Peddling with gears
When you push down on the bike peddle the large front gears (sprocket) turns. This front gear makes the chain move (chain wheel). The chain moves a small set of gears (back sprocket called freewheel) on the back wheel. Every push of the peddle makes the back wheel turn 2-3 times.
With a bike gear, the larger the sprocket means lower the gear. The smaller the sprocket means higher the gear. Low gear is for easy pedaling. Good for uphill or into the wind. High gear makes you pedal slowly and helps go long distances.
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The type of gear that is in a bicycle is the Rack and Pinion gear. Back and front derailleur are used to change gears on a bike. The derailleur changes the tension on the chain and drags the chain into a different position.
Bike Gear Experiment
Question – How do different gear ratios on you bike affect your bicycling?
These are some of the experiments we did to see how bicycle gears work and how fast each gear is.
Test #1 Short distance (20 feet from dead stop)
(a) In its lowest gear (front gear less teeth than back gear) it took 4 seconds for the bike to go 20 feet.
(b) In its highest gear (front gear more teeth than back gear) it took 3 seconds for the bike to go 20 feet.
Test # 2 Long Distance (whole block from dead stop)
(a) In lowest gear it took the bike 7 seconds go a block. (b) In medium gear it took the bike 8 seconds to go a block.
(c ) In High gear it took the bike 9 seconds to go a block.
If you want to learn more about how bicycle gears work, here are some more tests you can do:
Test #3 Two bikes – one in low gear one in high gear to see which is faster.
Test #4 – Traction “pulling power” – which gear gives you the most pulling power ?
On the next page you will learn about how gears are used in our every day lives.