The Pugsley frame has horizontal rear dropouts with a derailleur hanger. You can set it up with derailleurs or an internally geared hub, or set it up as a singlespeed or fixed-gear. This isn’t just a nice option. In certain situations, extra weight and the potential for a complex part to fail isn’t just a pain. It can be deadly serious business. The stock fork accepts a 135mm rear mountain hub, just like the frame. This makes it easier to install and remove the wheel (a big tire on a big rim benefits from a wide opening), but more to the point also allows front and rear wheel interchangeability. This means you can have another full gear cluster, a singlespeed or a fixed-gear wheel option should something go wrong with your freehub body or derailleurs. In other words, it’s one more option for getting you back out from whatever situation you’ve gotten yourself into.
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