Buell Xb9r Firebolt Chassis Rear Wheel
Occam's Razor: Buell XB9R Firebolt Road Test
In order to more easily change gearing to suit various tracks, the Hal's bike uses chain rather than belt drive. Because the bike has such a short swingarm that sits at a steep angle, chain tension varies substantially and an idler sprocket is used in place of the stock belt tensioner. Note also in this picture the braced swingarm (modified with chain adjuster) and the carbon fiber duct for air to exit from cooling the rear cylinder head.
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