As more BMXers began to ride mountain bikes and more MTBers wanted to perform ever more extreme and more BMX-like tricks a specific style of bike was developed to suit. Jump bikes blend the simplicity and smaller frame of BMXs with the rough ground capabilities of mountain bikes.
The result is a small, tough framed bike with either 24 inch or 26 inch wheels. The types of components can vary hugely with anything from single speed, single brake, rigid forked, steel framed 24 inch wheel bikes, like the popular DMR Transition all the way through to aluminium, suspension framed, disc brake and suspension fork equipped, 16 geared, 26 inch wheel bikes, like the Kona Stuff.
The more MTB style jump bikes (like the Kona Bass) are also used as and sometimes referred to as 4 Cross bikes. 4X is similar to BMX racing but with a maximum of 4 riders at a time racing on a beefed up, more off-road style course of jumps, berms and sometimes rocky sections. The bikes used for this are usually lighter weight, geared jump bikes with suspension forks with 100-150mm travel. Very few ‘off the peg’ 4X bikes are available so most people simply use the MTB style jump bikes like the Charge Blender and Mongoose Fireball.
Bikes like the DMR Transition and Specialized P1 are closer to the BMX end of the spectrum and their use reflects this as they are used everywhere that BMXs are; dirt jumps, skate parks and streets (urban riding). Their BMX-like simplicity makes them tougher and harder wearing.
These bikes are tough but not invulnerable – they will withstand their intended use but not abuse and will need to be maintained like any other type of cycle.
In general, both dirt jump and urban bikes are small and burly hardtails with tough components that can take the abuse of jumping ramps, skate parks, urban walls, ledges and concrete blocks.
Jump bikes typically have suspension forks with varying lengths of travel between 80-130mm depending on the rider’s style. These forks are similar to mountain bike forks but are generally stronger with thicker posts. Riders that do more urban or skate park riding often like shorter travel forks, while riders who like to ‘huck’ and do huge gap jumps often like longer travel forks, but it really doesn’t matter as long as they are strong.
These bikes can be used with 24″ or 26″ wheels, although some frames are made specifically for one or the other. These bikes are often ridden as single speeds bikes for simplicity but again some come with gears depending on the rider’s preference. Usually frames are specially designed to run either with or without gears and cannot switch between the two.
Many top riders have now become professional athletes and perform stunts and jumps in events and competitions all over the world.
Notable riders include NS bikes’ Martin Soderstrom and Sam Pilgrim who use the NS Majesty frame. The Athertons use titanium Commencal Absoluts for 4X races and a host of talented riders such as Sam Reynolds and Olly Wilkins ride DMR bikes. Prices range from around £200 to £1,900.
April 13, 2012 Bike Guides