# Re story about cheating pro-bicyclist how do you hide a cheating "motor" in a racing bicycle? **URL:** \ **Category:** Factual Questions\ **Created:** [February 1, 2016, 10:40pm UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886 "2016-02-01T22:40:09Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [February 1, 2016, 10:40pm UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/1 "2016-02-01T22:40:09Z")
Per the story below (which does not have tech details) how do you put/hide a useful motor in a skinny frame racing bike? Any pics of how this is accomplished? [Cyclist withdraws from race after officials find a hidden motor in her bike](http://www.sbnation.com/lookit/2016/1/31/10879424/cyclist-withdraws-race-motor-inside-bike-hidden-oh-my-cheating) > [@](#): > > Bicycling has the best cheating. Hands down. Other sports might try to step to the champ with their deflated balls and recorded practices, but NOTHING compares to having a motor in a bike that’s supposed to be propelled by a person. Femke Van den Driessche was forced to withdraw from the under-23 race at the cyclo-cross world championships when officials made a curious discovery while inspecting her bike following mechanical problems. > > A motor was mounted inside the bike with cables and housing found under the bike’s saddle. Van den Driessche was a favorite in the race and claims she had no idea the motor was inside her bike – saying she purchased it from a friend. ---
**Author:** ![Atamasama](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atamasama/32/12961_2.png) [@Atamasama](https://boards.straightdope.com/u/Atamasama)\ **Post date:** [February 1, 2016, 10:43pm UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/2 "2016-02-01T22:43:23Z")
Double post. ---
**Author:** ![Atamasama](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/atamasama/32/12961_2.png) [@Atamasama](https://boards.straightdope.com/u/Atamasama)\ **Post date:** [February 1, 2016, 10:46pm UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/3 "2016-02-01T22:46:11Z")
> **[Hidden motors for road bikes exist -- here's how they work](https://www.cyclingtips.com/2015/04/hidden-motors-for-road-bikes-exist-heres-how-they-work/?scope=anon)** > > The UCI made headlines back in March for checking several dozen bikes for hidden motors at Milan-San Remo. Many fans laughed off the incident as a ridiculous waste of time, somewhat prematurely perhaps. Concealing a motor in the frame of a road bike... I can’t help but feel the defense from the accused is something I’ve heard hundreds of times on _Cops_. ---
**Author:** ![snowthx](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowthx/32/10660_2.png) [@snowthx](https://boards.straightdope.com/u/snowthx)\ **Post date:** [February 1, 2016, 10:57pm UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/4 "2016-02-01T22:57:06Z")
[Here is another article](http://www.businessinsider.com/bike-investigated-technological-fraud-cycling-world-championships-cyclocross-2016-1) on the incident - including some videos of said motor in action. They are calling it “mechanical doping”. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [February 1, 2016, 11:02pm UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/5 "2016-02-01T23:02:12Z")
> [@snowthx](#): > > [Here is another article](http://www.businessinsider.com/bike-investigated-technological-fraud-cycling-world-championships-cyclocross-2016-1) on the incident - including some videos of said motor in action. They are calling it “mechanical doping”. Fascinating. That is some s\*\*\*! ---
**Author:** ![Nefario](https://avatars.discourse-cdn.com/v4/letter/n/59ef9b/32.png) [@Nefario](https://boards.straightdope.com/u/Nefario)\ **Post date:** [February 2, 2016, 12:47am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/6 "2016-02-02T00:47:46Z")
Kewl! I’m surprised that a motor and batteries hidden the downtube could impart enough power to be worthwhile. Maybe it was used as a regenerative energy storage device (KERS) or “power boost” button as in F1 and Indy cars. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [February 2, 2016, 1:13am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/7 "2016-02-02T01:13:08Z")
The bike frame could store a tremendous amount of energy in it. These are races where the last once of human energy is expended. It wouldn’t take much to significantly alter a race. ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [February 2, 2016, 1:41am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/8 "2016-02-02T01:41:31Z")
