How To Remove Bike Fork

AMSOIL Tech Tips: How to Rebuild Dirt Bicycle Forks

In this video, we show you how to rebuild dirt cycle fork seals and bushings, and modify suspension fluid. How...

In this video, we show you how to rebuild dirt bike fork seals and bushings, and change suspension fluid.

How to Rebuild Dirt Wheel Forks

For this demonstration, nosotros're using KYB 48-ml air-over-spring (AOS) forks from a 2009 Honda CRF450R.

Common reasons for a fork-seal leak include bad bushings, which will cause the lower fork leg to move and cause an oil leak; dirt or droppings breaching the seal; or a rock flake or nick in the lower fork tube sliding by and ripping the seal.

Tools You Need

Owner'southward manual or other instructions for installing fork seals
Suspension fluid (at least two quarts for each fork)
Seals and fork bushings
Properly sized seal driver
Seal bullet to assist install the seals
Seal driver
Fork-cap hex wrench and fork-cap wrench
Torque wrench
Soft hammer
Screwdrivers
Picks
Nitrile gloves
17-mm and 19-mm sockets and ratchet
fourteen-mm wrench
Contact or brake cleaner
Drain pan
Graduated cylinder

Check Compression and Rebound Clickers

First, employ a standard screwdriver to determine the settings of the pinch and rebound clickers. Starting with the compression, turn the spiral clockwise and count the number of clicks until it's seated. Write downwards the number. And then, unscrew the pinch valve all the way until it stops.

Repeat the process with the rebound, which is ordinarily located on the bottom of the fork.

Drain the Suspension Fluid

Next, clamp the fork associates in a vise using a pair of soft-jaws and loosen the cartridge cap nut. Remove the fork body and tip it upside down to bleed the pause fluid into the drain pan.

Clamp the fork body into the vise and loosen the rebound-adjusting nut. In one case the threads are exposed and it has stopped moving, it'due south time to compress the spring. Employ a 14-mm wrench to hold the lock nut and the bottom of the fork lug. Remove the rebound-adjustment nut. It's important to pull the rebound-adjustment rod out and so information technology doesn't fall and go damaged.

Compress the jump and remove the wrench. Now, unthread the top and slide the fork body downwardly. You can now remove the cartridge. There should be a spring with it. Set everything aside for now.

Dirt bike fork rebuild Next, remove the dust seal. Use a small standard screwdriver and hammer to pop it out. Remove the small-scale retaining ring with a pick.

Remove the Seals and Bushings

At present, separate the lower tube from the upper tube. The oil seal, grit seal, retaining washer and bushings will be left on the lower tube. To remove the inner bushing, use a apartment-caput screwdriver to pry autonomously the slit and slide the bushing over the edge. Slide off the other bushing, retainer, oil-seal clip and dust seal.

Remove the tube from the vise and set everything on a table in the order in which it was removed. Remove the jump from the fork, the washer and the spring seat. Remove the O-ring, rebound adjuster and copper sealing washer. Clean everything with contact cleaner or in a parts washer. Dry all the parts with compressed air when yous're finished cleaning or let them drip-dry.

Next, remove the compression assembly and piston from the cartridge using the fork-cap hex wrench. Remove the pinch valve and prepare information technology aside in a make clean container. Drain the oil from the cartridge. While it'southward draining, inspect the compression assembly and complimentary piston for harm. Clean with Brake & Parts Cleaner that'south O-ring condom or a parts washer. Dry with compressed air.

Fill up the Cartridge with Suspension Fluid

Clamp the cartridge in a vise. With the pinch associates in a make clean container, add intermission fluid to soak the assembly and help remove air bubbling. Before filling the cartridge with fluid, tape the transfer ports closed with painter's tape. Pour in intermission fluid slowly to reduce air bubbles. Move the dampening rod slowly to distribute the fluid throughout the cartridge and dislodge air bubbles. Height-off the fluid to just below the threads.

Install the Pinch Assembly

Extend the dampening rod every bit far as it'll go. Remove the assembly from its container of suspension fluid and install it into the cartridge. Rotate the associates and install it at an bending to eliminate equally many air bubbles as possible. Somewhen it volition float in the fluid straight upward and downwards. Let it settle into the cartridge until it stops. Next, move the lower dampening rod up while applying light force per unit area to the assembly.

Drain Air from the Cartridge

Commencement by lightly belongings the compression assembly and pushing upwardly on the dampening rod. The pinch assembly will rise with the dampening rod. Eventually, it will stop. At that betoken, push button well-nigh 15 to xx mm farther and then fully extend the dampening rod, which will draw the associates into the cartridge until the threads bear upon. Tighten the assembly into the cartridge using the fork-cap hex wrench and a torque wrench.

Next, remove the cartridge from the vise and remove the tape over the transfer ports. While holding the fork associates over the drain pan, push the dampening rod to remove backlog fluid from the ports. Extract the dampening rod and repeat until the fluid is removed.

Bank check Dampening-Rod Action

Clamp the cartridge back in the vise to ensure it works correctly. Push the dampening rod until it stops. So, let it go. It should rebound smoothly with no fluid leaks at the seals.

Install New Fork Seals

Clamp the lower-fork tube in the vise. Inspect its surface for nicks or deep scratches. Utilise 400-dust emery textile or higher to sand anything you can experience with a fingernail. Always sand perpendicular to the fork tube.

Side by side, install the new fork seals and bushings. Place the seal bullet over the end of the fork tube. While wearing gloves, dip your finger in make clean suspension fluid and lubricate the fork tube.

Install the dust seal showtime. Side by side, install the retaining clip for the oil seal, so the oil seal. It helps to lubricate the within of the seal. Next, install the spacer and the new bushings.

At present nosotros're ready to install the outer spring tube. Lubricate the inside to ease installation and slide it onto the fork tube. Use a properly sized seal driver to install the seal. Rotate the outer tube while driving the seal to ensure it seats evenly. To know when it's seated all the way, utilise a flashlight to cheque if the seal is below the retaining clip. Now, install the clip. It should make an audible sound once it drops into place. Finally, slide the dust seal on.

Install the Spring

At present, it'south fourth dimension to install the cartridge and leap into the fork. First, install the O-ring and spring seat onto the cartridge. Make certain to inspect the O-ring and bushing condition prior to installation. Then, supercede the spring seat.

Install the Rebound Valve

Next, lesser out the jam nut on the dampening rod to provide space to install the rebound valve. To assemble the rebound assembly, outset by installing the sealing washer, taking intendance to inspect the O-band. Prior to installing into the fork trunk, install the spring washer. Next, install the spring.

With the fork tube mounted in the vise, install the cartridge assembly, guiding it between the bound until it bottoms out. Use the rebound-adjusting rod to guide the assembly every bit you push information technology into place. Finally, install the rebound-aligning rod. Tighten the assembly into the fork leg to the proper torque specifications.

Add together Intermission Fluid

Every suspension company will send a sheet with the suspension that specifies the correct fluid volume to add to the forks. When pouring interruption fluid, bending the fork and make sure the peak tube is all the fashion down so you tin can pour around the compression tube. One time you've added the fluid, slide the lower fork tube up and snug the top cap. Torque to the proper specifications.

Reset the Pinch and Rebound Clickers

The last step is to set the compression and rebound clickers to their original settings. Seat the clickers using a screwdriver, and so back them out the same number of clicks noted earlier.

For more Dirt Wheel Tech Tips, visit our Dirt Wheel Maintenance folio.