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Front Shock Disassembly - Cleanout

Note: you should follow the manufacturer's instructions for servicing your brand and model of front fork. Please see the manufacturer's web site for information, or do a web search for your specific fork. The instructions below are valid only for one specific type of fork, and are intended only to illustrate the servicing process.

If you ride in dust, rain, or mud, eventually your front shock will fill up with scratchy dirt. (It sneaks in through the vent holes in the boot -- the rubber accordion thingy -- and works its way between the sliding tubes of the shock.) If the crud isn't cleaned out, it will damage the shock. You might also want to take a shock apart to replace individual pieces, for example to swap elastomer to change the performance of the shock. If you only need to lube the wiper (the part that cleans the stanchion as it slides into the slider), see our page on Lubing the Wiper.

How you disassemble your shock absorbers depends on your hardware. Some are really easy. For example, the one just below on the left can be taken apart in about 60 seconds. (Just unscrew the plastic caps at the top, unscrew the bolts at the bottom, and unhook the brake cable, and it all slides apart!) Other front shocks are more complicated than brain surgery.

Left: Very common type of fork. The brake support arch is a separate piece of metal, bolted onto the lower tubes. Behind the dropouts, there's a bolt in a recessed cavity that holds the elastomer in place at the bottom. The top cap has two knobs -- the top one adjusts the tension on the elastomer, the bottom one unscrews the cap so the elastomer can slide out.

Right: Brake support arch is fused to lower shock tubes. No bottom bolt, but same mechanism at top of shock.

Left: Separate brake support arch, which must be removed to turn (silver) knob to release lower tube from upper. (At the top, the black cap is just to keep the dust out -- there is no adjustment or assembly mechanism here at the top.) Fork ends in dropout.

Right: Long tubes have a cross-support at the top of the steering tube. Cross-pieces clamp the top tube. Fused brake support arch. Separate tubes for rebound and dampening; one bottom has a bolt, the other has an adjusting knob.

Let's go to work on a sample shock. You won't need to disassemble as much as we have here, but our purpose is to show you how everything comes apart, so you can figure out what you need to pull apart on YOUR shock.

First, a bit of anatomy:

The front fork attaches to a tube (called a steerer) that inserts into the steering tube of the bike frame. This tube may be secured with bolts, or it may be welded solid. (The black ring is a bearing cup.)

On each side, the cross-piece attaches to a stanchion tube. On most bikes, you can remove these tubes, as shown here. On others (cheap bikes), the cross-piece and stanchion form a solid piece.

The stanchions slide into a bigger tube called a slider, which has a lubed wiper to keep dirt out. (It gets in eventually.)

On this bike, a top cap screws into the tube. This holds the elastomer in place, with an adjusting knob on top that can increase the downward force on the elastomer.

The slider (receiving) tubes may be a single unit, connected by the brake support arch. Or they may be individual tubes, with a separate brake support arch held on by bolts. The spindle onto which the brakes attach may be part of the arch, or it may end in a bolt that helps hold the arch onto the shock tubes. The photo above shows be brake-support arch and spindles being removed from a shock with individual sliders. (You usually will NOT have to do this to simply clean and lube the shock.)
OK, now let's take apart a sample shock for cleanout. (Pretend we haven't done anything yet.) Our bike is the first example above, an elastomer shock without recoil dampening, with a bottom attachment bolt and a screw-in top cap on top of the elastomer. (Your shock may be different. That's why we've shown you what some of the other stuff is, and how it's removed. For example, on one of the bikes above, you need to remove the brake support arch in order to open the shock.)
After dropping the wheel and disconnecting the brake cable, we unscrew the bolts from the bottom of each side of the fork.

After removing the bolt from the bottom, the bottom half of the fork (the sliders) falls away from the two smaller top tubes (stanchions). (Although the photo shows the brake support arch removed, on this shock you only need to disconnect the brake cable, and both lower halves slide off as a unit.)
We clean off the stanchion and anything that came out with it.

Now we clean out the inside of the slider, with attention to the wiper at the top.

(Note: We didn't have to remove the brake support arch to clean out this shock, but with other types you may need to.)

Now we unscrew the top cap from the stanchion and pull the elastomer units out. We clean the elastomer and the inside of the tube. We make sure the adjustment mechanism works freely.

Now we lube the adjustment mechanism and put the elastomer back.

We wash out the shock boot.
We lube the inside of the wiper, and any bushings within the slider. If the manufacturer has recommended a specific lube, use it. Usually, this will be a heavy slick grease such as Red Rum, Slick Honey, or even bearing grease.

Now we put the boot back onto the groove at the top of the slider, then slide the inner (stanchion) tube back into the lower half of the shock.

We put a little extra grease where the boot rides on the top of the shock, to keep dust out.

Now we put the bottom bolt back in both sides of the shock, and reattach the brake cable. Our shock is clean. 


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