the_custom_bicycle
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BICYCLE SETUP
Figure 20-1: Setting saddle angle. The front of the saddle should be slightly higher than the back of the saddle. Placing a yardstick on the saddle makes this critical adjustment easier to set. Never allow the tip of the saddle to be lower than the back of the saddle.
THE CUSTOM BICYCLE
Figure 20-2: Setting saddle height. The saddle height should be adjusted with the rider on the bicycle with both heels on the pedals. Adjust the height of the saddle to allow for a slight bend in the knee at the bottom of the stroke. Quick Check: Pedal backwards with both heels on the pedals. If the hips sway, the saddle is too high.
BICYCLE SETUP
Figure 20-3: Horizontal adjustment of the saddle. The saddle position from front to back is adjustable to compensate for individual variances in upper leg length and riding style. To correctly adjust the saddle, sit on the bicycle with both feet in the toe clips. The saddle is correctly adjusted when a plumb line from the center of the knee falls through the pedal axle of the foot when it is in the forward position with the crank parallel to the ground.
THE CUSTOM BICYCLE
many experienced cycling coaches we found no one who felt that a formula based on leg length should determine the proper seat height. Proper pedaling techniques are discussed in chapter 22 and the saddle height modifications required by varying pedaling styles are also covered. In the majority of cases, however, this method will be correct. As a further guide, the tip of the saddle will generally be approximately 6 inches from the top of the top tube if the frame has been sized properly. That will increase slightly for very tall persons and decrease slightly for short persons.
STEP 3—Horizontal saddle adjustment (front and rear)
This adjustment is one of the least understood in cycling. It is not used to correct for differences in top tube length or to make up for a handlebar stem that is too long or too short. The horizontal saddle adjustment is designed to accommodate varying styles of riding (dealt with in chapter 22} and differences in individual variance in thigh length. The height of the saddle corresponds to the overall length of the rider's leg—the horizontal saddle adjustment corresponds to the size of the rider's thigh. Some people have very long thighs and correspondingly short shins while others have very long shins and short thighs. In other words, the horizontal saddle adjustment is used to insure the proper angle of thrust of the leg.
To set up the horizontal saddle position, sit on the bicycle with both feet in the toe clips. Rotate the cranks until they are parallel to the ground. Have a helper drop a plumb line from the center of your knee of the forward leg. The plumb line should extend through the pedal axle.
Toe Clips
The length of the toe clip is determined by the length of the foot. Usually toe clips come in three sizes: small, medium, and large. You can identify the size of the Christophe toe clip by the engraving on the top. The small toe clip is marked Christophe D; the medium is marked Christophe; and the large is marked
BICYCLE SETUP
Christophe Special. A rough guide (variations are discussed in chapter 22) is:
Men's Shoe Size |
Toe Clip Size |
5-7 |
small |
8-10 |
medium |
11-13 |
large |
Generally, the toe clip is the correct size if the ball of the foot is directly over the pedal axle. Men's sizes are the only ones listed here since bicycle pedals are one of the many bicycle components that are not designed for women. If the rule of placing the ball of the foot is maintained on the smaller woman's foot (ladies' shoe size 6.5 or smaller), a small toe clip would be too big! The disadvantages are not immediately obvious; however, they are discussed in chapter 22.
When the toe clip is attached to the pedal (and the shoe cleat attached to the shoe), it should be adjusted so that the rider is pedaling slightly pigeon-toed. This results in a natural tendency to keep the knees close to the top tube which results in the most efficient pedaling motion and the least wind resistance. The reason for the pigeon-toed adjustment can be best demonstrated off the bike. Stand with both feet parallel, 8 inches apart, with the knees bent. In this position the knees will be slightly apart. If the toes are moved outward (figure 20-4B), the distance between the knees will increase. If the toes are pointed inward, the knees will come together. Obviously the feet should not be severely angled. If the toe clips are positioned too far out on the pedals, the rider's ankles will frequently hit the crankarms.
When the toe clips are inserted on the pedals, make sure that the buckle end is on the bottom so that the buckle does not rest on the side of the foot. Make sure that the strap has been twisted through the pedal (figure 20-5). This twisting eliminates strap movement each time the strap is tightened.
THE CUSTOM BICYCLE
Figure 20-4A: This position does not encourage the "knees to the bar" aerodynamic position.
Figure 20-4B: If the feet of a rider are pointed out, the knees will also point out. Obviously incorrect.
BICYCLE SETUP
Figure 20-4: Positioning shoe cleats and toe clips. The proper position for shoe cleat placement is best illustrated away from the bicycle. The cleats and toe clips should be mounted in such a way that the rider's knees remain close to the top tube when pedaling. If the feet of a rider are pointed straight ahead, the knees will also point straight ahead (figure 20-4A).
Figure 20-4C: If the feet are pointed in, the knees will point in. Although this is an exaggeration of the correct position, the cleats should be mounted to position the foot with the toes pointed slightly inward. The cycling shoe should not make actual contact with the front of the toe clip. It should be positioned .25 inch behind the clip.
THE CUSTOM BICYCLE
Figure 20-5: Positioning the toe clip and strap. The toe clip should be adjusted so that the toe of the shoe fits between the large opening in the front of the toe clip. If the cleats are mounted properly, the toe clip will be toward the inside of the pedal (note the adjustment slots where the clip attaches to the pedal). To eliminate toe strap slippage when tightening the strap, twist the strap through the pedal.
BICYCLE SETUP
Figure 20-6: Determining stem length. Some people believe that the length of a handlebar stem can be determined by placing the elbow on the tip of the saddle with the fingers extended.. . . This is not true. This measurement does not consider the overall length of the arm and body combined.
THE CUSTOM BICYCLE
Handlebar Stem (Extension)
The height of the handlebars is adjusted with the handlebar stem. Unless an "adjustable" stem is used (not recommended since they tend to slip under hard use), the length of the stem must be determined prior to its purchase and installation. The stem length is the variable corresponding to individual differences in upper body measurements.
Do not buy a stem based on the relationship of your arm length and the distance from the tip of the saddle to the handlebars (figure 20-6). While this is a good starting point, it does not take into account the individual differences in forearm length versus overall arm length or length of the upper body.
Determine the proper stem length by raising the handlebars to approximately 1 inch lower than the saddle (exception—racing position for short-distance events). With the hands on the handlebars (figure 20-7), and the elbows bent slightly, the rider!s nose should be approximately 1 inch behind the handlebars. Make sure you are sitting in a normal position on the saddle. This should be checked by someone who is standing away from the bicycle as explained in the saddle adjustment. If the plumb line from the nose is more than 1 inch behind the handlebars, the stem is too long. If the nose is ahead of the handlebars, the stem is too short. The handlebars should be adjusted so that the lower portion of the bar is slanting down slightly at the rear.
Now the bicycle is probably set up properly. But how do you check to make sure?
How to Check for Proper Positioning
Use an impartial observer to examine your position on the bicycle to see that the following rules apply to the way you are sitting on the bicycle.
Does the back have a smooth bend in the three basic handlebar positions (figures 20-7, 20-8, 20-9)? In no position should there be an acute bend in any area of the back. This sharp bend will usually result in back pain which can be virtually eliminated if the position is correct. Have your helper check each position while you keep your eyes looking ahead as if you were riding.
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