Acceleration rate for bikes
 

I searched the BF and came up with blanks.
Does anyone have data on Acceleration from standing still to let us say 22 MPH?

Why 22 MPH? I get unstable biking standing up at speed above that.
I used a Treck Hybrid for this today. Total weight with Treck stem mounted bag is 38#.
Tires 700 x 38.
On smooth limestone trail.
No wind.
0 to 22 MPH in 20 seconds. (I have not the slightest idea if that is good or bad) Perhaps I can do better.

You know that it is common to talk about cars accelerating from 0 to some speed, so why not for a bike?

I will test this soon with my Treck Madone. That should be interesting.
Jppe, are you there? I think you would know this kind of data.:)

Why not sit down and go faster than 22? Go for it!
Bicycle Drag Racing. Does it exist? I don't even want to imagine it.

Wow, as an Engineer, I never considered that, I'd think gear selection would be prime factor.
I think a changing gears would cause a significant delay.
I'm guesing your instability is due to Cadence? I know mine would be. I know folks who have hit 200+ (Honest - semi-pro) and in TT's I've been in I often see Fixed gears. They seem not worried to get a good run from a standing start, but I've never heard them speak of time to XX. Course all that matters is TT Lap/total time. . Also, Sprinters Never change gears once they start final sprint, but they are moving. But going from 30mph to 35/38 would not be as significant.

Good question Will. I use a 53/18 fixed, I'll give it a try.

I am experimenting with this. At this time I go in a big gear, stand up and go like hell.
Sitting down would not produce that power, I think. Shifting gears would cost time.
But as I said, I will try anything soon.

I agree with the time for shifting gears.
I use 53/16 and go like hell. No reason not to try 53/12 or 53/14. We shall see.
I am just puzzled why this is not a popular topic? We talk so much about average speed, why not drag racing?

Maybe they need quarter mile drags in the TdF :D

Richard

I think you need to find Robbie McEwen's, Alessandro Petacchi's, Thor Hushvold's, Erik Zabel's or Tom Bonnen's email address to properly answer this question. And an edit--"Fast Freddie."

If you watch the starts at the prolog or the individual time trials you may get a visual impression how fast these riders accelerate.

They do not have the best gearing for acceleration though. Notice that they use a starting ramp to assist the rider in coming up to some reasonable speed.

Quarter mile drag racing........hmmmmmmm........now that sounds like a variation of the sport that I would be interested in.................:D

Most road race sprinting comes at the end of the race w or w/o a leadout, so finding a standing start time might be tough for the guys mentioned. I think track riders are the closest as they frequently play position games going into the last lap and I have seen velodrome races where the riders are close to track standing and then going into a sprint.

I don't think I have sprinted from a stop but I frequently sprint out the last little hill on our daily ride. So far I have gotten up to 30mph with no leadout and starting from say 19mph, standing and pushing a 53/16 combo, I think cadence was somewhere around 120

I think they have a jersey for the fastest sprinter, just saying.:D

If they let a big dog loose just after you start rolling, bet the rate goes way up!!

Slightly different issue but sitting is supposed to be more efficient.

Sprinting uses fast twitch (anaerobic) muscles which us geezers
(I had to say it) have substantially lost. A technique to recover
some fast twitch by converting slow twitch is plyometrics. When
I was trying to bump ski (trying only,not succeeding) I did that
some and believed that it helped. When I spend less time in
physical therapy (shoulder injury) I intend to try again.

I can't remember any nutritional suggestions for anaerobic activity.

Are any top racers also engineers? That would be the guy to talk to!

Will, if you pedal up to 22 mph in 20 sec from a standing start, your acceleration is about 1/20 of the force of gravity. Cars typically accelerate in traffic at between 5 % (i.e. 1/20) to 30 % of gravity.

If we're talking about bicycle drag racing, I think, like a race car, you'd need to find the cadence at which you can produce the highest sustainable power, then arrange a gearset and shift mechanism to keep yourself at the peak output as the wheel and pedal speeds increase. Positioin and pedalling technique would be critical to stay stable as you say. I wonder if anyone has tried to engineer this sort of thing in the HPV world?

