Ryders crash -motor?

[proffate]

Under UCI current bike weight rules a 3 lb motor and battery should not be too much on a 12 lb bike. We have the technology and we have those willing to cheat. If it isn't happening yet, it's probably because it seems over the top or unmanly, even for the dopers. Sticking in a needle may be viewed as a necessity or a right of passage into the pro ranks, but using a motor, taking a shortcut, or jumping on a train is something that an amateur triathlete would do. Not cool.

I feel like amateur triathletes would be more likely to get hit by a train than jump on one.

I have no idea how this thread is still going on given that the guy's cranks weren't moving. You think the motor is inside the rear hub?? that would be a neat trick, given that I've never seen a hub motor smaller than a dinner plate.

 

[Kicker661]

I've done a bit of googling around to look at various hobby motors, and the like. Intuitively, I am inclined to think that a hub motor could be built without *too* much difficulty that is able to provide ~20W power. IE, a useful amount, but not a MAJOR difference maker, once you account for the extra weight of all the equipment. However, this is really just speculation on my part. One big obstacle to a hub motor is power supply, as I cannot think of a reliable way to provide power to a racing style road bike hub that would not be immediately obvious.

I have done a fair bit of RC car stuff with a fair whack of power/speed to boot and i have even had a massive 15kg electric car I had 26 cars in my garage at one point all ranging in size, type and power.


I ran a 15kg electric RC truck with a 2000kv motor on 6S 22.2v, 15min run time and 60km/h top speed. The motors will put out around 3000w give or take and this thing friggin hammered from a standing start! If the car was still and you held on when i went full throttle it would rip out of your hand.

The motor is slightly bigger than the standard rear hub (motor is 40mm x 70mm) which defeats the purpose of the exercise but shows that smaller motors can move heavy weights and more importantly accelerate them bloody quickly!

The next level down in size is the 3500kv which most run on 3S 11.1v. I had a 2kg car with this motor and when on 3S and tall enough gearing it was 100km/h. Utterly insane. This motor is 'just' small enough in diameter to fit inside a hub.

Moving down again you are at the 5700kv and 6900kv motors which you run on 2S or if you are insane 3S. The guys on youtube who are hitting 150km/h with their cars are using these motors on 3S. They are one trick pony cars, high speed runs then a long cooldown because the heat buildup is crazy.
Diameter on these motors are around 35mm x 50mm or so.

If you went for a 10000kv motor they are something like 35mm x 30mm in measurement and off their guts on a 2S lipo which can be tiny.


The advantage of the bigger kv motors (like on the electric bikes) is you have more torque from a standstill plus you can up voltage and get longer runtimes which is what people want in an e-bike.

In a race the torque from a standing start isn't relevant nor is it really what you need as you would put in an attack yourself which creates to the torque to get you from 20km/h to 35km/h. Then you hit the motor that provides assisting watts to hold you at 35km/h. You don't need to go faster you only need to hold where you are which is watts/power not torque so it then becomes a question of heat and lifespan which is why it's used for bursts/attacks only.


I know people bash the whole idea but walk into the RC nerd scene and the motor/power/amps/volts/watts has been discussed to minute detail. It's like you guys discussing blood tests.

Given $400k/yr to a doctor seems normal if you gave $100k to a talented Engineer there is no doubt in my mind he would make it fit. The problem for the doubters is you guys keep thinking of chunky e-bike motors but they aren't required because you don't need the torque. Therefore very small, high rpm motors will suffice.

 

[Dear Wiggo]

Given $400k/yr to a doctor seems normal if you gave $100k to a talented Engineer there is no doubt in my mind he would make it fit. The problem for the doubters is you guys keep thinking of chunky e-bike motors but they aren't required because you don't need the torque. Therefore very small, high rpm motors will suffice.

Great post.

 

[M Sport]

I'm picking anyone that thinks you can fit an electric motor, battery and wireless unit inside a rear hub or freehub has never actually taken one apart?

C'mon guys, the moment you can see the pedals weren't turning it was a given there was no motor. At least the motor in the seat tube of Fabian's bike was plausible.

 

[nomapnocompass]

I'm picking anyone that thinks you can fit an electric motor, battery and wireless unit inside a rear hub or freehub has never actually taken one apart?

C'mon guys, the moment you can see the pedals weren't turning it was a given there was no motor. At least the motor in the seat tube of Fabian's bike was plausible.

Great post.

