be done. It is just possible that the whole thing was an elaborate sight gag.

Mike Barno April 22, 2016 7:54 PM

@ Frank Wilhoit :

No joke, such setups have been around since at least 1913 with gasoline-burning engines, and in recent years with electric rigs as battery energy density has improved. I see one cruising along local roads at 15 to 20 MPH almost every day. In contrast, I hardly ever see the belt-driven or chain-driven mopeds that became popular in the USA during the 1970s energy crisis.

r April 22, 2016 10:04 PM

@Mike barno,

We have alot of both the classic style direct drive mopeds and ‘power assist’ bicycles here in Detroit. I’ve thought about buying one of those electric front wheels for my 2 cycle power assist frame just for giggles. I priced the electric front wheel kit out they’re $300 while a Chinese power assist diy rear clutch kit is ~$120.

I’ll ignore the socioeconomic observations here.

I love bikes, cheating on this sport is despicable – they should create a modders sport… I remember the solar powered bikes/’cars’/ultraultralight planes of the 90s.

Drone April 23, 2016 12:00 AM

Gave up on sports long ago, it’s become too crooked and greedy. Just about to give up on my country’s government, for the same reason.

Jon April 23, 2016 12:16 AM

One remark on ‘size of regenerative systems’. No. A motor by definition if backdriven is a generator. The electronics required to put that power back into a battery could fit on my thumbnail for the motors we’re talking about here.

I also find it completely impossible to believe that the IR cameras didn’t have a visible light camera right beside them recording also. “Rider could not be recognized on the IR” is laughable as excuses go.


Abigail April 23, 2016 5:44 AM

@Tim Bradshaw The motors exists, and are for sale in some bike shops. They’re used by aging amateurs cyclist to keep up with their club mates when touring around. They won’t give the output of a professional cyclist, but that’s not necessary. A 10% boost at the right moment can make all the difference.

But I think Bruce’s claim “cyclists are cheating in races” is a bit premature. So far, only one case cyclist has been caught: a young (16 years, IIRC) female Belgian cyclo crosser. While allegations professional cyclist use motors have been made for decades, noone has been caught yet.

Abigail April 23, 2016 6:06 AM

The MotoGP, the highest form of motor cycle racing, allows changing bikes mid-race under certain conditions (if it starts raining for instance).

Changing bicycles during the course has a price: you need to wait for your teams car to arrive, you have to stop, get up to speed again, and by the time you’re back on the bike, you’ve lost contact with the group you were in — which requires quite an effort to get back to. While there are some exceptions (for instance, if you have a race which starts with a few hours of flat terrain, followed by some steep mountains), cyclist usually don’t change their bike, unless the bike has a mechanical failure.

There’s one type of cycle racing however, where cyclist change bikes many times during the race: cyclo cross. This winter event typically uses unpaved terrain, which is often quite muddy — the cyclist often have to dismount and run with their bikes for a while. They typically have three of four bikes, changing their bike every lap, with someone cleaning their bike before it gets used again. This is necessary otherwise the mud and dirt will eventually stop the bike from operating.

albert April 23, 2016 11:13 AM

Thanks. In F1 racing, tires are changed several times in a race. Most of the time, it’s for wear, but there are two compounds for wet weather. That’s a valid point. Same for mud. Again, these are specialized races (like auto rallies, where you have one set of tires for mud, rain, pavement, gravel…). Come to think of it, auto rallies mimic real driving far better than paved track racing, including driving too fast for conditions, and crashing head on into trees:)
In principle, most electric motors can be generators. In practice, a motor-generator should be designed for that purpose, again possible in this case(PM motors would be ideal). Yes, you need IR and visible light for ID purposes. Thieves have taken advantage of IR-only systems by wearing caps with banks of IR LEDs under the visors, which completely blank out their faces, without spoiling their vision:)
I see stealth electric power systems for bikes as an interesting design challenge, not as a practical system. Offering such systems in the marketplace would not be illegal, but the profits would be small, and detection methods would be developed quickly.

