Bicycle Gears not to use

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Gearing allows you to maintain a constant degree of leg effort under such varying conditions as winds, hills and fatigue. Using gears in this manner may not make you go faster but you will use your bodies resources more efficiently. More info http://www.rbinc-sports.com

Developing a high cadence, how often you spin the crank arms per minute, is the key to efficiency. Most new comers to cycling spin at about 60 rpm. Experienced riders generally spin in the 80 to 90 rpm range.

To spin a high cadence and not exhaust yourself in the effort, you must choose the correct gear that corresponds with your strength and endurance. You must train your body to accept a higher cadence by increasing your aerobic ability.

Your strength affects what gear you choose to pedal at your chosen cadence. Closely linked is your aerobic ability to maintain that cadence over long periods. When riding with friends you may note some have the ability to climb hills in harder gears or maintain a constant high cadence without sign of exhaustion. Luckily our bodies respond well to training and repetition. To become better at maintaining a high cadence, ride at a high cadence until you are no longer comfortable at that level. Keep trying and your body will get better.

When confronted with a long set of stairs, do you choose to run up the stairs two or three steps at a time, risking exhaustion before you get to the top, or do you pace yourself and climb the stairway one at a time? It depends what you want to achieve. Cycling is the same. Using your gears you can ease up a hill in small steps or proceed with monumental efforts. Potential exhaustion is not the only drawback to low cadence. Low cadence/big effort cycling is very hard on the knees. Certainly, when you use an easier gear, as in climbing steps one at a time, you will not be going as fast, but you last longer.

Six points to consider about your body, cadence and efficient cycling.

    1. Aerobic Fitness – Spinning in an easy gear allows the body to use the aerobic metabolism for energy production. Energy stored in the body for this metabolic process are long lasting.
    1. Endurance – Pushing a harder gear will force the body to use the anaerobic metabolism sooner. This metabolic system is not as efficient with your bodies resources. There is only about 10 minutes fuel supply for this type of metabolism and results in the introduction of lactic acid in the blood stream. A build up of lactic acid in the muscles creates a burning sensation and impedes fatty acids from entering the blood for use during the aerobic metabolic process. Your liver will eventually make use of the lactic acid but it takes a while.
    1. Logic – You determine the effort to propel you from A to B. For a given distance, the more pedal strokes you make, the less effort required per pedal stroke and the less likely you are to fatigue.
    1. Comfort – Riding with a smooth, fast cadence will make your legs supple and relaxed instead of stiff and tired.
    1. Reserves – A fast spin keeps a reserve of power in your legs for when you need to sprint, out run a dog or climb a hill.
  1. Preparation – Developing a good spin is an excellent base for improved fitness. Smarter riding will lead to increased aerobic ability. Muscle strength will follow if you continue to challenge the threshold of your abilities.

Tips on Cadence

  • To develop a smooth fast spin, think ‘circles’ as you spin the crank arms.
  • Pull through the bottom of the stroke, like you were scraping mud off your shoes.
  • Keep the pedal force light and your cadence high.Occasionally count your cadence or monitor it with a bicycle computer.

Gear Selection – for people challenged by gear numbers and terminology

  • Effort becomes ‘easier’ as the chain gets closer to the frame.‘Easier’ is synonymous with ‘low’ or ‘lighter’ gearing.

Use easier gears for uphill, headwinds or fatigue.

  • AND effort becomes ‘harder’ as the chain moves further from the frame.‘Harder’ is synonymous with ‘high’ or ‘heavier’ gearing.

Use harder gears for tailwinds, downhills and speed.

GEARS INCH FORMULA & CHART
Adapted from TCCC CB Instructors Manual

What good are gear calculations?

Once you know how to use your gear selector, you know how to find easier or harder gears. If your ‘easiest easy’ and or ‘hardest hard’ does not suit your cycling style, calculating the ‘gear inches’ will allow you quantify your needs. Calculating ‘gear inches’ of your entire setup can help you identify unsuitable gears, gaps, repetitions and the shift pattern of your gearing.

Unsuitable Gears – as described above, decrease your enjoyment of cycling. Gears are not low enough to allow you to get up hills easily, or not high enough to allow you to pedal downhill with force.

Unsuitable Gaps – are found, between your high and low gears. If a selected gear is too hard, but the next one is too easy, there is either a gap in gearing or you are not following the shift pattern of your setup.

Repetitions – your setup may have duplicate gears, or a gear inch so similar to another gear they are essentially the same. Look for gear inches that vary at least three percent.

Shift Pattern – Your setup contains one linear shifting pattern to go from the highest to the lowest gear. Use the following formula and Table II to illustrate what your linear shifting pattern is. Maybe the gear you thought was missing is close by on the another chain ring.

To determine gear inches you must know the diameter of the bicycle wheel, the number of teeth on the chain ring at the front, and the number of teeth on the rear cog.

gear inches = (wheel diameter in inches)(# chain ring teeth)/(#rear cog teeth)

Touring Bike Example: 27 inch wheel (~700C) with a 52T chain ring and 13T rear cog. 27 X 52/13 = 108 gear inches

Mountain Bike Example: 26 inch wheel with a 46T chain ring and 13T rear cog. 26 X 46/13 = 92 gear inches

Typical Gear Inches Chart to determine Shift Sequencefrom Easiest (1) to Hardest (12) gears to spin.

42T Front Chain Ring

52T Front Chain Ring

Rear Cog Gear Inches Shift Sequence

Gear Inches

Shift Sequence

13T 87.2 Avoid Using* 108.0 12
14T 81.0 8 100.0 11
15T 75.6 6 93.6 10
17T 66.7 4 82.6 9
19T 59.7 3 73.9 7
21T 54.0 2 66.9 5
23T 49.3 1 61.0 Avoid Using*
*Note this table lists two combinations to Avoid Using. Extreme combinations wear the chain, chain ring and cog prematurely. As well, these combinations are hard for the derailleurs to manage. You may here rubbing at the front and, at the rear, the chain may skip due to excess chain slackness.
Most people cannot feel a difference of less than 3 gear inches making gears 4 and 5 essentially the same.

My Bike’s Gear Inch Chart and Shift Sequence

Small Front Chain Ring

Medium Front Chain Ring

Large Front Chain Ring

Rear Cog Gear Inches Shift Sequence

Gear Inches

Shift Sequence

Gear Inches

Shift Sequence

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