 

[Benotti69]

20 years ago if some told you, you could have a computer the size of a postcard and as thin as a slice of bread and more powerful than the latest computer(20 year ago) people would laugh........

Why not for motors?

 

[Catwhoorg]

Motors are feasible no question. I don't believe Ryder had one but its certainly in the realm of possibility.

Batteries, specifically the energy density attainable by the best technologies, is the limit.

 

[GoodTimes]

I have done a fair bit of RC car stuff with a fair whack of power/speed to boot and i have even had a massive 15kg electric car I had 26 cars in my garage at one point all ranging in size, type and power.


I ran a 15kg electric RC truck with a 2000kv motor on 6S 22.2v, 15min run time and 60km/h top speed. The motors will put out around 3000w give or take and this thing friggin hammered from a standing start! If the car was still and you held on when i went full throttle it would rip out of your hand.

The motor is slightly bigger than the standard rear hub (motor is 40mm x 70mm) which defeats the purpose of the exercise but shows that smaller motors can move heavy weights and more importantly accelerate them bloody quickly!

The next level down in size is the 3500kv which most run on 3S 11.1v. I had a 2kg car with this motor and when on 3S and tall enough gearing it was 100km/h. Utterly insane. This motor is 'just' small enough in diameter to fit inside a hub.

Moving down again you are at the 5700kv and 6900kv motors which you run on 2S or if you are insane 3S. The guys on youtube who are hitting 150km/h with their cars are using these motors on 3S. They are one trick pony cars, high speed runs then a long cooldown because the heat buildup is crazy.
Diameter on these motors are around 35mm x 50mm or so.

If you went for a 10000kv motor they are something like 35mm x 30mm in measurement and off their guts on a 2S lipo which can be tiny.


The advantage of the bigger kv motors (like on the electric bikes) is you have more torque from a standstill plus you can up voltage and get longer runtimes which is what people want in an e-bike.

In a race the torque from a standing start isn't relevant nor is it really what you need as you would put in an attack yourself which creates to the torque to get you from 20km/h to 35km/h. Then you hit the motor that provides assisting watts to hold you at 35km/h. You don't need to go faster you only need to hold where you are which is watts/power not torque so it then becomes a question of heat and lifespan which is why it's used for bursts/attacks only.


I know people bash the whole idea but walk into the RC nerd scene and the motor/power/amps/volts/watts has been discussed to minute detail. It's like you guys discussing blood tests.

Given $400k/yr to a doctor seems normal if you gave $100k to a talented Engineer there is no doubt in my mind he would make it fit. The problem for the doubters is you guys keep thinking of chunky e-bike motors but they aren't required because you don't need the torque. Therefore very small, high rpm motors will suffice.

great post. Inspired me to play with a few numbers.

Suppose you wanted a significant advantage from a motor. I think 25W would be enough to make a difference. To put it in perspective, an extra 25W would be the difference between about 6 W/kg, and 6.4 W/kg in the average sized racer. From the specific power calculations that I've seen, this sounds like the difference between missing the podium, and winning the race.

Suppose you only needed it in the business end of the race. I think a 1 hr duration would be enough to make a difference.

Suppose the above motor could be constructed to fit in the space envelope of the rear (or front?) hub. I am not a motor guy, but it sounds plausible to me.

Suppose this motor weighed .3 kg. If anything, this sounds generous, and I suspect it could be done with less mass.

From what I've read recently, some people think the above sounds reasonable, but think you would be devastated by the weight or size of batteries. Is that true? Let's have a look:

How heavy, and how big, would the battery be to power the above motor?

Suppose the efficiency of the motor is 75%. Suppose the efficiency of the battery is also 75%.

Target Power (P): 25 W
Target Duration (t): 1 hr = 3600s
Efficiency Motor (n_m): .75
Efficiency Battery (n_b): .75
Required Energy (E):
E = P * t / n_m * n_b
E = (25 W / 1 000 000 W / MW) * 3600 s / .75 * .75
E = 0.16 MJ

So, with 0.16 MJ of Energy, we can power our proposed motor for a sufficient amount of time.