Cheating can be stopped, but in this case, I agree that it seems to be a tempest in a teapot.

. .. . .. — ….

Gerard van Vooren April 23, 2016 11:25 AM

@Mike Barno

“Rotating weight.”

There are two things. One is unsprung weight and the second is wheel inertia. They are both quite important in motorsports whith high torque and power which means fast acceleration and deceleration (deceleration up to 1.5G in MotoGP). Sprung weight distribution also matters in motorbikes and racing cars. Motorbikes (racers) have a weight between approx 70kg and 160kg. The position of the drivers also matters, that’s why they move quickly from one side to the other in the corners. This is all AFAIK a lot less important on a spaghetti powered engine driving a 6 kg bike without springs. The acceleration is much less and cornering is quite different.

Mike Barno April 23, 2016 12:07 PM

@Gerard van Vooren,

I’m familiar with the concept of unsprung weight in auto racing, but skipped it here, both because it’s not relevant to on-road cycling and because I don’t have a physics angle to tie it into the tech discussion.

As for rotational inertia, in auto racing it’s not just wheels, but engine crankshaft, flywheel, driveshaft, axle shafts, hubs, brake disks, and so forth. Connecting it back to the thread’s original focus on tech cheating and detecting violators, one important tool for inspectors (both in NASCAR’s national series and at local short ovals) is a simple magnet. Far cheaper and more portable than MRI, X-ray, thermal imaging, ultrasound, etc., and it won’t break down in dusty pit areas. To keep costs from getting out of hand, many of these components are required to be made of steel: if a magnet won’t stick, then the part is illegal and the car is disqualified. One side benefit is elimination of super-hot, difficult-to-extinguish magnesium fires. Another is elimination of brittle carbon fiber with the difficulty of cleaning up the resulting tire-puncturing shards.

WhiskersInMenlo April 23, 2016 1:24 PM

Thermal imaging has its place in detecting magic as well.
“Double, double toil and trouble; Fire burn, and caldron bubble.”
WS Died: April 23, 1616

I am also reminded of these sensors.
Modern sensors will likely have a much lower signature than what they
intend to sense and will have rather long range compared to the
detection devices that might counter them.

For bicycle racing there are two issues to address:
Power source and motor.
It seems to me that portable X-ray would
be well capable of detecting at least one of
these two if not both. An automated X-ray
could safely live in the bed of a pick-up truck and
with motion of the X-ray generator and a fast
digital sensor and modern data processing fully
capable of 3-D imaging if not today tomorrow.

The heat detected in this could have explanations
that do not involve cheating with motors. Professional
racers do generate a lot of power and if the rear hub
or sprocket was to flex it could generate easy to detect heat.
Flex, perhaps the result of optimizing for weight or
choice of materials for strength.
Power levels here are higher than I would have guessed. WP
tells me: “Maximum power levels during one hour range from
about 250 W (“healthy men”) to 500 W (exceptional men athletes)”

The tech involved is way beyond….

The TI may be detecting a hub that is failing and not

My bias, this may be a stunt (demonstration) to sell
more instrument hardware to professional cycling clubs and controlling
bodies. Regulation changes often follow instrumentation
tech. improvements. It is seldom that regulations change
because of studies that show harm.

All that said… it is a cat and mouse game.
I will be watching for tails and other “gifts”
on the front porch.

Gerard van Vooren April 23, 2016 1:51 PM

@ Mike Barno,

It’s funny that you mention NASCAR. I always thought that NASCAR was one of the fairest motor sports simply because it’s entirely mechanical. That said, NASCAR is as alien in Europe as Formula One in the US so I could be wrong. I think you have to be careful with “bad” good ideas. There are lots of people making a living with these sports and they have thought about these problems as well. I think that easy solutions have been considered more than once.

r April 23, 2016 1:53 PM


Nice point about a failing rear end heating up, so now detection of a motor requires either physical examination (xray/dissection) or a very long IR+visible spectrum video?

