Bike Set-up

Summary

Correct bike set-up is essential to allow safe handling, minimise the risk of injury, maximise power output and optimise aerodynamics. The following will give a neutral starting point, refer to the attached notes for detailed explanation.

• Frame size = inside leg x .65

• Saddle height = inside leg x 1.09 for men, 1.08 for women

• Cleat position- the ball of the foot should be over the pedal axle

• Saddle setback- with the cranks parallel to the ground a plumb line dropped from the top of the fibula should fall through the centre of the pedal axle

• Handlebar reach- place the back of your elbow against the nose of the saddle, your outstretched fingers should be between 25 & 100 mm from the back of the handlebars

• Bar height-start with the bars 25mm below saddle height

• Tri bar reach & angle- the reach should be set so that your ear is directly above the inside of your elbow, the bars should be level or sloping up slightly so that the bottom of your hand is above the level of your elbow. Arm rests as close together as possible without causing discomfort.

Always check that your position allows you to ride after swimming and that you can run once you get off the bike. Make adjustments gradually over time.

Frame size.

Unless you have the correct frame size you will probably never get a good riding position. The only way to get the correct frame size is to get measured in a bike shop and try different sizes and frame styles. As a rough guide to start with multiply your inside leg measurement by .65 for example inside leg = 84 cm x .65 = 54.6. Choose either a 54 or 55 cm frame. Different manufacturers use different methods to measure frames so always try them for size.

There are more Compact frames coming onto the market and this makes frame size choice a bit easier as many manufacturers only offer 3 sizes small, medium and large but they generally give an equivalent size.

Once you have the correct frame size set the position up in this order.

Saddle height

There are quite a few methods for setting saddle height but, to avoid confusion, I will give just the one that I have found most reliable. Measure your inside leg and multiply this by 1.09 for men 1.08 for women (if you have small feet multiply by 1.07) then with the cranks in line with the seat tube measure from the surface of the lowest pedal, along the line of the seat tube to the top of the saddle.

Knee pains usually mean that the saddle is too low, hamstring and groin pains usually mean it is too high.

If your saddle height is wrong adjust it by about 5mm per week until it is at the correct height. Too large an adjustment all at once can result in injury.

The saddle should be level or very slightly tilted forward.

Cleat position

Adjust the cleat so that the middle of the ball of your foot is directly over the pedal axle. Cleat alignment is a bit trickier and will require some experimentation but most pedal systems allow for some float making it less critical. To get an idea of your correct foot alignment jog on the spot for about 10 seconds then stop and look at the angle of your feet, this is roughly how they should be on the bike.

Saddle position

This will be easier if you have an assistant. Ideally set the bike up on a turbo trainer, insure that it is perfectly level. Pedal for a few minutes then stop with the pedals parallel to the ground. Have your assistant drop a plumb line from the top of your fibula (the bony bit to the outside and just below the kneecap) it should intersect the pedal axle. This gives a neutral position, you can move the saddle forward of this position by up to 2cm to give more power on short courses such as Sprint or Standard distance or further back for more comfort for longer bike legs.

Handlebar Position

· Reach, this can only be adjusted by changing the length of your stem, when you buy a new bike it is worth getting the shop to agree to change the stem to the correct length. Check the reach by putting the back of your elbow against the nose of the saddle, your outstretched fingers should be between 25 & 100 mm from the back of the handlebars, preferably nearer to 25 mm.

· Height, again an area for experimentation and adjustment but start with the top of the bars about 25mm lower than the level of the saddle.

· Tri-bar reach & angle, set the reach so that your ear is directly above the inside of your elbow. Set the angle of the bars so that they are level or sloping slightly up at the front. The fleshy part of your forearms should rest on the arm pads. When pedalling your knees should come close to the back of your elbows.

· Arm width, generally the closer together the better but remember to try the position after swimming. There has also been some research showing that, for some riders, a wide position works best but this is very individual and requires testing, for most people closer together is better.

Equipment

Body position is by far the most important factor in aerodynamics therefore the most important equipment is the equipment that allows you to get into a good aero position, proper frame fit, tri bars and the correct length and rise stem. An adjustable stem is great to get you into the best position to start with and then adjust for a range of distances.

Tri Bars

These are essential, they easily make the biggest difference and will save at least around 2-5 minutes over 40 km and probably a good deal more if your current set-up is less than perfect. The bolt on type are easier to ride with as they still allow you to use the normal drop bars as well. Dedicated all-in-one bars require a higher level of skill to control the bike and limit the bikes usefulness for training.

Choose bars that allow for a good range of adjustment, you should be able to alter the width, height and reach of the arm rests, and the reach and angle of the bars.

Wheels & Tyres

These are probably the second most important item, they make a big difference to the handling, feel and speed of the bike. The biggest upgrade is from the wheels that come as standard on off-the-peg bikes to something hand-built or the better quality ready built wheels.

If money is no object you can go for the lightweight and aero advantages of full carbon rims such as Corima or Zipp. If you don’t want to spend that much money (£500+) then the choice is likely to be between light weight or aero. I think that lightweight is better than aero for the hillier, and more technical courses where you are making repeated accelerations. Cheaper “aero” wheels tend to have very heavy rims to compensate for the low spoke count and very little, if any, real aero benefit. Even good aero wheels have very little advantage below 25 mph (40kph) so be realistic and think how much time you spend riding at this speed. I would choose good quality, hand-built wheels with lightweight rims such as Mavic Open Pro over the cheaper ready built wheels such as Mavic Cosmos.

Bladed spokes help, the thick fibre spokes are a definite hindrance, they make light comfortable wheels but create significant drag.