From wikipedia (http://en.wikipedia.org/wiki/Energy_density) a lithium battery has the highest specific energy of any readily available, and practical, battery chemistry. In particular, the numbers are as follows:
Lithium Battery Specific Energy: 1.8 MJ/kg
Lithium Battery Energy Density: 4.32 MJ/L

So,
mass battery (m_b):
m_b = 0.16 MJ / 1.8 MJ / kg
m_b = 0.09 kg

volume battery (V_b):
V_b = 0.16 MJ / 4.32 MJ / L
V_b = 0.037 L

To put that into context, the battery would weigh about 90 g, and take up approximately 40 mL of space, or (allowing for a bit of packaging, etc) about 4 cm3. Much too large to fit inside a hub, but why would you want to put it in the hub anyway? Easily would fit in down tube, among other places.

The weight of our proposed system is only 90 + 300 ~ 400 g. We can round up to half a kg....

 

[sniper]

Great post.

i second that.

20 years ago if some told you, you could have a computer the size of a postcard and as thin as a slice of bread and more powerful than the latest computer(20 year ago) people would laugh........

Why not for motors?

and this.

 

[GoodTimes]

great post. Inspired me to play with a few numbers.

Suppose you wanted a significant advantage from a motor. I think 25W would be enough to make a difference. To put it in perspective, an extra 25W would be the difference between about 6 W/kg, and 6.4 W/kg in the average sized racer. From the specific power calculations that I've seen, this sounds like the difference between missing the podium, and winning the race.

Suppose you only needed it in the business end of the race. I think a 1 hr duration would be enough to make a difference.

Suppose the above motor could be constructed to fit in the space envelope of the rear (or front?) hub. I am not a motor guy, but it sounds plausible to me.

Suppose this motor weighed .3 kg. If anything, this sounds generous, and I suspect it could be done with less mass.

From what I've read recently, some people think the above sounds reasonable, but think you would be devastated by the weight or size of batteries. Is that true? Let's have a look:

How heavy, and how big, would the battery be to power the above motor?

Suppose the efficiency of the motor is 75%. Suppose the efficiency of the battery is also 75%.

Target Power (P): 25 W
Target Duration (t): 1 hr = 3600s
Efficiency Motor (n_m): .75
Efficiency Battery (n_b): .75
Required Energy (E):
E = P * t / n_m * n_b
E = (25 W / 1 000 000 W / MW) * 3600 s / .75 * .75
E = 0.16 MJ

So, with 0.16 MJ of Energy, we can power our proposed motor for a sufficient amount of time.


From wikipedia (http://en.wikipedia.org/wiki/Energy_density) a lithium battery has the highest specific energy of any readily available, and practical, battery chemistry. In particular, the numbers are as follows:
Lithium Battery Specific Energy: 1.8 MJ/kg
Lithium Battery Energy Density: 4.32 MJ/L

So,
mass battery (m_b):
m_b = 0.16 MJ / 1.8 MJ / kg
m_b = 0.09 kg

volume battery (V_b):
V_b = 0.16 MJ / 4.32 MJ / L
V_b = 0.037 L

To put that into context, the battery would weigh about 90 g, and take up approximately 40 mL of space, or (allowing for a bit of packaging, etc) about 4 cm3. Much too large to fit inside a hub, but why would you want to put it in the hub anyway? Easily would fit in down tube, among other places.

The weight of our proposed system is only 90 + 300 ~ 400 g. We can round up to half a kg....

Take it a step further. Suppose you wanted to run the motor for the entire, 6 hr race. Multiply above numbers by 6:

Battery Mass ~ .5 kg
Battery size ~ 6 cm3

If 6 cm3 sounds like a lot, consider the size of a bike seat post. Most seat posts have a diameter of ~ 28 mm. IE a a radius of 28 mm / 2*10 mm / cm = 1.4 cm. So, a surface area of pi*1.4^2 ~ 6 cm^2.

Therefore, the proposed 6 cm^3 battery would fit in a puck the size of a seat post shape 1 cm long.

 

[GoodTimes]

Take it a step further. Suppose you wanted to run the motor for the entire, 6 hr race. Multiply above numbers by 6:

Battery Mass ~ .5 kg
Battery size ~ 6 cm3

... Let's see how you conspiracy theorists, skeptics, and pro-motor crowd react now... I bet you don't hate math now that the math and science is on your side!

 

[GoodTimes]

... Let's see how you conspiracy theorists, skeptics, and pro-motor crowd react now... I bet you don't hate math now that the math and science is on your side!

Great post hog!







Ok, how'd I do on the quoting myself front?

 

[the sceptic]

Great post hog!







Ok, how'd I do on the quoting myself front?

Good posts, good times.

