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bicycling suddenly a British speciality?!

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IainB:
If cycling on roads, which can make for quite fast progress, there are two drag effects worth considering:

* (a) Air drag (friction): on the forward-facing surfaces of of the cyclist's body. Many cyclists do not appreciate how much energy they have to expend pedalling to overcome air drag. The drag effect is more noticeable the faster one goes. That drag can be significantly reduced by fitting (say) the drop-handlebars of a road bike. The trouble with drop bars is that the handbrake levers are lower also. I tend to find that long periods in the crouched position for drop bars are tiring and restrictive and can hurt my wrists a bit. Thus, at lower speeds, I like to ride my road bike sitting up more straight and with my hands gripping the top (straight) part of the handlebar - which is risky as the brakes are too far away to get hold of in a hurry. So I have an ancillary pair of handbrakes fitted on the top part of the handlebar, angled down and just right ergonomically, positioned right within reach of my extended fingers when my hands are on the upper part of the handlebar - very comfortable.


* (b) Rolling resistance (friction): on the tyres as they touch the road. Many cyclists do not appreciate how much energy they have to expend pedalling to overcome rolling resistance. This drag can be considerably reduced/minimised by fitting the smoother road tyres (i.e., not the knobbly multi-terrain type tyres) - which is what I usually do for my daughter's bike. Keeping them at max pressure also helps to minimise rolling resistance.

Reduced drag can equate variously to:

* greater efficiency (less energy used),
* better energy reserves, improving the potential ability to cover greater distances,
* higher average speeds,
* a more enjoyable ride,
* a less tiring ride,
* improved motivation to cycle because one's ability to cover greater distances in a more relaxed fashion is enhanced.
The last point (motivation) in the list could be significant - e.g., when taking on the challenge of longish bike-rides, the challenge is reduced. Motivation and enjoyability could also provide mutually reinforcing feedback.

IainB:
@Shades:
I think I understand most of the points you make above, but am confuzzled where you say:
But if you cross your arms in front of your torso and bring your torso down towards the curved handlebar, so that your hands have good grip on the straight part of the curved handlebar, the aerodynamic efficiency is almost equal to that of a mountain bike, there is no strain on any injured elbow or wrist and you still have the advantages of the city bike model.
-Shades (July 23, 2017, 12:09 PM)
--- End quote ---
- "cross your arms in front of your torso"? How does that work?    :tellme:

Also, "afflicted by mountain bikes"?  Did you intend to mean "think they need to use" or were you being sarcastic? Sounds like mountain bikes are the only option (no choice) in Paraguay.
The gearing (gear ratios) of bikes is generally optimised for the kind of terrain the bike is intended for use on. The gearing of mountain bikes is thus all wrong for road use anyway - less efficient and more energy-draining. I always shake my head in wonderment when I see people on mountain or off-road bikes pedalling furiously along a road/pavement but actually moving rather slowly and not realising the implications. Ergonomics is all-important. A badly-designed bike - or one with the wrong gear ratios or that is the wrong size for the individual using it - can be very inefficient in use, and may even cause injury - e.g., kneecap damage, leading to patellofemoral arthritis

A well-designed bike efficiently converts and optimises the energy of muscle power into forward motion. Trick bikes, for example, might be great for bike tricks, but have shallow depth frames where the length of the fully-extended leg is not usually accommodated, so a lot of potential energy is lost unless one stands up from the saddle - which is inefficient anyway. So they are not of much use for road-cycling, but I have seen them used for that.

Interestingly, riding a correctly-sized bike in a low gear a lot is recognised as a very good way to repair knee damage in patellofemoral arthritis. I know this to be the case from personal experience - because it was the recommended remedy/treatment to repair the patellofemoral damage I had unwittingly incurred between the ages of 16 to 20 from too much ski-ing, weight training with heavy squats, distance road-running, and intensive soccer-playing. The arthritis surfaced painfully in my 30's whilst I was walking/climbing over some NZ mountain ranges and since then has been one good reason I try to keep regularly cycling. The arthritis thus rarely bothers me as the rough bits (criss-crossed grain of repaired cartilage) on the joints at the back of the patellas are kept smooth/polished and healed by virtue of the gentle repetitive cycling motion (in low gear), which also stimulates blood flow to the joints to help repair/maintain the damaged areas.

wraith808:
I think I understand most of the points you make above, but am confuzzled where you say:
Quote from: Shades on July 23, 2017, 02:09:57 PM
But if you cross your arms in front of your torso and bring your torso down towards the curved handlebar, so that your hands have good grip on the straight part of the curved handlebar, the aerodynamic efficiency is almost equal to that of a mountain bike, there is no strain on any injured elbow or wrist and you still have the advantages of the city bike model.
- "cross your arms in front of your torso"? How does that work?   
-IainB (July 24, 2017, 03:10 AM)
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Hard to put into words in a post, even for a native English speaker.

IainB:
Apropos of this:
Then today I read about this lady Belgian cycling cheat. It was disturbing enough for me to read a couple of years ago of the revelations about Lance Armstrong's enhancement drug-taking - which retrospectively cancelled all his prior TdeF wins (and quite rightly so) - but I had not realised that one could now cheat with "mechanical doping" - fitting concealed electric motors on the bike. Amazing what some people will do to "win".
-IainB (April 26, 2016, 05:35 PM)
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Just saw this video today. Pretty impressive and well-concealed technology.
Exclusive: we tested the rigged race bike (Is in French, but self-explanatory.)

Shades:
That video is old news. Several cyclists have cut their sporting career short when they applied this concept to their bike(s). And rightfully so. Still, the idea and execution is excellent, but not for sports. The consumer market would benefit greatly from this concept. And likely much more money to be made. As I am Dutch and grew up using bicycles a lot, I would even consider using such a bike here in Paraguay. Traffic can be very problematic here and a commute that lasts 20 minutes without traffic can easily take a1 to 1.5 hour with traffic.

With such a bike traffic wouldn't be any problem anymore, I would get (more) exercise than I do now and I won't be sweaty all over after using the bike. With the amount of sun hours here in this country, I think iit is possible to charge it using solar energy alone, during work hours. The model of bike that is used in the video above, I wouldn't use. A city bike would make much more sense, as you can easily pick up your daily groceries too. Without wasting time finding a spot for your vehicle and hoping no-one else dents your car. I see only advantages with this concept. Bicycles that have a way to assist their user have a few things in common. They are all very ugly to look at and it is easy to steal the parts providing the assistance. Hence you pay a lot for insurance of such a bike. All of that is gone with this concept.

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