22

First things first: A belt is probably slightly less efficient than a properly installed clean chain. The test you link already indicates that. Probably with the tension Gates requires you'll loose a bit more power. On to your question: The chain is 200 grams heavier than the belt, of course with the chain you get gears, which you don't get with a belt ...


14

The general idea of "lever drive," or a reciprocating pedal motion instead of a rotary pedal motion precedes even the invention of the modern diamond-frame bicycle--consider the Special Star from 1886. More recently, there was the Facet Biocam, the Alenax, and the Wall Walker. Within the world of reciprocating drivetrains, the String Bike is interesting in ...


10

Riding at 30kph average for 3 hours, in a hilly area is a solid effort. Assuming your pack riding skills are sufficient, you will also likely do fine in in a club ride that averages 30-40kph (but see the pack riding primer below). Club rides will have a faster pace than what you are riding now, but you will also be working a lot less (about 30% less) at any ...


10

You basically get what you pay for, so there isn't any secret formula. Trek is one of the largest manufacturers on the planet, and is probably as good as any other on the market. But have a look at, and test if possible, other bikes as well as Trek, because different models have different geometries, and another geometry might feel better to you. Size also ...


10

The most likely problem is that the brakes are rubbing. If you pick up the front of the bike, hold your head near the brakes and spin the wheel you shouldn't hear any noise from the brakes. If you do, then the brakes are rubbing and that's the first problem to be fixed. To be honest, I'd guess that's 99% likely to be your problem. If you have fenders, ...


9

I am continuously amazed at the overemphasis placed on the weight of bikes. Yes it is important, but relative to other factors in deciding which bike to buy it is not that significant. Lets compare a 20lb bike to a 24lb bike. If your budget is $1000 for a new bike, would you choose a 20lb bike with very good components and a so-so feel/fit, or a 24lb bike ...


8

Everything is relative. For 99% of the population 30kph for 3 hours would be amazing. For a male A grade club rider it would be an off day. For a female A grade club rider it's not bad for a solo training ride. About bunches Sometimes an ad hoc bunch forms in a popular road. These can be dangerous - you don't know the experience level of these people, ...


8

Not easily. V-brake levers pull twice as much cable as a calliper brake levers, so you'll not be able to swap them without swapping the levers too, and these are often attached to the shifters, so you'd end up swapping an awful lot of parts. Additionally V-brakes are mounted to a pair of bosses on the seat stays & fork legs whilst calliper brakes are ...


8

It seems like scientists tend to test athletic performance. The actual benefits of clipless pedals are: If you are cycling fast, you get a lot of unanticipated jolts and vibration which can make you slip off of the pedals, particularly if it is wet, muddy or bumpy. Clipless pedals keep you locked in. If your visibility is impaired by riding in the dark, or ...


8

Bicycles, like many machines, are efficient, but a large amount of energy converted by them is not in fact used for their "intended" purpose: The largest energy sink is air/wind resistance, which you can only very marginally improve on a "normal" bike†. However, wind resistance squares in relation to your speed, so maintaining a more leisurely pace would ...


7

I'd recommend a Cyclocross bike (also called CX). That's a robust road bike frame, configured to accept tyres up to about 40mm wide. You won't need 40mm unless you're doing proper off-roading, but a nice 30-35mm file tread such as a Specialized Trigger or Schwalbe Sammy Slick will run nicely on smooth pavement, will handle cobbles and bad pavement, and ...


7

Are you asking about the immediate effects while high or long-term effects? I can't find any unbiased, well-cited sources except for one from the British Journal of Sports Medicine which basically says that doctors should try to keep athletes from using cannabis due to its possible dangers. However, some sources (of unknown quality) claim that it may help ...


7

This is a deceptively complex question because it touches on many aspects of hub design, and answering it properly would also require taking some kind of survey of what design choices have wound up getting made for the various convertible vs. dedicated size through axle hubs, particularly in terms of what bearing sizes are used. Furthermore, for practical ...


6

Small changes in bike fit make dramatic differences in performance. Heat and humidity make a big difference.


6

The short answer is that it is purely down to your individual training level and mechanical efficiency in each of these disciplines. Bonking is a result of fully depleting your glycogen stores. Once this occurs, your body's only source of fuel to power your exercise is to metabolise fat. This does not change regardless of what activity you are performing. ...


