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52

The simplest answer to your question is that 1) speeds have increased; but 2) speeds would have increased even more except Tour organizers have been consciously making the Tour harder in order to increase the drama, suspense, and entertainment value of the race. That makes comparisons of overall winner's speed quite complex when combined with normal ...


37

There are a few "pseudo-facts" I think might be at play in this graphic: You mentioned 10% of increase, say from 35km/h to 40km/h average speed. That is a VERY significant increase. Anyone well trained can sustain 35km/h average for some time even in a mountain bike, but FORTY km/h is MUCH HARDER to sustain, and that's because aerodynamic drag is ...


32

Speed varies widely by cyclist, depending on fitness, road conditions and traffic. Some of my observations (cruising speed based on a flat, paved road in good condition): 20km/h - many "occasional" cyclists ride around this speed 25km/h - most commuters 30km/h - fast commuters, slower roadies 35km/h - fast roadies any faster than that on a long flat and ...


28

Gabe, If you love the frame, and are willing to spend the money to keep it, start upgrading everything else. Start with: Wheels/tires - rotating mass will slow you down the most - go to aluminum wheels and thin/light tires size 23 or 25. Bottom Crank - Once again rotating mass, you can get some hollow core cranks, and adjust the chainring sizes to the ...


24

The key to understanding your situation is its unusual nature. Speed on hills is mostly determined by power-to-weight, while speed on the flat is mostly determined by power-to-aerodynamic drag. The problem is that speed in head winds is also mostly determined by power-to-aero drag, so the conundrum is why you're good in head winds but not on the flat under ...


21

This is an interesting point of view. Let's unpack this a bit. Assume I have a ride that is 10 miles of flat, 10 miles of ascent, and 10 miles of descent. On the flat I maintain a constant 20 miles/hour. On the ascent I fall back to a constant 10 miles/hour. On the descent I maintain a constant 30 miles/hour. My average speed for this would be: (10 miles ...


20

No, you will not ride faster in any meaningful way unless you're doing time trials at an elite level where mere seconds (or less) of improvement are gained through optimizing a long list of equipment (with clothing in the middle of that list). As always, the overwhelming determinant of performance is training. The real reason for wearing a jersey is the ...


20

The only thing that will make the bike have a higher top speed (on the flats) is changing the gearing. Bigger rings up front and smaller cogs in the back. Beyond that: start training. You're the engine, after all.


17

The Tour de France is primarily an endurance event, where team strategy is more important than outright speed. In addition there are UCI rules for racing bicycles. This includes a 6.8kg weight restriction that has been in place since 2000. If you want to compare outright speeds it would be more interesting to look at how the average speed of the time ...


16

I am not a bike expert, but a computer programmer. The problem with this question is that there is no control to compare it to. Each year the TDF changes. They visit different parts of Europe, yes it is not 100% in France. This means you can't compare times between years. Weather (not climate) is a concern. The temperature, wind and humidity will impact ...


16

I happen to be one of those who attract new riders into the sport, and have given the basic training to many people. Here is a brief of what I try to teach them: Riding position Be ready to react Have your bike properly tuned/fitted Scan the terrain(Look forward) Use a proper braking technique Never get to the extremes Grow progressively The most ...


14

The increased weight of the larger wheel (if indeed it does increase) will of course add weight to the bike, but additional weight adds very little rolling resistance (though it does of course affect hill climbing). It is a myth that "rotating mass slows you down". In terms of top speed there's no difference between weight on the wheel rim and weight ...


13

What really struck me though was that the average speeds really haven't changed much The chart ranges from about 25km/h to over 40km/h, and that is a big change. As others have mentioned, increasing your average speed requires a non-linear increase in power applied to the pedals. In other words, to increase average speed from 25km/h to 26km/h is easier ...


13

I think this relates quite nicely to motorbikes where you corner at very high speeds and I'll give a run-down of the techniques, why they are useful and how they apply, and how they might apply to cycling. So when turning left: You shift your weight over on the seat and tilt the bike left. This allows the centre of gravity to be slightly lower, aiding in ...


12

The following forces are acting on your bike as you roll downhill (in more or less decreasing order): Gravity The force of gravity is proportional to mass. If two riders have the same aerodynamic profile, the heavier rider will descend with a higher maximum speed. This is easily seen in the formula for terminal velocity. The intuitive explanation is that ...


