oldtimers

							                                Updated Old-timers


                                  Mountain Bikes

Many inventors contributed to the history of the bicycle by developing human-
powered vehicles. The documented ancestors of today's modern bicycles were
known as push bikes. The so-called draisine was invented by the German Baron Karl
von Drais in 1817. It is regarded as the prototype of the bicycle. Its rider sat on a
wooden frame supported by two in-line wheels and pushed the vehicle along with his
feet while steering the front wheel. Since then, many innovations were necessary to
develop modern bikes for different demands, like riding up steep tracks with big rocks
and high roots.
Mountain bikes (MTB) are particular bikes for riding in mountainous country. They
have special features. MTB development has included an increase in gearing, up to
27 speeds, to ease climbing and rapid descents; as well as a wide handlebar for
better control; big pedals for better grip; brake discs for a better brake power; a more
stable frame for more safety; a shock absorber for the protection of the spinal discs;
no splashguards to prevent that something can catch in it; deep tyre profiles for a
better grip; a big rim for a better robustness and a wheel diameter of 26 inches for a
better mobility.
Mountain bikes perform in different ways like: All-mountains (AM): With an all-
mountain-bike you can easily start tours as far as a so called transalpine. The weight
ranges from 12 to 15 kilograms. Cross country (XC): They are made for racing on
an easy terrain like forest tracks but not for downhill. They are lightweight
constructions below 12 kilograms. Downhill (DH): It’s only for wide jumps and
downhill racing and has no gears and a very firm frame. Enduro: They are a mix of
all-mountain-bikes and free-ride-bikes. Uphill you can’t ride them comfortably but they
even perform well on downhill tracks. The weight ranges from 14 to 18 kilograms.
Freeride (FR): Freeride bikes are downhill bikes, which are suitable for riding up
steep tracks with big rocks and high roots. You can’t really drive uphill with them
because they are too weighty. Their weight ranges from 16 to 22 or even more
kilograms.
Based on suspension, mountain bikes can be classified into four categories:
- Fully rigid: A frame with an inflexible fork and fixed rear, no suspension.
- Hardtail: A frame with a front suspension fork and no rear suspension.
- Soft tail: A frame with small amount of rear suspension, realized by flex of the frame
instead of pivots.
- Dual or full suspension: A front suspension fork and rear suspension with a rear
shock and linkage that allows the rear wheel to move on pivots.

Recommended Link:
http://en.wikipedia.org/wiki/Mountain_bike
http://en.wikipedia.org/wiki/Bicycle