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标题: 怎样选购自行车？（英文） [打印本页]

作者: thesunlover 时间: 2008-8-8 15:43 标题: 怎样选购自行车？（英文）

How to Choose a Bicycle

There many different types of bicycles and many different types of people with different biking needs. Some people like tricks, some like races, and some like speed control. You will need to take into account your own preferences when choosing the right bicycle for yourself.

Learn how to ride if you don't already know. That's the first and most important step. You can do this on practically any bike that is the right size for you, but starting on a basic single speed bike with coaster brakes is usually best, since you don't have to worry about shifting gears and front/rear braking sequences.

Learn about the basic types of bikes.  Here are a few examples, with a brief description of each.

Standard bikes: These are old-fashioned, single speed bikes with coaster brakes (pedal backwards to brake).  Good for leisurely riding around town if there are no serious hills or other obstacles.

BMX bikes: Low profile bikes with 20 inch, usually knobby tires.  These are for "competition" biking on trails or courses. And have cable operated caliper brakes on the front and rear. These bikes are single geared bikes.

Road bikes: This is a general term for traditional bicycles designed for good performance on pavement.  There is a wide range of choices within this category; often they can be classified into the two broad groups of racing/performance or touring.  Racing bikes are designed for pure speed with an emphasis on light weight, and place the rider in an aggressive posture.  Touring bikes are designed for sustained comfort and carrying loads.  They have heavier components for durability, mounts for rack and fender attachments, and have a more upright riding position. Road bikes traditionally have "drop" or "aero" handlebars which allow the rider a range of hand positions for comfort or for achieving an aerodynamic riding position.

Mountain bikes: Bikes designed for offroad use, with compact frames, stable handling, clearance for wide and knobby tires, and higher handlebars for a more upright position.  For hilly terrain these bikes will generally come with low-range gearing.  There are many types designed for specific purposes, such as downhill versus cross-country racing.  They can be equipped with sophisticated suspension and disc brake systems.  Mountain bikes are also very popular as all-around bicycles due to their versatility; with slick tires they can be efficient on roads.

Tandem bikes: These bikes have an extra seat and set of pedals for two people to ride together.

Recumbent bikes: These bicycles seat the rider in a "reclining" position with the pedals forward, which is a more natural position requiring less flexibility than upright bikes.  They can be fitted with windshields for good aerodynamic performance.  However they are generally heavier and can't match the performance of racing style upright bikes.

Choose a mountain bike if you like going over large bumps and dirt. Many mountain bikes have at least a front suspension, to improve comfort and steering control on rough surfaces.  Mountain bikes can also be good for general urban riding, due to the stability and for going over curbs and the like.  Beginners may find mountain bike handlebars and controls easier to use.

Think about your intended usage.  If you don't intend to ride on unpaved trails, a road bike will be more efficient.  But the racing style bikes will not be very comfortable or practical for casual or practical riders.  It can be difficult to find more comfort-oriented road bikes in shops; they tend to push either racing bikes or mountain bikes.  A popular middle ground is the "hybrid" style bike.

If you intend to mount a basket, saddlebags, or a baby seat, you will want to be sure the frame is compatible with these devices.  Many bike shops have complete assemblies with these attachments already mounted, so there will be no doubt of their suitability.

Road and mountain bikes usually have gears and shifters, usually operated by some kind of trigger.  They are very useful for most riders, especially in hilly terrain, or for high performance.  They let you adjust your pedalling effort to account for hills, wind, or your own fatigue.  However, these systems also add significant cost and complexity (and weight).  For this reason, or just for the challenge, some riders choose a bike with a single gear ("singlespeed" bikes).  Any bike can be converted to a singlespeed, but unless the frame is designed for it, a chain tensioner will be required.

The fit of the bike is essential to consider.  Different bikes have different dimensions for varying body types.  Make sure the straddle height isn't too high for you, so that mounting and dismounting will be comfortable and easy.  Bikes come equipped with tires from 12" for children's bikes, up to a standard 26 inch, for adults, and even higher for specialized racing bikes.

Test ride a bike before you buy it.  If you can't get the bike shop to let you try theirs out, go to another shop, or borrow one from a friend.  It is easier to get a bike that fits, than to adjust and get acclimated to one that doesn't.

Buy or have your bike professionally assembled.  This is especially true with derailleur equipped bikes, but having it done professionally insures all the nuts and bolts are installed and tightened correctly, and all the accessories are properly fitted and adjusted correctly, as well.

Buying a bike will be much easier if you choose a bike shop rather than a "big box" store, since the shop should employ knowledgeable people who can help you make a good choice.

