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Change Fork Oil

How to Change The Fork Oil In Your “K” Bike

By Tom Coradeschi

Rene.Miranda@eng.sun.com wrote:
>Do you chaps perform your own front forks maintenance? I had it understood
>that some sort of ‘special tool’ is required to take apart the front
>forks, change forks seals, etc. Would you be so kind as to briefly describe
>the main steps taken to do the fork maintenance, (ie., unmount front wheel,
>unbolt left/right you-name-it, etc), and would this be transferrable to a
>K-bike as well? Thanks in advance for your input.

Changing fork oil and such is trivial, Rene.

On a K-bike, you pry off the plastic caps from the top of the fork tube and remove the capscrew in the top of it (you’ll need slip-joint pliers or a big wrench to keep the plug from rotating). Then you remove the leetle bitty bolt from the fork slider. It’s on the back (ie, facing the engine) below the brake caliper. Takes, ummm 8 mm wrench, I think. Pump the forks a few times to expel all the old oil. You did remember to put a catch pan underneath with a piece of cardboard to keep the rotor, wheel and tire dry, didn’t you? (You will next time:-}) Replace the itty bitty bolt. Get your graduated cylinder out and refill the forks from the top with the appropriate volume of the appropriate weight of the appropriate oil. That’s it! The whole job ought to take no more than an hour the first time, and progressively less each time after that (this should be annual maintenance, IMO).

Jon Diaz adds:

The only things I’d like to add to Tom’s instructions is that those screws at the bottom of the fork should be installed with great care and MINIMAL torque. Use you 10 mm wrench from your tool kit and gently tighten that screw. Even what seems like no torque holds them in just fine. I always use new crush washers but they probably aren’t necessary all the time.

Also, cover you rotors with aluminum foil to keep any fork oil from coming in contact with your braking surface. While it is easy to wipe the rotors off afterward, there is always the possibility that oil might sit in one of the slots in the disc and not be removed during your wipedown. Cover them to be safe.

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