The MTB drivetrain converts the power and velocity provided by the rider to the rear wheel of the mountain bike. The cyclist can choose the best gear ratio of it MTB drivetrain in order to adapt the torque supplied to the rear wheel according to the profile of the ground.
Components of MTB drivetrain :
A MTB drivetrain is made up of several gears which can be chosen by the rider. This variation corresponds to a change in the MTB's gear. You will find in our article "Table and calculation of a gear or bicycle development" the definition of a gear and its calculation formula.
The parts that make up an MTB drivetrain are the shifters which are controls attached to the handlebar and operated by the cyclist, the sprockets cassette attached by a freewheel to the hub of the rear wheel, the crankset made up of cranks and on which the pedals are fixed, the chain which transmits the force and movement of the crankset to the MTB cassette, the derailleurs which move the chain on the MTB chainrings and sprockets of the cassette.
The MTB drivetrain has evolved a lot over the last thirty years, in fact, at the end of the 80s, it consisted of 3 chainrings and 7 or 8 speed, then 3 chainrings and 9 speeds at the end of the 90s and the early 2000s then with the arrival of the 10-speed versions the small chainring was removed to keep only intermediate and outer. In the 2010s, the 11-speed was developed and only one chainring was retained.
The advantage of keeping only the sprockets and a chainring is to be able to improve the ground clearance of the mountain bike, to reduce the weight by removing the left shifter and the front derailleur. This evolution was made possible thanks to an improvement in the flexibility of the chain and a change in the number of sprocket teeth in order to keep the same gear ratio values as with 3 chainrings.
The MTB shifter(s) :
MTB shifters are levers that operate the derailleur of the MTB drivetrain, each impulse corresponds to a position of each derailleur in relation to the sprocket cassette and the chainrings. These controls can be mechanical with cable or electric.
It is fixed on the freewheel of the rear wheel hub, it consists of a set of sprockets on which the chain moves.
MTB crankset :
It consists of chainrings on which the chain moves, pedals which the cyclist supports and a bottom bracket containing bearings, fixed in the frame of the mountain bike.
MTB chain :
It transmits torque from the chainrings to the cassette sprockets.
MTB derailleurs :
These are actuators which move the chain on the chainrings and sprockets of the cassette. Their operation can be mechanical or electrical (shimano). The MTB rear derailleur also has a chain tensioner function so that it is always in contact with the teeth of the chainrings and sprockets.
MTB drivetrains brands :
The designers and manufacturers of components for the drivetrain of an MTB are few, in fact, Shimano is a Japanese manufacturer which dominates the market with a very complete offer and intended for all levels of practice, Sram is an American manufacturer which offers efficient and innovative MTB drivetrains. Microshift is a Taiwanese brand created at the end of the 90s, it offers technically simple and reliable solutions.
Checks of the components on second hand MTB drivetrains:
All used parts available in our shop have been cleaned and checked for functionality. All the bolted parts of the derailleurs, shifters and crankset have been checked. Based on our observations, their condition is rated from 0 (bad for parts) to 10 (new in its packaging).