fork oil

A telescopic fork is a form of motorcycle front suspension whose use is so common that it is virtually universal. The telescopic fork uses fork tubes and sliders which contain the springs and dampers.
The main advantages of the telescopic fork are that (i) it is simple in design and relatively cheap to manufacture and assemble; (ii) it is lighter than older designs using external components and linkage systems; and (iii) it has a clean and simple appearance that bikers find attractive. Telescopic forks sometimes have gaiters to protect the fork tubes from abrasion and corrosion.
A more modern (and more expensive) version of the conventional telescopic fork is the inverted or "USD" (upside-down) fork.

BMW's patented telelever front suspension appears at first glance to be conventional telescopic fork, but the fork tubes contain neither springs nor damping. Instead, a wishbone and an inboard monoshock perform suspension duties, and the forks serve to locate the front wheel and control steering.

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