There are good arguments for and against 650 wheels but the balance seems to be against them. The strongest reason against them is that the short chainstays make the chain-line more acute and therefore gear selection critical. It is very easy to choose a gear that increases the chain angle too much and creates large amounts of drag. This seems like a vague argument but tests have shown that the extra drag does have very significant effects.

23mm tyres are definitely faster than 20mm tyres, honest. They have lower rolling resistance and are less likely to puncture. Go for good quality folding tyres, these have a better quality carcass which means they are more puncture resistant and roll faster. Buy good quality inner tubes too, the difference in price is small, but cheap inner tubes are very thick, heavy and increase the rolling resistance of the tyres. Latex tubes do give the lowest rolling resistance but they are expensive and they lose pressure very quickly.

If it is dry pump tyres up to their maximum pressure, they will go faster

Frames

Go for a good fit first, aero second. The aero advantage of even the most aero frame is comparatively small, Lance Armstrong’s custom designed Trek that was painstakingly designed specifically for him, in a wind tunnel will only save him around a minute over 50k on a pan flat course riding at 50 kph+. An off the peg frame will give nothing like that advantage, this is less than the difference a badly maintained chain would make.

Most frames are now aluminium, the best aluminium frames are lighter than the best steel frames but there is little difference lower down. Steel tends to be more comfortable, aluminium stiffer but harsher. Carbon fibre theoretically offers the best of both, light, comfortable and stiff but it is expensive. Titanium frames are very comfortable, they tend to be a bit lighter than steel but they vary widely in price and quality. Merlin, Lightspeed and Seven are at the top of the range and their frames are superb but expensive, Airborne (now available at Halfords) and Raleigh both offer good value titanium frames but they are quite flexible.

Some manufacturers offer women specific designs where the frame geometry and sizing are more suited to female proportions, reports are generally positive but they do tend to downgrade the specification slightly so be careful. Also the smaller sizes often come with 650 wheels, see above.

Shoes & Pedals

Riding in running shoes is not a good idea. Apart from ruining your running shoes you are much more likely to get knee injuries and lower leg pains because running shoes don’t provide any foot stability. You waste a lot of energy compressing a cushioned sole on every pedal stoke and it is almost impossible to develop good pedalling technique wearing trainers. Some track sprinters and die hard Roadies still use toe clips and straps but they use proper cycling shoes with very stiff soles and sole plates and the straps are done up extremely tightly.

Choose a pedal system that gives a large pedalling platform, allows some float (foot rotation) and is easy to get into and out of. The most popular system is Look, they are inexpensive and very easy to use, the only downside is that the plastic cleats wear quickly when you walk on them. Time are a good bet if you have knee problems, they allow sideways movement as well as float. Shimano & Campagnolo make their own systems that work fine, although the Shimano SPDR system can be difficult to get out of.

There are plenty of good shoes about, make sure you get a good fit and choose some that are quick to put on and get off.

Anorak stuff

Weight

The effects of light weight components seem to be a topic of interest for many triathletes, however the effects of weight on cycling performance may not be as significant as one expects. To illustrate the effects of weight the following table models a tough out-and-back 40k with a constant grade of 3% which results in 600m or about 1970 feet of climbing/descending with aerodynamic bikes that weigh 22 lb. and 17 lb., and a slightly less aero bike/position that weighs 17 lb.

TABLE 5: Predicted 40k time, 3% hill, out-and-back course, two body positions.

Bike Wt.	22 lb	17 lb	17 lb
Drag @30mph	6.3 lb	6:3 lb	6.8 lb
Elite	65:04	64:37	65:52
Well-trained	69:38	69:05	69:22
Trained	76:55	76:12	77:31
Recreational	87:24	86:27	87:47

An extremely light bike on a tough climbing course will only save you about 30 seconds to 1:00, but if this lighter bike compromises your aerodynamics even a little bit, you will be slower by 23-48 seconds. Races in Scotland almost always include hills but a good aerodynamic set-up is still the overriding objective to achieve a competitive time. Wheels are something of an exception to the weight rule because you are using power to rotate the wheel as well as propel it forward so that effect is exaggerated. This is particularly noticeable on technical courses where there are a lot of accelerations out of corners and climbing.

Water bottles

Bottles behind saddle is not a good option, although they appear to be hidden behind the rider they interrupt the air-flow and slow the rider down.

A bottle on the frame is better than an empty bottle cage and in a side wind can have a slight sail effect.

There is no data yet (as far as I know) on the aerodynamics of drinks packs but the fact that your pedalling or position are not interrupted when you take a drink should make them a good option.

Seat Posts

It seems that Aero Seat posts may not be very aero, particularly the long ones used

in compact frames. Recent research shows that by allowing air to pass between the seat post and the riders legs they create small amounts of turbulence. The effect is very small and not worth worrying about if you already have one but if you were thinking of buying one save your money.

Some Examples of Good and Bad Riding Positions

1. Rene Rovera, Bad, very bad! High, hunched back, wide elbows, forearms pointing down, poor arm position on rests. His riding position also looks unbalanced and he will probably loose time through poor bike handling and low power output.

2. Steve Larsen, Good. Nice flat back and head position, arms tilted slightly up, elbows close together, arm reach correct and a good powerful position in the saddle. Steve Larsen did the fastest bike split, 112 miles in 4:33 averaging just under 25 MPH on a very windy day!

3. Scary! Chris Boardman many years ago, very low at the front, elbows almost touching. The hollow space between his head and back would normally be filled by a head faring. Chris Boardman is capable of riding at 55KPH for an hour or more but, anyone who saw him break the hour record last year may have noticed that he had to be lifted off the bike afterwards and was unable to stand let alone run, not good for a triathlete. This was due partly to sheer exhaustion but also to his extreme riding position. Be warned, it is worth making sure that you can get into your aero position after swimming and that you can run afterwards.