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I just saw this guy called Jason Rourke breaking the record of 112.94mph (181km/h) on his bicycle. I wish I could have such a bicycle to ride, but I have never ridden a racing bicycle with gears.

I want to use the bicycle for the 26-30mi commute that I do everyday and if it is a racing bike it could potentially save time. But I have some doubts/questions:

  1. Do these cycles really produce speed of around 60 - 70 km/h? If so, where could I get them?
  2. Are these stable at these high speeds of about 50km/h?
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The bike doesn't produce the speed, the rider does. But 50km/h is only about 31 mph, a speed I can relatively easily achieve on a modest downhill with my touring bike. A good bike should be reasonably stable at this speed so long as the road is reasonably smooth. –  Daniel R Hicks Mar 19 at 11:50
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You hint that you're currently riding an inexpensive single speed bike, likely with fat tires. Switching to even a good quality "hybrid" bike with derailleur shifting and well-chosen road tires inflated to a reasonably high pressure should make your ride significantly easier/faster. (A real "racing" bike is far from comfortable and likely impractical for your needs.) –  Daniel R Hicks Mar 19 at 11:54
    
An average fit cyclist probably cruises on flats at around 25km/h to 30km/h at a fast pace on a road bike. An pro racer cyclist might go 35km/h to 40km/h at a fast pace. As a commuter, you'll probably be going slower than either of these (as not to get soaking wet on the way). –  Benzo Mar 19 at 12:43
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Note for your link: That bike was built by Jason Rourke, it was ridden by Guy Martin. What makes it so fast is motor pacing - he was cycling very close behind a truck. This makes a huge difference in terms of air resistance, so allows much faster speeds. –  vclaw Mar 19 at 12:47
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I wouldn't even consider this a racing bike. It's a dedicated time trial bike for attempting speed records. You wouldn't even consider riding this in a race setting, or any setting involving other riders, or on a street. It's impractical for anything except cranking up to a ridiculous speed on a straight and even course. –  Benzo Mar 19 at 12:52

5 Answers 5

up vote 6 down vote accepted

I want to use the bicycle for the 26-30mi commute that I do everyday and if it is a racing bike it could potentially save time

A trained cyclist can definitely ride farther and faster on a road bike than on a hybrid bike, based solely on wind resistance and bicycle fit. However, the speeds you list are completely unrealistic. Bike speeds are based primarily on the rider. Other major considerations include the route and the physical shape you want to arrive in.

A 30 mile commute means you are riding 15 miles in each direction. I know a lot of people who bicycle commute this distance every day. They are all in excellent physical shape and ride at least 2,000 miles a year. (3,218 kilometers)

Assuming:

  1. A 15 mile route with few if any stops
  2. A good road surface (paved, minimal bumps)
  3. Few intersecting roads
  4. Dry weather
  5. Fairly flat ride

All of the commuters I know could easily finish the ride in less than 1 hour. (averaging over 15 mph). Many of them could average 18 mph for the entire ride. A few might be able to average 20 - 21 mph.

However, They will all arrive at their destination dripping sweat and need a shower and a change of clothing. If it rains, your average speed will go down significantly, since it just isn't safe to ride as fast on wet pavement.

So practically speaking, unless you are a highly trained athlete, doing 15 miles any faster than 20 - 21 mph is probably out of the question. Much more likely that you will do 15 - 18 mph. (And that's for a trained cyclist.) You then have to worry about cleaning up once you reach your office.

Getting one of the special bikes you mentioned will most likely slow you down, since they are designed for ultra high speeds with gearing that simply won't work in a city.

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Guy Martin is obviously a decent cyclist, but you should note that his record-breaking ride occurred under very special conditions. For starters, he built his own frame (or rather Jason Rourke built it for him). Next, he chose exactly where the run would take place - on sand flats. And not least he was towed in order to get up towards top speed, which dramatically reduced air resistance.

