hilarious

Wow, thats very interesting :)

It should be possible to make the electric motor run silently relatively easily; the most noisy part of such a mechanism is usually the straight cut gears in the transmission. Straight cut gears are used in most electrical motor transmission systems due to them being plastic and need the whole tooth length in order to sustain the torque loading put onto them via the motor. Also cheap to manufacture.

The solution is helical gears : https://engineering.purdue.edu/~asm222/images...lical2.jpg


Road cars use these in order to reduce noise levels, as only a small proportion of the two driving teeth are in contact at one instant. They are also more inefficient due to the teeth "sliding" over each other.

The only other noises an electrical/mechanical system such as this would make is from the motor itself. The main noise source from a motor when its operating are the bearings which hold the rotor in; some high quality bearings should sort this out as well. There is also the "hum" of the motor, but this is a relatively small motor and should be negligible.

Imo, from a technical standpoint, it's very easy to make such a device run very, very quietly and not have the typical "whining" emitting from the bike. Any other small noises should be easily disguised by the background noise of the crowds etc.

As for it reaching 50 km/h, thats one of the wonders of electric motors. If your just talking about dc motors (and not three/single phase ac motors: yuck), they dont really have a power curve like an internal combustion engine. They create maximum torque at 0 rpm, and it almost does not deviate from then on, but usually does decrease due to increased friction from bearings etc. A lithium battery powerpack, a small electronic "brain", and your away.

I think its quite possible for this to be done. My 2 cents :)

Good post. Explained alot of things. I guess it would be doable like you say and the noise coming from the crowd, cars and bikes would disguise it. What about the engine wieght? The bikes they use don't differ that much in weight and my first impression is that an engine able to output 50km/h doesn't come wieghtless. Someone ought to feel the dfference.

I read a bit more about this guy and apparently he changed bike in the middle of a route. He then caught up with the leading group and just flew past them, extended his lead and won.

The video does look fishy and even though i'm not into cycling it does look odd that he's able to accelerate better while sitting down. I thought the whole idea of sprinting is to stand up to gain more power and thus more acceleration which equates into speed.

hehe funny. it's a pro sport so you never know

I mean, it probably is possible to get this kind of acceleration while sitting down. (Jan Ullrich for example)
But this looks crazy.

only downhill cos he's fat :(

All objects fall at the same rate regardless of mass, as was demonstrated with a hammer and feather on the moon.

'twas shopped m8

Lol, skip to 3:40 its fucking hilarious.

Cancellara is in full TT position - and he's a mean TTer while the other riders are soft pedalling. Definitely plausable.

why's anyone still following cycling? it should just disappear from all means of coverage and die, bunch of cheating losers.

you really are a thick cunt aren't you

Sweet! BRB winning the tour de france lulz!

While this seems perfectly possible I have no doubts about Fabian Cancellara's talents - the man is a machine and just has the perfect build for time trial style racing. It's not like he's just started winning recently. The guy has always been a monster.

Love the part on the mountain. The other guy is pedelling for his life and Cancellara seems to be relaxed, but the gap is getting huge by seconds :>