5

Because wind resistance is proportional to velocity squared it takes more power to go from 30 to 32 than from 15 to 17. So you get more bang from your pedal power at lower speeds. If it is a relatively short downhill and you have considerable speed you are typically better off coasting and then pedal when you get to a flat or flatter section. So you are ...


5

The optimum pressure for any kind of bike is going to depend on a lot more factors than just the type of bike. You have to look at many other things such as rider weight, terrain, and tire size. It also depends on how you qualify something as optimum. Higher pressures might be optimum in some situations, but may not be very comfortable to the rider, making ...


5

Training plans are all well and good, but the first goal is to be able to ride 9 hrs. There is no substitute for doing long rides to prepare to do a long ride. In my experience, for just developing pure endurance you get 80-90% of your training effect from a long ride. The rest of your training should be focused around reducing the recovery time to enable ...


5

Has anyone experimented with using consumer 3D software to do CFD-like aerodynamics simulations? - Yes Could there be any worthwhile insights gained from this? Yes However, you should not view work like this as an alternative to using a powermeter or windtunnel testing. View it as a tool that can be used as an extension of sound methodical testing, to test ...


5

Surprised there are not more studies on efficiency of clipless. The original question was to seek a scientific answer, not anecdotal, although many feel clipless gives more, this is subjective if not backed by science. This is the only article I found: http://www.radlabor.de/fileadmin/PDF/PowerForce/Mornieux___Stapelfeldt_Artikel_Feedback_Pedalkraefte_2008....


5

I'm a commuter who has to carry things like books, a notebook, food for the day, bike lock, etc. I should say that it makes a striking difference whether you carry stuff on your back or on a bike rack -- a heavy bike is not as bad as a heavy backpack, in other words. Another thing that I've noticed is that my performance decreases if I ride five days a week ...


5

If you are looking for pedalling performance, adjusting the seatpost (up and down) and the seat (back and front) is the answer. There are literature about adjusting seatpost so you can look them up on the internet; youtube also have many video demonstration. Adjusting handlebar height is more about efficiency. In general: the less up-right position, the ...


5

The markings on the tires for the pressures can be essentially ignored. They're a combination of marketing and legal departments coming up with essentially arbitrary numbers. Find a set of pressures that works for you so the tires are properly inflated -- it should prevent pinch flats, but keep rolling resistance low and absorb road hazards and ...


5

The first answer is: you bike most efficiently inside a peloton (where air resistance is lowest) The second answer (in a GCN video of a sprinter): you do a lot or close to no effort in order to stay at a certain speed (stay on the average). Any increase of speed means you lose a lot more to aerodynamic effect. This usually means you give everything on ...


5

General Rule of Thumb: Go harder on "slow" parts (especially uphills), go easier on "fast" parts. This rule of thumb has two separate justifications: (1) Uphills or on slow surfaces (rough pavement or dirt) your air-speed is lower so a marginal increase in speed costs much less power since less force is being lost to wind resistance. This is because the ...


4

Boozing the night before has a dramatic effect.


4

Some factors that affect day to day athletic performance are: the degree to which your muscles have recovered from previous strenuous work. It is impossible to push the pace everyday, and hit a consistent performance level. Day to day consistent performance is only possible (far) less than maximal effort. symptom-free infections. It's possible for your body ...


4

I was answering the Physics.se version of this question but it got closed (probably rightly so), so I'm posting it here. The lighter pedals will have very little effect on the performance of your bike, other than through the overall weight, and particularly if you're pedalling at a steady cadence instead of accelerating and decelerating repeatedly. Making ...


4

A perfect book for beginners in training is Joe Friel's "Cyclist's training bible". The main point he makes in his book is training periodization i.e. changing the volume and intensity of training depending on when you want your peak to occur. In your case this is simple as you have a single goal. In general the rule is: low intensity, high volume through ...


4

The Science behind bonking This is a really interesting article applied to running but no doubt the same applies to cycling. The interesting quotes being "It is impossible to prove that muscle glycogen depletion alone limits prolonged exercise performance," and "the inseparable relationship between our head and our legs" And this highlights that glycogen ...


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