How to determine the number of speeds
The nominal number of speeds is determined by the combinations of the front and rear of the stars. For example, if the bike stars 10 rear and 3 front, the nominal volume is equal to 30, and if the back 9 and then 27. However, there is one caveat — the actual number of speeds that can be used will be less. This is because due to misalignment and incorrect chain tension you should not use all possible combinations of stars.
Optimal switching speeds
In order to avoid tilting, and jump-out circuit is recommended to switch the speed as follows:
• The first front star running back with the stars in the combinations 1-1, 1-2, 1-3 and 1-4.
• The second chainring works with back stars in combinations 2-4, 2-5, 2-6 and 2-7.
• The third chainring works with back stars in combinations 3-6, 3-7, 3-8 and 3-9.
The result is that the bike with three front and nine rear stars nominally has 27 speeds (3 x 9=27), but in fact it is used only 12 speeds. And that's enough to travel through the terrain with any relief.
It is worth noting that to adhere to this scheme is entirely optional, but when using the optimal combinations of the shift of stars is significantly reduced chain wear.
How to shift gears
When riding against the wind, the sand, clay, wet mud, or uphill, you need to "dump" forward gear. Then it will be easier to pedal, to maneuver and gain speed.
The first forward gear is optimal for lifting, if you don't want to put much physical effort. The second transfer is suitable for small UPS and driving drogam. The third forward gear (the big star), it is recommended to switch while riding around the city. While reverse gear is switched in accordance with the above scheme of switching speeds.