A motor could even be used to simulate the resistance of a failing bearing I imagine, minus audio?

And thanks for the link to the 11 speed internals I’ve only seen 3 and 5s. 🙂

Mike Barno April 23, 2016 3:37 PM

@ Gerard V,

NASCAR was all-mechanical, even requiring carburetors until moving to electronic fuel injection a couple of years ago, as a way to keep it easier to police tech rules… but that didn’t make it cheat-free. These days team budgets are in the 8-digit (US dollar) range for the top series, Sprint Cup, which is still a lot lower than Formula One. But even back in the days when NASCAR teams were family operations run out of a garage, there were always efforts to gain advantage by cheating. Racers are like that, regardless of the purse money offered. For example, read about Smokey Yunick. ( ) He built a seven-eighths scale Chevrolet Chevelle for lower air resistance on superspeedways. He engineered hidden fuel reservoirs to go further between pit stops. He hid nitrous-oxide injection systems for higher peak power. In Indycar and drag racing as well as NASCAR, he came up with tricks that were legal only because rule makers had never considered them, such as the first wing on an Indianapolis racer for downforce to improve cornering.

pedaler April 24, 2016 12:44 AM

Re: regenerative braking.

Power levels during hard braking (which is usual during a race) are multiple kW. So not compatible with a small 50W or so motor, battery and control electronics.

OTOH using a motor/generator and battery in manner of a Prius would be an advantage. It would allow the rider to maintain a more constant power level, which is more efficient than varying it to match the tactical situation.

chris l April 25, 2016 7:22 PM

@Mike Barno – Oval track racing on bicycles does let riders bias the mass to the inside, but not in the same way as cars. On a steep track (as are the 250 m tracks used for most international competition) riders are tipped over so their wheels are perpendicular to the track in the corners, and the tracks are typically around 45 degrees. You can bias the mass high to decrease the moment of inertia slightly. The curves aren’t quite semicircles– they’re typically cycloidal so that the centripetal acceleration comes on slowly and maxes out at the middle of the turn. Sometimes the slope of the straight going into vs out of the turn is shaped slightly differently as well.

It’s very common for track cyclists to have to add mass to their bikes- track racing has the same minimum weight as road racing (6.8 kg) and the bikes have a lot fewer parts. Sometimes the mass is put into making tougher frames – I’ve seen a few high end carbon frames come out of high energy crashes barely scuffed (and seen more than a few of all materials – carbon, steel, and aluminum destroyed).

@various posters re energy density of batteries and being enough to make a difference:

You can easily stash 100 Wh worth of LiIon batteries in the tubes of a bicycle. 100 Wh is way more than enough to make the difference in a race, particularly with a long climb at the end. On the flats at high speed, speed goes as the cube root of power (due to wind resistance) and riders without motors could easily draft, negating the advantage of the motor. In fact, motorpacing is an extremely common training technique to develop speed, so most pro riders are good at it. On a climb, speed is generally linear with power (speeds are low enough that wind resistance makes little difference) so having an extra 30-50 W on a long climb means you can either ride away from a weaker rider or stay with a stronger one, and skill of the other riders can’t mitigate it (unlike on the flats).

Bumble Bee April 28, 2016 9:20 AM

I used to own a bicycle that had a little generator with a roller-type “gear” that could be flipped down to engage the rear tire. It stole some of my human-power but it generated sufficient electricity to power a headlamp with enough brightness to light the way in total darkness. Perhaps that, too, would have left a heat signature on the rear tire.

fajensen April 29, 2016 7:54 AM

Watching professional bicycle racing is like reading an Agatha Christie novel. One knows that most of the characters are up to no good, some are innocent victims and that in the end all is revealed and someone will be nailed.

The sports side of Tour de France is a side-show, the necessarily complicated stage for this years enticing Mystery Story: What crime(s) was perpetrated by WHO and HOW the foul deed(s) were done. Good stuff.

There are nice flowing pictures of medieval villages and landscape too.

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Sidebar photo of Bruce Schneier by Joe MacInnis.