Just wanted to share this

WOW! What's going on here? Looks intricate.

hd reynolds said:

[font=MS Gothic]Really sick! The Killer B Race Link[/font]
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But what is it?! 🙂

What's wrong with the standard chainring/cog setup? That looks cool and all, but I guess I'm missing what the point of the intracacy of it all is.

This is an example of a jackshaft system. Its purpose is to eliminate the feedback to the pedals from suspension action. The long tube going from the rear disc brake mount to the suspension mount helps eliminate brake jack, which occurs when the rear brake is applied and effects the rear suspension by rendering it "locked out" due to the forces of the brake on the suspension. Another slight advantage is the clearance of the chainring which lessens the chance of a chainring being damaged or bent. The system has a love/hate relationship with the riders I know. Those who love it, swear by its advantages. Those who hate it are of the "the more complicated it is, the more likely something will go wrong" camp. I have rode this kind of bike and must say there was no feedback through the pedals even on the roughest terrain. Though the feedback on a well engineered FS MTB has never really bothered me to the extent that I have to run out and buy the more expensive jack-shaft bike.

graphixgeek said:

This is an example of a jackshaft system. Its purpose is to eliminate the feedback to the pedals from suspension action. ...

Very cool, whether it's worth it in terms of weight or drivetrain losses is hard to say, but cool that someone's pushing the envelope. John Howard used a jackshaft system for his bicycle landspeed record a while back. His need was different, for the gear ratios he needed to break 150mph (behind a serious drafting machine on the Bonneville Salt Flats) his chainring would have dug a trench in the ground (and sawed off his right leg I suppose). So he used a jackshaft to get the gear ratio in two steps and ended up with big but reasonable chainrings.