> [@Nefario](#): > > Kewl! I’m surprised that a motor and batteries hidden the downtube could impart enough power to be worthwhile. Maybe it was used as a regenerative energy storage device (KERS) or “power boost” button as in F1 and Indy cars. The first video quoted 250 W output for 30 min. Ballpark figures, a reasonably fit person can sustain a ~100 W output and an elite cyclist several times more than that (300 W?) So without any regenerative braking, already that’s enough energy to provide a power boost \> 40% for races less than an hour, or ~ 5% for an 8-hour race. Wiki says there are non-rechargeable lithium batteries with a 4 MJ/L energy density, and rechargeables with 2MJ/L. For a 125 watt-hour battery that’s only 100 mL for non-rechargeable batteries, which should be trivial to pack in the frame. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 2, 2016, 1:55am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/9 "2016-02-02T01:55:19Z")
I’m pretty sure that Lance Armstrong managed to top one horsepower, which is about 750 W. Decide for yourself whether that counts as within the bounds of human ability. Even so, though, 250 W would still be a significant boost. ---
**Author:** ![gazpacho](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@gazpacho](https://boards.straightdope.com/u/gazpacho)\ **Post date:** [February 2, 2016, 2:02am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/10 "2016-02-02T02:02:33Z")
But how long could Armstrong sustain 750W? This link has estimates of his power output during various climbs in the Tour de France for a few years. The highest I see is 495. With most being mid to low 400s. > **[Tour de France 2009: Power estimates](http://sportsscientists.com/2009/07/tour-de-france-2009-power-estimates/)** > > The Tour is currently winding its way through France, in what is another pretty sedate and routine stage so far. It’s looking like a sprinter’s stage, and maybe the battle for green bet… This is another thread about this. There are some good links in there showing commercially available hidden motors for bicycles. They seem to indicate about 100W extra power for upto 90 minutes. > **[No, Really: tiny electric motors inside the bike frames of professional...](https://boards.straightdope.com/sdmb/showthread.php?t=782833)** > > It sounded so far-out at first. Then, a few years ago it starting seeming possible, and now it is confirmed. Inside the bikes of one of the top contenders at the world cyclocross championships, no less. Cookson confirms ‘technological fraud’ at... ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [February 2, 2016, 2:02am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/11 "2016-02-02T02:02:54Z")
> [@lazybratsche](#): > > The first video quoted 250 W output for 30 min. Ballpark figures, a reasonably fit person can sustain a ~100 W output and an elite cyclist several times more than that (300 W?) So without any regenerative braking, already that’s enough energy to provide a power boost \> 40% for races less than an hour, or ~ 5% for an 8-hour race. > > Wiki says there are non-rechargeable lithium batteries with a 4 MJ/L energy density, and rechargeables with 2MJ/L. For a 125 watt-hour battery that’s only 100 mL for non-rechargeable batteries, which should be trivial to pack in the frame. A pro rider can do 100 miles in roughly 3.5-3.75 hours. 27 mph is 419 W ([calculator](http://www.kreuzotter.de/english/espeed.htm)). Add 100 W gains just over 2mph, the 90 minute battery means the cheating rider will gain 3 miles in the last 1.5 hours while working no harder than the peleton. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [February 2, 2016, 2:17am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/12 "2016-02-02T02:17:38Z")
Yes a person can do a HP in a sprint… for about a minute. The HP was the minimum a horse can do, the amount that it could do without raising a sweat, and it was some sick old horse walking on a smooth wooden floor ! , so that an engineer can say that if you had 4 horses, they would surely do 4 HP … They mixed up the bikes ? The bikes were so identical … sort of makes sense…you do that as you want heaps of spare parts to get the main bike going. The friends bike may have had the motor so that she can keep up, to help with training. The description of wires up to the bike seat suggests that it was setup to have a battery hanging off the seat … Tee motor kit that you can buy has the motor in the vertical between crank and seat, and wires up to the seat… So she would have had to have a battery … eg hidden in a tool bag… She didn’t ride with any bag did she ? They could say there was no where to hide a battery couldn’t they ? The mechanical failure may be relevant… did the motor break because it was in use ? Did it simply jam the driving gear “on” … and prevent her being able to pedal or coast without pedalling ? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 2, 2016, 3:08am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/13 "2016-02-02T03:08:23Z")