All of these things make comparing his ride to how you would ride, like comparing apples and oranges.

To get an idea of speed, you'd probably get more from looking at professional road racers. These guys will typically ride at speeds of maybe 40+ km/h. Put them on specialist time trial bikes and they will top 50km/h. And these are average speeds - you can imagine that gradient, wind and the ability to slipstream will be factors plus or minus. Certainly when descending, the 70km/h you mention is not all that much for them - I myself have gone at more than this speed and lived to tell the tale (I am far from being a fast rider).

But you need to bear a couple of things in mind. First, these people are professional athletes, which immediately sets them apart from the rest of us, their bodies are something south of 5% fat, and you can see that the muscles they have developed for cycling are disproportionately large. Second, the bikes the pros ride, a ballpark estimate of cost would be maybe $15000 - which buys you a lot of lightness. The typical weight of one of these bikes I'd guess is no more than 6 or 7 kilos.

Transpose all of this to you. As regards the roads you ride, how good will they be? Basically, the smoother the road, the faster you'll travel. If you had a road bike, how light would it be? Plus there's you - how fast would your legs take you? These are all factors that would affect how fast you could ride.

In answer to your specific points, as I said 60-70km/h is not a great deal under certain circumstances. I would imagine most road bikes could achieve this. So as to where you'd get them, the answer is pretty much anywhere. How often you could reach these speeds would be down to you.

Your second point, re stability. I'd argue that stability is as much a factor of the bike as the speed. One of the big differences you would notice between, say, a $1000 road bike and a $15000 bike would be stability. A lower end bike should be pretty stable, but will have limitations on performance. A higher-end bike will perform better but will also require more skill to handle. I have observed this to be true regardless of speed - high-end bikes are more responsive and therefore more "twitchy" (I'm thinking of stability here as how easy it is to control the bike). Its a bit like going for a ride on a donkey and going for a ride on a thoroughbred.

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Usually, when you want to commute somewhere, you have to carry things (a rack+panniers are good for this, esp. if you carry laptops), you don't want to arrive in a pool of sweat (and you need a change of clothes on hand anyway) and you want to arrive comfortably (cause you should be productive at work). These are all the opposite of what a racing bike is intended for. If you have urban sections, it doesn't really matter what bike since you'll be able to hit the maximum safe speed on any point. So, overall, a racing bike is a bad idea (unless you are a racing cyclist, and your "commute" is a race).

As for stability, its a combination of road surfaces and rider skill and geometry, but 50 kph is doable on a lot of road bikes. A lot of the "speed run" cycles are custom jobs in very controlled conditions, and don't necessarily sustain the speed for distances (the hour record of mercx was around 50 km, for example).

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Any half decent touring or racing bike can do the speeds you noted, however, a more practical value for commuting is ~10-20 mph, on flat terrain.

I'd recommend a touring bike for the purpose, rather than a racing bike for all the reasons noted previously.

They have slightly wider tires and sturdier frames. The first leads to a somewhat less bumpy ride, the second to being able to carry loads easily.

They also employ a less stressful (body) sitting position that racing bikes, which translates into less back and neck strain over time.

PS> there are a variety of bike shops in most urban areas and many offer a wide variety of models to choose from. Use the internet or your local Yellow pages to find the ones near you. I would avoid Wallmart/toy stores for the purchase, as the weight of the average toy store bike doesn't lend itself (imo) to communting

For reference, I ride a low end Trek. Cost me about $175 out the door, although that was 5 years ago, so tack another $50 or so to the price. Alll i've had to replace is tires and inner tubes. Oh, and I replaced the seat for one that has a gap down the middle to reduce strain on "man parts".

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For the first question answer is «Not». The problem is air resistance, starting from 40-45 km/h it's like a wall. For every addition to you speed you'll spend more and more power.

For the second — 50 km/h (and even more) is a normal speed for descents on a road bike. This bikes is pretty controllable on such speed.

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