Or just find the best comfortable fixie gear, start in such a way that you don't hurt yr knees, and haul out.

Interesting ot see what you'll do on your road bike!

Road Fan
Systems engineer

How fast do horses go? Can a fit cyclist beat a horse?

Dunno, really, Deeg! But we engineers are great at educated guessing, so here goes:

Top riders can generate over a thousand watts (1.3 horsepower) for short duration, and Floyd I think did around 450-500 on his great climb last TdF. Horses as a standard assumption produce on the average one horsepower, around 750 watts. I'd assume race horses are at least twice as good, and by analogy could generate peak power in excess of two thousand watts.

So a Floydish rider has a peak power around 1.3 hp and a race horse around 3.2 hp. The race horse weighs perhaps 1000 pounds and Floydish with bike perhaps 200, a 5 to one ratio. Floydish would have a power to weight ratio of 154 pounds per horsepower, and the race horse around 300 pounds per horsepower.

It's surprising to me that a Landis has a definite possibility of outrunning a race horse on his bike!

I don't say he CAN outrun the horse because of the general looseness of my analysis.

Road Fan

No, but at their level of racing, they have all the top engineers with all the bike companies answering the questions for them. Then there are the teams of doctors, nutritionists, designers...........

According to a search or two, American Quarterhorses can hit nearly 50 mph at the finish line. But it's all sprint; their name says their specialty - they were bred for very short (quarter-mile) races. I've heard it said that a trained long-distance runner (human) can run a horse to death.

Funny, my wife's quarterhorse is usually going about... zero.

I assume that we are going to disallow the bike in this picture. Turns out that there are a bunch of crazy's doing this. One run they mentioned was 0 to 30 in 3 seconds.

Some of you California folks may be able to find out more about the annual Tour de Nez in Taho which is supposed to include bicycle drag racing.

There is a posting on the web by a rider who claims to have outraced a mustang 5.0 over 200 meters...........my experience says !@#$. The average high performance street car can under ideal conditions pull 1.0G for the first 100 feet and bicycles are not in that league or the next one down or the one below that.

Just for fun, think of the modern Top Fuel Dragster............its doing 100mph at the 60 foot mark..:eek:

I'm here!!

The closest thing I can compare it to from person experience is the Time Trials we do. We are clipped in and someone is holding our bikes upright so we start at zero speed. We accelerate to much faster than 22 mph...I'll have to look at some of my Motion Based dashboard stuff just to see how long it takes me.......but I'm not that fast a sprinter. I'm usually still standing above 22mph and haven't noticed any instability issues. Not sure what's going on in your case.

I even so some standing on downhills and flats for short periods to stretch on road rides at speeds that are easily above 22mph and haven't noticed an instability issues either. If it's pretty fast I might have my thighs against the frame to hold it steady if I'm not pedaling though.

Sorry can't help too much.

I will pursue this but it will be this coming Tuesday before I will be able to get to my Madone.
I verified the numbers with the Treck Hybrid today and they were correct within reasonable tolerance.

I am still puzzled that there is no hard data. Does not sound so outlandish to me.
There is much discussion of the inefficient shocks on Hybrids. What better way to measure than this way?
How about a comparative test of CF to Steel to Aluminum to Titanium frame bikes?
How about weight loss compared to rigidity of frame?

The conversion of the force of our legs into accelerating us and the bike in a measured time.
Sounds to me as if we should know that.:(

I think some track sprinters hit 40mph in 2-3 seconds from a trackstand.

Well, that would explain it. If that is true and possible it would not be easy to analize these extreeme acceleration values.
I am thinking, 40 MPH in 2-3 seconds???:eek: :( ,.............. is that not faster than most cars?
Not sure, help.

Sorry, not a stand still, I think they were rolling along at like 9-10mph, but the acceleration from there to 40+ is ridiculous.
http://www.youtube.com/watch?v=BkkTSVVrPYk

Wow. 20 seconds for a 38 pound bike to get up to speed. That is faster than some cars I have owned.