Mountain bikes are often bought for use as general purpose road bikes. While they are comfortable and easy to ride on the road, there are two things to watch out for if you only want it as a general purpose road bike:

Get mudguards: one problem with mountain bikes is that they are really intended for off-road cycling where mud, leaves and sticks could get caught in the mudguards, therefore they tend to not have mudguards. For your daily cycle on the road, mudguards are essential (otherwise you will get a muddy streak up your back, and other cyclists and road users will get covered in your spray when riding being you). Unless you really want your mountain bike for serious off-road cycling, insist on good quality mudguards, that cover the whole wheel (not just one of those so called 'crud catcher' style plastic guards that fit below the saddle - save those for off-road cycling).

Avoid chunky tyres: mountain bikes tend to have very chunky tyres, with deep a tread. This sort of tyre is essential for gripping in muddy conditions, but on a road (even a wet one), the deep tread only serves to make cycling difficult. The extra energy required to pedal with chunky tyres is considerable. You can hear the low hum that they generate! So, unless you really need the bike for serious off-road riding, you should get tyres with shallow tread. Smooth slick-tyres are good for road riding, but mostly for racing, they can be slippery in the wet and expensive. However there is a good range of general purpose road tyres with shallow tread, these make an excellent tyre for a mountain bike for use on the road.

Mountain bike handlebars can become uncomfortable after a while when your hands are in the same position for too long. There are a couple of things you can try to do about this. One is bar ends: these are extra "horns" that stick on the ends of the handlebars and provide an alternative grip. They can also make it easier to get your body forward for climbing or pedalling into the wind. Another option is the grips themselves; some companies such as Ergon make grips with a more anatomical shaped bulge which you may find more comfortable than the simple round tube grips.

http://www.wikihow.com/Choose-a-Bicycle

作者: thesunlover 时间: 2008-8-8 15:52

What's the best bike for you?

When you start your shopping you will find there are generally five bike categories (exempting kids bikes and specialty bikes like tandems).

Mountain Bikes

These bikes are designed for off road and rough terrain biking with

chunky, bumpy tires for good traction
straight across handlebars for better handling
low gearing for hills and dales
front or full suspension to cushion the ride.

Plan on spending from $400 for basic trails to $700 or more if you are interested in serious off road terrain, sharp climbs and just as sharp descents.

Straddle the bike and make sure you can stand comfortably. With mountain bikes you may need to stop quickly and will need all the balance and traction your feet can afford.

The frame is important here, in that you need enough room from the handlebars to the seat for comfortable standing and pedaling.

Suspension comes in two varieties, something like front wheel drive and four wheel drive on your car. Most of these bikes include front suspension to cushion the terrain. Full suspension makes for quick descents but increases cost and weight, and you are going to have a harder time pedaling.

Road or Racing Bikes

These bikes are designed for aerodynamic riding or racing on the street with

skinny, smooth tires
curved handlebars to increase speed
a light frame

There is a spread in the cost of these bikes, so seriously consider your needs. If this bike is for heavy duty racing or cross country riding, $1000 is not out of the question. Scale it back to $500 for a bike that will last a long time and offer good braking and smoother shifts. If you are an occasional weekend rider, you can find a good bike for around $300.

Comfort is a high priority with these bikes. If you don't like the extreme bent seating contortions of some racing bikes you can get a bike with a higher handlebar. Seats can be exchanged for larger saddles with deeper cushions or anatomic designs. Another consideration is the distance between the seat and the handlebars...too long a distance and you will be straining...too short a distance and you will feel restricted. Make sure you can move your hands on the handlebars and that they are not receiving all your weight.

Unless you plan to compete consistently, there is no need to opt for the uber lightweight bikes. They will shortchange you in stability and endurance. If you are over two hundred pounds, don't even think about it. Also keep in mind the tires on a racing bike can be anorexically thin and demand a higher skill level.

Hybrid Bikes
These bikes are designed for mountain biking and pavement riding and are a marriage of the two that might fit your needs. However, the hybrid is not designed to be a perfect mountain bike, nor a perfect racing bike . Picture a mountain bike with

slimmed down tires
lighter frame
straight bars
higher gear levels

Cruisers

These bikes are designed for the road, the beach boardwalk or very casual riding. Look for a bike that has

chunky, smooth tires
big frame
no speeds or three speeds
back pedal brakes or hand brakes
upright seating and handlebars

Comfort Bikes

These bikes are designed for a comfortable ride without neglecting high performance. Look for

upright seating and handlebars
cushioned seat
lower gears

http://www.abbysguide.com/bike/guide/best-bike-for-you.html

作者: thesunlover 时间: 2008-8-8 15:54

The final word on bikes

If you are going to use the bike for anything but the most casual of uses, buy a bike from a reputable bike shop.

For off road on rough and steep terrain buy a mountain bike. For shorter rides on pavement, commuter travel, or smooth off-road trails, buy a hybrid. For racing, or long distance riding on up and down pavement, buy a road or racing bike. For back and forth to the local library, etc., buy a comfort bike or a cruiser. And always wear a helmet.

作者: thesunlover 时间: 2008-8-8 16:07

Mountain Binkes

These type of Bikes are spicily designed for demanding terrain. These bikes are for bikers intending to ride in off road terrain. Of course, road and path riding is possible as well but its design and tyer type predetermine the bikes for rough terrain. The bike’s price reflects how demanding the terrain is.

