FORGOTTEN MOTOCROSS TECH: SPLIT REAR SPROCKETS

Motocross history is filled with examples of creative ideas that were heralded as groundbreaking, but, because of the rapid rate of change in development, sank into the swamp of forgotten technology. Although some are best left abandoned, others were truly innovative (if not ultimately successful). MXA loves to reveal motocross’ tech trivia. Do you remember this idea? Split rear sprockets.

At first glance, the idea of a split rear sprocket seems stupid. Yet, the concept keeps resurfacing every decade or so. Are you old enough to remember the overlap sprockets that came on Harley-Davidson Bajas and Husqvarna 400s back in 1972? They allowed the rider to turn a 34-tooth sprocket into a 48-tooth sprocket by bolting an extra ring of teeth onto the stock sprocket. The split sprocket was supposed to make gear changes easier.

In the 1980s, Sidewinder sprockets introduced the Double Cross split rear sprocket. It consisted of a conventional sprocket that was cut in half and joined together on the rear hub with interlocking jigsaw tabs. The big sales pitch for the two-piece design was that it allowed gearing changes without having to remove the rear wheel from the bike. The Double Cross was not a success because most riders couldn’t see the benefit of the time saved by not having to remove the rear wheel (after all, it was only one nut and the rear axle).

That didn’t stop Slater Racing from recycling the split-sprocket idea in 2012 with its EZ Sprocket. It was virtually identical to the Double Cross sprocket; however, it still couldn’t convince any motocrossers to embrace the concept. Obviously, the strength of the split sprockets caused concern, especially on Supercross-style tracks, where hard landings really torque a sprocket. When this idea returns in 2030, it will still be considered an oddity.