Here is an example of your motor in action.

http://www.youtube.com/watch?v=52xv2Hg2fkI

 

[GoodTimes]

Good posts, good times.

Here is an example of your motor in action.

http://www.youtube.com/watch?v=52xv2Hg2fkI

Well I 100% expected that link to be a repeat of the Ryder crash incident. Which would have been very funny on your part.

Watching froome again, I am wondering why does he pedal so quickly? Hmmmmmm lets thikn..... small motor in BB, low torque, needs high RPM to obtain reasonable power output????? Must be! I guess this proves it -- Froome uses a BB motor, and his high RPM attacks are to maximize the efficiency and power of the motor.

Which makes perfect sense, since most on here think Froome uses Blood Bags. BB motor to boost BB effectiveness. You all may believe in miracles.... but I don't believe in coincidences that good. You heard it hear first.

 

[Master50]

20 years ago if some told you, you could have a computer the size of a postcard and as thin as a slice of bread and more powerful than the latest computer(20 year ago) people would laugh........

Why not for motors?

There are motors small enough you need a magnifier to see them and certainly the motors in power tools are small enough to be useful in a bike How much power you get is a factor of magnetic reactions. Rare earth magnets made huge improvements in small motors but to get the power out of a motor the size still matters.

Much of the conversation is around a motor of maybe 250 watts. As has been said a motor that size is hard to hide and requires a fair sized battery to give 1 hour of power. These commercial systems are way too much for something intended to be secret. As outlined in a couple of posts a 25 to 50 watt motor would be more than enough to give a pro a distinct advantage yet much easier to conceal, maybe in a regular sized hub rather than one large enough for a power tap. You could hide a lot in one of those hubs.

So your cell phone is a super computer of the 70s but 1/4 hp motors are about the same size unless it is a rare earth magnet type and most of these are made for tools and models but they are not reduced in size like transistors have.

 

[Oldman]

C'mon dude, are you suggesting that you haven't committed to memory the previous 63 pages?

No one is suggesting that he was "motoring" downhill. It was only ever suggested that such a device may have been activated upon impact.

But we've moved on since then. Join us as we travel to the future. The cheats of tomorrow will be exposed today.

I'm seriously living in the present and totally acknowledge the existence of these devices. I've got drones for our construction projects and marvel at the power.
But a device "activating on impact" is as convenient as the rest of the posit. I've seriously seen bikes do the exact same thing with a good pedal stroke "on impact" and the right balance of the bike on a pedal. Not that mysterious...or ridiculous.
As for believing that someone would try to use it...no problem but it would involve a team or manufacturer rather than an individual rider's initiative. What bonehead would jeopardize a major sponsor or product line attempting this crap?

 

[Fatclimber]

...
What bonehead would jeopardize a major sponsor or product line attempting this crap?

I never cease to be amazed at the magnitude and quantity of "boneheads" in the cycling world that wouldn't even blink an eye at injecting/extracting blood/chemicals in their bodies. You think this particular risk is enough to deter anybody from being competitive? Not me, not in the least.

 

[9000ft]

The clinic never fails to provide great entertainment.

 

[Benotti69]

.......... What bonehead would jeopardize a major sponsor or product line attempting this crap?

I bet Festina hate cycling and will never come back to the sport after getting shat on from a height in 1998....

 

[Granville57]

I'm seriously living in the present and totally acknowledge the existence of these devices. I've got drones for our construction projects and marvel at the power.
But a device "activating on impact" is as convenient as the rest of the posit. I've seriously seen bikes do the exact same thing with a good pedal stroke "on impact" and the right balance of the bike on a pedal. Not that mysterious...or ridiculous.
As for believing that someone would try to use it...no problem but it would involve a team or manufacturer rather than an individual rider's initiative. What bonehead would jeopardize a major sponsor or product line attempting this crap?

OK, to be a bit more serious myself for the moment, by "activating on impact" all we're really talking about is something "turning on" when a force is applied. I've had kitchen appliances turn on unintentionally, as I'm sure most people have at one time or another. That's all that means.

As for the "jeopardizing a major sponsor" etc., seriously, please read back through this thread. I have made these same arguments myself.

What started out as an amusing video, has led us down the path of scientific inquiry and exploring the possibilities of what might exist now or could exist in the near future.

That is what is currently breathing life into this thread.

 

[Granville57]

Great post hog!

Ok, how'd I do on the quoting myself front?