**Gazpacho** , I think that those power figures are just the power expended in lifting the cyclist’s (and bike’s) weight against gravity (at least, those are about the same numbers I got when I looked up Armstrong’s speed and hill inclines a while back). But the biker is actually expending yet more power than that in overcoming various resistive forces (mostly air resistance, plus a bit of friction in the bike’s bearings and rolling resistance). If it were just a matter of gravity, then it would take no power at all to ride on a level road. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [February 2, 2016, 3:10am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/14 "2016-02-02T03:10:31Z")
> [@Isilder](#): > > Yes a person can do a HP in a sprint… for about a minute. The HP was the minimum a horse can do, the amount that it could do without raising a sweat, and it was some sick old horse walking on a smooth wooden floor ! , so that an engineer can say that if you had 4 horses, they would surely do 4 HP … > > They mixed up the bikes ? The bikes were so identical … sort of makes sense…you do that as you want heaps of spare parts to get the main bike going. > > The friends bike may have had the motor so that she can keep up, to help with training. > The description of wires up to the bike seat suggests that it was setup to have a battery hanging off the seat … Tee motor kit that you can buy has the motor in the vertical between crank and seat, and wires up to the seat… So she would have had to have a battery … eg hidden in a tool bag… She didn’t ride with any bag did she ? They could say there was no where to hide a battery couldn’t they ? > > The mechanical failure may be relevant… did the motor break because it was in use ? Did it simply jam the driving gear “on” … and prevent her being able to pedal or coast without pedalling ? The rider would notice a weight difference. ---
**Author:** ![Little\_Nemo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/little_nemo/32/3120_2.png) [@Little\_Nemo](https://boards.straightdope.com/u/Little_Nemo)\ **Post date:** [February 2, 2016, 3:33am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/15 "2016-02-02T03:33:16Z")
> [@Isilder](#): > > They mixed up the bikes ? The bikes were so identical … sort of makes sense…you do that as you want heaps of spare parts to get the main bike going. > > The friends bike may have had the motor so that she can keep up, to help with training. No, sorry, her excuse was pathetic. When you’re got that red-handed, don’t try to invent an explanation on the spur of the moment. You’ll fail. Either admit your guilt or just say nothing. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [February 2, 2016, 3:35am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/16 "2016-02-02T03:35:53Z")
> [@Isilder](#): > > They mixed up the bikes ? The bikes were so identical … sort of makes sense…you do that as you want heaps of spare parts to get the main bike going. > > The friends bike may have had the motor so that she can keep up, to help with training. And why would the totally legit friend’s bike have a _hidden_ motor and battery, if that were the case? ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [February 2, 2016, 3:48am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/17 "2016-02-02T03:48:02Z")
> [@friedo](#): > > And why would the totally legit friend’s bike have a _hidden_ motor and battery, if that were the case? Oh you know… just for the lulz. ---
**Author:** ![running\_coach](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/running_coach/32/15836_2.png) [@running\_coach](https://boards.straightdope.com/u/running_coach)\ **Post date:** [February 2, 2016, 4:18am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/18 "2016-02-02T04:18:21Z")
> [@friedo](#): > > And why would the totally legit friend’s bike have a _hidden_ motor and battery, if that were the case? Actually, if the friend is a training partner, it would allow her to apply more pressure on her friend even if she’s not quite the same caliber cyclist. ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [February 2, 2016, 4:22am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/19 "2016-02-02T04:22:24Z")
> [@Magiver](#): > > The rider would notice a weight difference. Almost certainly - it’s an understatement to say that serious riders are highly sensitive to the weight of their equipment. ---
**Author:** ![Dag\_Otto](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@Dag\_Otto](https://boards.straightdope.com/u/Dag_Otto)\ **Post date:** [February 2, 2016, 4:58am UTC](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886/20 "2016-02-02T04:58:43Z")
> [@Xema](#): > > Almost certainly - it’s an understatement to say that serious riders are highly sensitive to the weight of their equipment. A rider may not notice a small weight difference right away. But any racing cyclist would notice that the bike fit was off immediately. Saddle height would be the first thing a rider would notice, but differences in stem length, handlebar and brake hood position, saddle tilt and/or setback would all be noticeable on the first lap, if not while riding to the start line. The “it was a friend’s bike” excuse is pure bullshit. [Next page](https://boards.straightdope.com/t/re-story-about-cheating-pro-bicyclist-how-do-you-hide-a-cheating-motor-in-a-racing-bicycle/744886.md?page=2)