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Text originally from the Easterley Road Club. Original text HERE.

First you must decide what type of riding you are going to do. Will it be on the roads or off-road? Will it be for racing, touring, or commuting? If it is for racing, what kind of racing will you be doing - road racing, track racing, time trialling or mountain bike racing?

Mountain Bikes

90% of the mountain bikes sold in this country are never ridden off road. Most are used for commuting or just sit in the shed. If you are going to use it regularly off road then there is nothing better than a mountain bike for this purpose, however they are heavy and unresponsive when used on the roads. If you only want the one bike but you also wish to commute, then a second pair of tyres with a narrow, slick tread can make a big difference to the performance of the bike. You may even consider having a second set of wheels built especially for this purpose. These tyres give the added benefit of better handling and grip than knobbly mountain bike tyres on wet tarmac.

Road Bikes

Do you intend to race, commute, tour, or a mixture. A good compromise for all three is to purchase a winter training bike. This will have a reasonably light weight and responsive frame, narrow wheels and room for mudguards, The advantage with this type of bike is that the mudguards can be removed and narrower tyres fitted for racing without sacrificing too much performance in comparison to a purpose built racing machine. Alternatively carriers for saddle bags and panniers can usually be added and the gears adjusted for touring.

Purpose built touring bikes will tend to have larger clearance for mudguards and larger tyres, a wider range of gears, and the carriers already fitted; whereas racing bikes will have narrower tyres, higher gears and close clearances.

If you intend to race but are not sure what you kind, a road racing bike is a good first option as tri-bars can be added for time trials or triathlons, and then removed for road races (you are not allowed to use them in bunched races).

Custom built or off the peg?

Most bikes bought by novice cyclists are already built up with all its components, however you may wish to go for a custom built bike. Buying off the peg is usually cheaper than buying a frame and components individually, however there are often some cost saving items the manufacturer has included that may have to be replaced within a short time. A custom built machine gives you the opportunity of having exactly what you want.

Go to a reputable dealer and get advice. If you are unsure about what to buy, ask someone in the club to come along with you.

Frame

The frame is the heart of a good bike. Look for a bike with a good frame, even if the rest of the equipment is not as good. Remember that the components can always be upgraded at a later date.

Steel

The most common material for a frame is steel. Look for a frame that is made from a steel alloy such as Chrome Molybdenum (CroMo) or Manganese Molybdeneum (MangMoly). Most of the frames you should be looking at will say which company manufactured the frame tubes (as opposed to who constructed the frame). Names to look out for include Reynolds, Columbus, Dedeccai, Vitus, Oria and Tange.

Alternatively you can go to a specialist frame builder who will build one up to fit your measurements and specifications. There are few frame builders who have the technology to build in anything other than steel or aluminium.

Steel has the advantage of being sturdy, responsive yet forgiving on rough roads, can be repaired by a frame builder quite easily in the event of accidents, and probably represents the best value.

Aluminium

Aluminium frames are the next most common. They can be lighter than steel but are usually more expensive. They can also be made stiffer than steel through the use of larger diameter frame tubes (which increases the fatigue life compared to narrow aluminium tubes) but this can make for a harsh ride on rough roads or tracks. They will require specialist knowledge to repair them however. Many aluminium frames now include carbon fibre front forks and seat stays.

Carbon Fibre

These can be made either from either tubes or a monocoque (e.g. Chris Boardman’s “Lotus”). They can be very light but also very expensive. They tend to be reserved for top of the range racing bikes.

Titanium

Titanium is expensive and difficult to work with but is also very light and stronger than aluminium. It also has a natural spring that makes it more forgiving than aluminium. Again these frames tend to be for top end racing bikes.

Frame Sizes

Having the correct size of frame makes for a good position on the bike, and therefore a more comfortable ride.

Frame sizes can be specified in either inches or centimetres. If the frame size is in inches, then this is usually the measurement from the centre of the bottom bracket to the top of the seat tube (or ‘centre to top’). Continental frame sizes are given in centimetres and are usually measured from the centre of the bottom bracket to a point in line with the centre of the top tube (or cross bar) (‘centre to centre’). However to complicate matters, some British frames are also measured in centimetres but from centre to top! It is always worth checking how the frame is measured before buying or ordering.

The top tube length is always centre to centre.

Another complication is that many frames now have 'compact' geometry where the seat tube is shorter than usual and the top tube slopes down to the rear. This gives a smaller and therefore stiffer rear end. Ask the dealer to give you the virtual measurements of the frame - i.e. as if the top tube was horizontal.

The following table gives a rough guide to the size of road frame you should buy.

Inside leg is measured from crotch to the ground.

Inside Leg Seat Tube Top Tube
Inches Cm Inches Cm Inches Cm
(C to T) (C to C)
29 73.5 19.0 47.0 19.0 48.5
30 76.0 20.0 49.5 20.0 51.0
31 78.5 21.0 52.0 20.5 52.0
32 81.5 22.0 54.5 21.0 53.5
33 84.0 23.0 57.0 22.0 56.0
34 86.5 23.5 58.5 22.5 57.0
35 89.0 24.5 61.0 23.0 58.5
36 91.5 25.0 62.5 23.5 59.5
37 94.0 25.5 63.5 24.0 61.0
38 96.5 26.0 64.5 24.5 62.0

However these sizes are only a guide and as everyone is different, then you may need to adapt accordingly, either by having a frame custom built or by varying saddle height and handlebar extension length.

With mountain bike frames however, sizing is more difficult and will depend more on rider ‘feel’ than on any hard and fast rules. The length of the top tube is more critical than the seat tube length (as mountain bike seat pillars are longer and therefore have more adjustment). The longer the top tube, the more stretched out you will be on the bike. Novice riders tend to prefer to be more upright and so will require a shorter top tube whereas a racing mountain bike’s will be longer. Also look for a frame that will give you at least 2 inches clearance between crotch and top tube when standing astride the bike.

Alternatively you may wish to have a computer program calculate the size of frame for you. Certain cycle shops operate the Bioracer computer system (http://www.bioracer.com ). The shop assistant will take certain critical measurements from you (e.g. height, leg length, etc.) and send them to Bioracer. The Bioracer computer program will then calculate all the dimensions of the bike (seat tube, top tube etc. ) right down to the crank length, and saddle height, depending on the type of riding the bike is designed for. This is good way of avoiding any trial and error in setting up the bike although you will pay a fee for this.

 

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