Road Cycling - Takeoff: Bicycle vs. Car

I don't know if it's just my imagination, but I have noticed that usually when I take off at a stop light, the cars are lagging way behind for the first few seconds.

There are only two reasons that I can think of:
1) The drivers are not paying attention to the stop light

2) The bicycle is far more energy efficient than the car, and therefor is not requiring anything close to the amoount of energy that the car is to accelerate

Any ideas???

the car is REALLY heavy, and even if it has more power to push it around, it would require an INCREDIBLE amount of force to accelerate it faster than a bike.

2600 lbs vs 20 lbs.... that's a HUGE difference in inertial mass. Remember the MASS of an object is a measure of an object's inertia - its inherent resistance to changes in motion

ok think of it this way: a plane can outrun a car, but a car will outaccelerate it up to say 60mph.

a car can outrun a bike, but a bike will outaccelerate it up to say 10mph

a bike can outrun a runner, but a runner will outaccelerate it for a couple feet.

Thx for the info. That's exactly what I was thinking. I was just wanting to verify it

A couple of years ago I beat a guy in a Ferrari off the line. As he pulled past me he ground the gears. :rolleyes: It entirely spoiled the moment for me.

Throttle lag, inattention to the light, and the mistaken assumption that the guy/gal on the bike is easy prey when the light changes :)

I like to stop about a bike-length behind the stop line. This has two positive effects: I can roll and clip in when I see the light's ready to change, and by the time the motorist in the next lane is aware that he/she's being outaccelerated, I'm already to the middle of the intersection because I began my roll-out from behind their field of view.

I guess I'll add torque to the bicycle's advantages. At low RPMs, a cyclist can generate tremendous torque on the cranks.

The other thing is frequently the car will hesitate until it's clear what the cyclist is doing. Like staying straight in the lane or moving over slightly. I do something similar when driving as well.

I've got 4 small marks on my car (yes I'm that anal) and I don't want a wobbly cyclist putting #5 or more on the fender.

When a light turns green, a driver has to move his/her foot off the brake onto the accerator and press down. A cyclist just has to hammer down and go, elimating about 4/10s of a second of lag. It is a bit more complicated then that, as a car has more moving parts to get moving then a bike does.

What are you all talking about???
That's false believe. Maybe you can outrun a car by half a foot. And it would only happen is the driver is sleeppy...

Get real. Bicycle has other benefits...

Originally posted by Inoplanetyanin
What are you all talking about???
That's false believe. Maybe you can outrun a car by half a foot. And it would only happen is the driver is sleeppy...

I outrun cars by much more than that on my ride home from work each evening.

The bike is supposedly the most efficient thing on earth! It translates energy into speed the best, got it in some physics textbook. It is even more efficient than walking or the space shuttle.

As for acceleration, definitely the bike wins the car. I have always won them and overtaking them is no big problem. The only time when accelerating is a problem is when I'm still in the 53-12 combination. I remember going downhill in that, stopping at the traffic light without changing to a lighter gear. It was tough to get the bike going, but soon it will start moving. so

What to race.I'll beat any bike to 10 mph.What are you guys talking about.

As for acceleration, definitely the bike wins the car

That is such an overgeneralized statement. How bout someone go out and measure what they run the first 60ft in. Your 60ft time is a common term used in dragracing. I can tell your average car will prolly be around 2.5 seconds. A 14 second quarter mile car will be around 2-2.5 seconds. Below that and you are talking sub 2 second 60ft times with daily driven street cars dipping into the 1.5 second range.

A motorist who's ready to jump, and willing to do what it takes, will be very hard to beat. Engine at 5000rpm, 2mph roll-start, dump the clutch, it's outta there. But how many motorists do that, particularly if they're only expecting a tepid, wobbly start from that geek in the lycra? :) In city traffic, they've only got a limited speed window before they've lost their shot at passing and cutting me off, unless they just want to disregard the speed limit altogether.