■ Frame EASTON Ultralite carbon seat stays EASTON alloy 26″
■ Front Fork MANITOUR7 Super air lock out (100 mm)
■ Rear Derailleur SHIMANO XTR rapid rise
■ Brakes HAYES El Camino Ti disc hydraulic 6″ rotors
■ Tires RITCHEY Z-Max Evolution kevlar26″ x 2.10″

This model for race-designed mountain specials built for dynamic and long-lasting rides (marathons), allowing an experienced rider to employ all his/her power and technical skills in long run ups to models for sports and semi-advanced riders intending to achieve sports results in medium-difficult fields.

附件 1 : mountain-bike1.jpg (2008-8-8 16:07, 132.88 K )

作者: thesunlover 时间: 2008-8-8 16:11

Cross Bikes

Universal bikes, for terrain trips, roads and paths. These bikes are for bikers intending to use the bike roughly 80% in fields, forest paths and roads. The bike can be used in light terrain for brief periods. The frame design is adapted to more comfortable and open seating when compared to a mountain bike. Recently, this bike type has been very popular and pre-determined for bike tourism. Optionally, you can have trekking bike (if equipped with mudguards, lights, carriers etc.).

■ Frame AUTHOR COLUMBUS Zonal alloy 700C
■ Front Fork RSTVogue TnL oil lock out (60 mm)
■ Rear Derailleur SHIMANO XT normal
■ Brakes TEKTRO MT-14
■ Tires AUTHOR PANARACER Silk Road Cross 700C x 35

Cross bikes represent multi-functional sports models intended for riding on dirt roads as well as public roads. Cross bikes are characterized by their excellent manageability, comfort and safety. For many years, AUTHOR has been a famous brand for this type of bikes. AUTHOR cross bikes are popular because of our detailed knowledge of this bike segment. We offer the widest range of frame sizes, we have developed own cross tyre casings and we use AUTHOR rims on the top performance models. We design technical solutions of comfortable gel seats and special ergo-metric handlebars and extensions.

附件 1 : cross-bike2.jpg (2008-8-8 16:11, 133.85 K )

作者: thesunlover 时间: 2008-8-8 16:13

Touring Bikes

Bikes mainly for roads and compacted paths. It is completely unsuitable for any terrain riding. The touring bike can be used as a means of transportation thanks to its equipment (mudguards, lights, carrier etc.).

■ Frame alloy 700C
■ Front Fork RST CT-COMI T7 (50 mm)
■ Rear Derailleur SHIMANO Acera
■ Brakes TEKTRO 57 AL
■ Tires CST C-1447 700C x 40

This type of bike is more in demand from riders preferring (riding) comfort over extraordinary sports performance and in most cases, they use their bikes on roads and not in the field. We are proud to meet the requirements of the most demanding clients who expect limo properties from a bike.

作者: thesunlover 时间: 2008-8-8 16:15

Road Bikes

These are sports bikes for roads and closed circuits. Do not use this type of bike in terrain in any way.

■ Frame AUTHOR carbon 40T monocoque
■ Front Fork AUTHOR carbon 40T monocoque
■ Rear Derailleur SHIMANO Dura Ace
■ Brakes SHIMANO Dura Ace
■ Tires PANARACER Stradius Extreme kevlar 700C x 23

Racing and sports road bikes whose structure and shifters are based on proven and professional rider-used geometry of frames. The frames are the cornerstone of the whole collection of road bikes, featuring compactness associating the attributes of extraordinarily low weight, high frame rigidity as well as high strength.

作者: thesunlover 时间: 2008-8-8 16:16

BMX & Free Style Bikes

Bikes either for closed circuits or compacted closed surfaces intended for this bike type. Absolutely not suitable for long-distance transporting.

BMX (Bicycle Motorcross) is a form of cycling on specially designed bicycles which usually have 20 inch wheels. The sport includes racing on earthen tracks, known as BMX racing, as well as the performance of tricks on the bikes, called Freestyle BMX.

Freestyle BMX has grown to include five distinct disciplines. These are Street, Park, Vert, Dirt, and Flatland. These usually involve technical movements of the bike in different ways over varied terrain.

A BMX intended for racing can be easily picked out from a freestyle BMX. Freestyle bikes usually have a U Brake instead of a V Brake and a race BMX has longer stays to increase stability when going faster. The shorter wheelbase of a Freestyle bike allows quicker turning.

附件 1 : bmx_bike2.jpg (2008-8-8 16:16, 60.6 K )

作者: thesunlover 时间: 2008-8-8 16:17
http://blog.bikesbargain.com/bikes/how-to-choose-a-bike/

to be continued....

作者: thesunlover 时间: 2008-8-8 16:19
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作者: thesunlover 时间: 2008-8-8 16:20
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作者: thesunlover 时间: 2008-8-8 16:21
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