11

Honestly. Get a new bike. Technology has changed greatly since the 80's bikes are much lighter, comfortable and stiffer thanks to space age technologies like carbon fiber. Can't afford it, check craigslist. That being said. If your are really attached to your bike. You will see the best performance improvement in new tires and wheels. When you accelerate ...


11

It depends. I don't know of any scientific research to support an actual speed. The main factors are the speed of the wind that you are riding in, and the size of your shield (i.e. the bunny in front who is giving you the wind break - the bigger the better) and how closely you follow. In still conditions I find that even at about 24km/hr (15mph) I will ...


11

In "Epidemiology of bicycle injuries and risk factors for serious injury" by Frederick P Rivara, Diane C Thompson, and Robert S Thompson, the authors gave a questionnaire to 3,390 bicycle riders who had attended a hospital emergency department in the Seattle area. They found that cyclists involved in a crash at a speed greater than 15 miles per hour were ...


10

This page contains a table with improvements that can be made with various aero clothing and equipment. Unfortunately the baseline is already a cycling jersey, not a standard cotton t-shirt. Given the improvements that clothing can provide though I would suggest the bike jersey would make a pretty big difference. For me, though the big improvement is in ...


10

The main thing you have to consider at speed is drag: The force F on you+bike (mass m) is: F = ma = mg sin Q - F_d - F_rr where a is your acceleration, g is the acceleration due to gravity and Q is the hill angle to the horizontal. F_d is the drag force which doesn't scale with mass. Try dropping a balloon and a (soccer) football of the same size and ...


8

It is not necessarily how fast you go, but how closely you are following the person cycling in front of you. The closer you follow, the more likely you are to trail in the wind they have helped part for you. The effects of this feel greater the faster you and the other person is traveling. The effectiveness of the slipstream is relative to the speed and ...


8

the cheapest ways to go faster are to get high pressure tires--120 or even 140 psi (sorry I don't know what that is in kBar)--and keep them at high pressure. For the highest pressure tires, this means pumping them up every time you ride. For 50 bucks (US) or so, you can't go wrong with this upgrade, because you can transfer them to a new bike if you if want ...


8

Basically whatever works. If you're trying to conserve energy it's foolish to push yourself going downhill, since energy lost per mile to wind resistance increases with the square of speed -- just take advantage of the "free ride" on a reasonably steep hill. Going uphill depends a lot on your physical condition and how steep the hill. You first need to ...


7

How long is a piece of string? Your speed is totally dependent on your surface, equipment, bike type ... and you! I keep a record of most of my training ride (for the last few years with GPS, but summary data going back further) and compete with myself. If you're interested in what you should/could be doing, maybe liaise with a local club. On my commute ...


7

Last year I plotted average speed versus race distance and there's an incredibly accurate inverse relationship. http:///www.32sixteen.com/2011/07/25/correlation-does-not-equal-causality/ But to add to my chart and flesh out the reason I think it hasn't increased so greatly. The Tour is a stage race. The average speed we have presented is the average ...


7

Note: I've included things not at the rear of the bike as sometimes we think something is coming from one area when it's actually caused by another. List of things I would check: Wheels true and round without rubber (check dishing too, but unlikely to cause vibration) Adding rubber (tire and tube) and inflating does not take wheel assembly out of true ...


7

First off, understand that the geometry of the bike affects stability, especially the "marriage" between head angle and fork rake. Adjusting these parameters (which can really only be "adjusted" by the frame builder) has a very dramatic effect on stability. Beyond that, the hand position has an effect in a couple of ways. First, if the hand position is ...


7

I'm not sure that anyone is going to be able to give you a definitive answer... especially since you are asking if your commute will improve by 30 seconds when the commute time you give has a range of 60 seconds. But 30 seconds out of 17.5 minutes is about a 2-3% improvement, which seems reasonable... The more interesting question would be "what can this ...


6

300 miles a week is extremely high mileage. Very few people can pull that off. I'm surprised that you feel you need to ask for advice. :-) That said the way the cyclists increase speed, like runners and swimmers, is to train with intervals. This means increasing your speed until you're at/near/slightly-above lactate threshold, holding it for a minute or ...


6

Qualification Your question is missing specifics such as hill grade, but let's assume you are talking about steeper grades where it is relatively easy to hit speeds above 40 mph. Second you didn't mention environmental conditions (such as cross-winds) as some positions become rather dangerous if you are hit by a cross-wind or are descending a rough road. ...



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