I remember one launch I did at a four-lane stoplight. My lane ended after about a block and there was a vehicle behind me. I was on the Fuji Team with the Zipp 440's :D and I launched so hard that the vehicle behind me was able to pull in AHEAD of the car that had been on my left at the light. I think I pulled right out to 35mph before I cut back to a cruising effort. Mind you, that's with downtube shifters. :D I had the art of knee-induced rear upshifts pretty well practiced, although I occasionally cut my knee by hitting the barrel of the shifter instead of the lever. I sure miss that bike... :(

Justin, but we're not talking about racing a car. There is no need to talk about e.t. time.

Of course if a driver really wanted to race a cyclist, the driver will always win. Any automatic transmission car can be easily launched by apply the brakes with the left foot and flooring the gas with the right foot. When the light turns green, lift the left foot off the brake and you'll be flying.

But this is not the point, I can be wrong, but I think the point a lot of people were trying to make was that, if at a stop light, when a normal accelerating car and a normal accelerating cyclist would take off, the cyclist would be ahead of the car for the first few feet.

I'm not a scientist, so I can't explain the theory behind it, but from my personal experience, the cyclist always out accelerates the car for the first few feet.

Originally posted by Chris L
I outrun cars by much more than that on my ride home from work each evening.

The car is either not racing with you, or the car has damaged engine....

Originally posted by shokhead
What to race.I'll beat any bike to 10 mph.What are you guys talking about.

Man, this guys are too much into biking. They forget or refuse to accept reality...
Let them think that bicycle accelerates faster than a car...
They will never see this happening, but at least they read it on the internet...

Great fun to beat cars off the line, even if it is only for two metres (gee, some people really want to take the fun out things, don't they?).

It comes back to a cyclist being in tune with the surroundings. Being aware of what is happening with the changing sequence in lights, working out how long they have to recover from that last anaerobic effort, having the pedal in the best position for a big push down, and getting away in one motion (including clipping in the other pedal). Plus, if you have taken the lane, it's nice to catch the driver directly *behind* off-guard as well, just when they were going to lay on the horn.

The drivers stopped at the lights are most likely listening to the radio/ CD music/ chat show, thinking about the next business appointment, what to buy at the market, that neat looking chic/guy across the road... thinking about everything but driving. They also need the rest time at traffic lights from the pressures of all that driving. Then they complain about being held up on the next block by a cyclist ;)

CADD,
The whole basis of this discussion is flawed to begin with. We get general statements saying 'I can beat cars off the line'. There are too many variables to deal with here. Is the car even trying to beat you? Are you trying to beat the car? Did the car intentionally lag off the red light as a safety precaution(ie. another driver running red lights).

The point of the 60ft times was to bring perspective into this argument and to show what average cars you see on the street are CAPABLE of.

I ride my road as well as mountain bike at least 5 days a week. I race my car at the strip and autocross at least once a month. I know very damn well that I can't even come close to out accelerating my car on my bike. WAKE up people.

Look at this clip of my car spinning tires and think again.
(Note, this is only a four cyclinder...)

http://www.angelfire.com/al2/misha18male5/images/go.mpg

REALITY CHECK!

There is no chance on earth that any cyclist could beat a car in acceleration from a standing start, in a one on one contest.
Have a look at track cyclists. They take the best part of 200 metres to reach 60kph. Virtually any car will reach that speed within 50 metres.
Crikey, my 1.5ltr Daewoo would beat Lance in a standing start competition.

Sure, I have gotten to the other side of the lights before cars, but I am the only one trying, the driver is in La La land most of the time, changing CD's or yapping on their phones.

CHEERS.

Mark

my, what an inane discussion this is...

Originally posted by Inoplanetyanin
The car is either not racing with you, or the car has damaged engine....

Or is simply not as efficient in traffic as I am. All those people I passed on the Sundale Bridge 45 minutes ago are probably still there.


Originally posted by OneTinSloth
my, what an inane discussion this is...

So why read it?

Originally posted by OneTinSloth
my, what an inane discussion this is...


Nah, you're wrong. It's good fun. Try another forum perhaps?

My car wont spin the tires,its a new morden thing called traction control and we we were not talking about being in traffic and such.Car vs bike on a clear street.Thats the last time the bike sees the car.0-60 in 7.0sec.LA cant even do that.