| Mountain bike gears are continually becoming | | | | can continue your pedaling at a consistent pace, |
| more and more complicated and intricate. | | | | no matter what terrain you are on or what your |
| Today’s bikes can come with up to 27 | | | | speed is. |
| gear ratios. It is common for a mountain bike | | | | A typical mountain bike that has 27 gears will |
| today to use nine gears in the back and three | | | | have six gears so incrementally close to the other |
| sprockets of different sizes in the front for gear | | | | that you will not be able to determine that there |
| ration production. | | | | is any difference between the gears when you |
| Why so many gears? The most common reason | | | | change them. |
| is that a large number of gears allow a rider to | | | | Most mountain bike riders decide to choose a |
| pedal at the same pace no matter what terrain | | | | gear system with a front socket that is suitable |
| that he/she is on. This can be understood better | | | | for the slope or terrain that they usually ride on |
| if you think about a bike that just has one gear. | | | | and they stay with this choice, even though it |
| Every time you turn the pedals one full turn, then | | | | may be more difficult under a heavy load to shift |
| the rear wheel also turns one full turn, too (1:1 | | | | the gears. This is purely a personal decision, but it |
| gear ratio). | | | | is simpler to shift between gears when the rear |
| For example, your back wheel is measured at 26 | | | | socket, rather than the front one. |
| inches. If you pedal one full turn, then this would | | | | When you are pedaling uphill, then you will find |
| mean that your wheel moved 81.6 inches. If you | | | | that it is much better to choose a sprocket that |
| are riding at 50 RPM, then you will be able to go | | | | is smaller on the front and then shift gears with |
| 340 feet per minute. This means that you were | | | | the nine gears that are available on the rear. If |
| going 3.8MPH, which is equivalent to walking speed. | | | | you are more speeds on the rear sprocket, then |
| This speed is great for going up a hill that is | | | | you will find that it is much more efficient to ride. |
| steep, but it is not a good speed for flat ground | | | | Mountain biking needs gears so that you can keep |
| or racing downhill. | | | | an overall speed going. If you didn’t have |
| If you want your bike to go quicker, then you will | | | | gears, then you would find it difficult to build up |
| need a different ratio. If you want to reach a | | | | any speed and you would find it nearly impossible |
| speed of 25 MPH downhill using a 50-RPM | | | | to pound your pedals for extra control. Gears help |
| cadence, then you will need to have a 5.6:1 gear | | | | to move the pedals and enable you to gain that |
| ration. If you have lots of gears on your bike, | | | | speed. |
| then you will be able to get that ratio so that you | | | | |