The Anatomy of a Speedway Bike
Speedway bikes are simple, stripped down - but perfectly purposeful
Simplicity is extremely difficult to achieve.
While the apparent straightforwardness of the oval is one of speedway’s key appeals there are a raft of mechanical subtleties on a speedway bike that help achieve the zen like flow of the ultimate heat. These machines are some of the most focussed, purposeful bikes in motorsport – their stripped-down setup leaving little room for error or compromise.
In speedway the onus is placed firmly onto the rider’s machine-handling abilities and his knowledge of clutch and throttle control.
Gearing in speedway bikes is fixed through ratio displacement between the front two sprockets and the rear wheel sprocket. Depending on rider choice and track conditions the bike will be set up with a specific ratio. All gearing sprockets are connected to the bike for quick release, as they are often tweaked as the meeting progresses.
On cornering riders are hunkered high up and forward and so the seat is used just for a couple of seconds on the straight.
Centrifugal force drives the speedway bike into the slide while the left boot is extended in the corner. Foot rests, therefore are of course only needed on the right hand side of the frame.
Speedway bikes use a methanol fuelled 500cc engines which produce around 85 BHP. The major manufacturers are Jawa of the Czech Republic and GM of Italy. Modern bikes must adhere to strict weight limits, and use a ‘lay down’ configuration that helps produce a low centre of gravity.
Adjustment and jetting settings are made specifically for methanol fuel. Air filters often comes with a protective dust cover over the filter.
A cord attached to riders’ right wrists link directly to a kill switch located next to the throttle. The switch is spring loaded and when the cord is pulled away this closes the signal to the ignition.
REAR WHEEL MECH
Two adjustable nuts are attached to the centre of the rear wheel bolt. This helps align the rear wheel on the bike. The further back the wheel sits in the frame, the easier it is to slide the back wheel. This setting is the one used for beginners and novices. More experienced riders will set the wheel further forward for greater traction.
Modern bikes have adjustable front forks with shocks.
These are a requirement and are moulded and normally custom painted to order. A simple two-bolt system allows for quick changes if damaged.
Spring loaded and attached to the carb via a cable, the throttle is one of the key elements of the speedway rider’s focus. His sensitivity and knowledge of the throttle’s responses will define his success.
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