Outstanding.

You've been assimilated. There is now no escape from The Clinic. Resistance is futile.

 

[sniper]

...
Watching froome again, I am wondering why does he pedal so quickly? Hmmmmmm lets thikn..... small motor in BB, low torque, needs high RPM to obtain reasonable power output????? Must be! I guess this proves it -- Froome uses a BB motor, and his high RPM attacks are to maximize the efficiency and power of the motor.

most intriguing hypothesis.

 

[D-Queued]

20 years ago if some told you, you could have a computer the size of a postcard and as thin as a slice of bread and more powerful than the latest computer(20 year ago) people would laugh........

Why not for motors?

They would only laugh because of their ignorance.

Transistor packing density in semiconductors was, and is, incredibly inefficient (e.g. subject to the constraints of photolithography). This is why Moore's Law remains valid.

Electrochemical reactions, motor windings, etc., suffer from the limitations of basic physics (e.g. atomic electrochemical potential).

It is ignorant to compare the semiconductor industry and its progress with electrochemical appliances like batteries (and motors and photovoltaics and fuel cells, etc.).

....

Batteries, specifically the energy density attainable by the best technologies, is the limit.

Cheers.

...

The weight of our proposed system is only 90 + 300 ~ 400 g. We can round up to half a kg....

In your dreams, but not in reality.

If you can pack that kind of energy density your invention will provide you with a multi-million dollar opportunity, and probably much more. And, it won't be the three-week grand tour, bicycle cheating market that comes calling.

Dave.

 

[Oldman]

OK, to be a bit more serious myself for the moment, by "activating on impact" all we're really talking about is something "turning on" when a force is applied. I've had kitchen appliances turn on unintentionally, as I'm sure most people have at one time or another. That's all that means.

As for the "jeopardizing a major sponsor" etc., seriously, please read back through this thread. I have made these same arguments myself.

What started out as an amusing video, has led us down the path of scientific inquiry and exploring the possibilities of what might exist now or could exist in the near future.

That is what is currently breathing life into this thread.

I can agree on that breath of life since it is surely a possibility. I chased a guy uphill on a City bike for 2km before I noticed he wasn't pedaling because his battery assembly wasn't visible.
In this specific instance it seems laughable that Garmin would jeopardize the overall sponsorship attempting something like this. That an individual rider could accomplish it without his team's knowledge is also laughable because it's all visible to the mechanics and eventually the world.
Doping is done behind closed doors and unless you ride with exposed cotton swabs at the point of injection (let's see...who did that?) no one but the person in the room can confirm it actually occurred.
An actual working version of a mini-motor like this would be hugely marketable as well.

 

[GoodTimes]

In your dreams, but not in reality.

If you can pack that kind of energy density your invention will provide you with a multi-million dollar opportunity, and probably much more. And, it won't be the three-week grand tour, bicycle cheating market that comes calling.

Dave.

Hello, thanks for your input.

I provided my source, which was wikipedia. Admittidly not the most academic of places for information, but indeed, not something I dreamed up. Instead of pejoratives, do you care to tell us what you think the specific energy of a lithium ion battery is? Do you have a source for that? Do you care to refute any of the calculations that I offered?

I've done a bit more digging. Here is a link from an open access presentation at MIT.

http://web.mit.edu/2.009/www/resources/mediaAndArticles/batteriesPrimer.pdf

Slide 5 gives a value of 150 Wh/kg. This is converted to the units that I used, MJ/kg as follows:

1 Wh : 3.6 kJ
So,
150 Wh = 0.540 MJ, or about 1/3 of the value that I used in my calculations. Therefore, for the 1 hr motor, you would have a mass of ~ 300g battery.

Now, this uses the most conservative numbers available, and does not mention the exact battery chemistry. It is well known that a lithium ion battery depends on the material used in the anode. From the wiki article on lithium batteries, the specific energy ranges from ~ 240 Wh/kg to 700 Wh/kg. I don't have time to dig further into this now, but suffice to say that I don't expect a nobel prize for creating the type of battery that is being described here.

Further, I freely admit that I have not worked with lithium batteries before, nor done the requisite background reading to fully understand lithium battery characteristics, with regards to discharge rate, heat dissipation for a larger battery, or other constraints of this nature. If you can provide a refutation of my work, I'm open to considering it. I have worked extensively with Lead-Acid batteries, which have VERY different characteristics to Lithium - Ion.