Spinnaker Seal Replacement Tutorial

Explanations and practical tips for self-service your motorcycle fork

Steps to Disassemble, Empty, and Replace Fork Seals

Any moving part, such as a motorcycle fork, as well as the two main tube and shell parts, are subject to restraints and wear more until they no longer fulfill their function. This is especially the case for the part that seals the tube and fork shell, I called the lip seal, also called the spinnaker seal.

In addition, impurities and insects build up over time in fork tubes and can damage the fork connections. Severe shock in a pothole or on the back of a donkey, poorly rested wheel lifters can also suddenly cause these joints to wobble (or rather an explosion ...). Even if there are only two rubber seals, they are very important for a good motorcycle performance. If your fork tubes are greasy when you recently cleaned, this is a sign. The joints are probably dead. It can become dangerous on the road because oil may leak on the brakes!

Changing the fork seals

Replacing the spinnaker fork seals is not necessarily easy. However, operation is necessary to maintain good circulation and prevent oil leakage. Of course, the more adjustable the fork, the more difficult it is to disassemble.

Changing the spinnaker seal costs between 120 and 200 euros at dealerships or motorcycle mechanics. So we might be tempted to do it ourselves with a good economy. But be careful, you have to follow these steps well and be a little handyman.

Spinnaker seals are sold with or without a dust cover. If we can restore the original ones from scratch, it is always better: sliding parts, even less fragile than a spinner, also wear out, let's face it. For classic forks, some motorcycles and accessories offer small, inconspicuous deflectors. They allow you to spare as many joints and a specific area of ​​the fork tube as possible by attaching them to the shell. Bier offers them in his catalog for about 9 euros, for example.

Caution: Please read your fork settings before disassembling

Write down your plug settings, even if you go through a pro. Your servant went through another quick fork service twice. For 2 times, different settings were imposed on each shell, and especially completely stupid and, to say, the least dangerous settings in the case of rhythmic driving. Know what is going on on your motorcycle and know how to get back in the absence of interference that has no relevance or professional conscience. In mechanics, do not confuse speed and draft.

Fork components

• a tube
• shell
• Spring
• dust cover
• spinnaker seal
• cap
• tubular rings
• Shock absorber BTR
• rod shock absorber
• Washers
• spacer
• stop clip

Tutorial: Replace Spinnaker Seals in 6 Steps, Disassemble Fork

1. Cleaning fork oil and recovering used oil

2. Disassemble the fork arm

Find all the steps to dismantle and clean up the oil in our Clearing a Fork Tutorial

Fork drainage

After these steps have been taken,

3. Disassemble the shells

The fork contains many elements, often intertwined. Especially if it offers adjustment possibilities (relaxation, compression). Each shell often has a washer, gasket, nut, o-ring, stem, and plunger rod, not to mention the spring that is needed to make it work.

Before separating everything, pay attention to the order of the parts for reassembly. Photography is a plus.

Pay attention to the parts of each plug

Remove the dust cover, for example with a flat screwdriver.

We remove the dust cover

Remove the spinnaker pin, always with a flat screwdriver

Spi Seal Retaining Clips

4. Disassemble the inside of the plug.

A special tool may be required: it is often held at the bottom of the fork. Then we go through the plug. In the absence of a specific tool, a high torque air gun may be required.

Untie the fork tube and restore the elements (inner fork body).

Remove the fork tube by pulling it out. Resistance is normal: you must go through the "hidden" one formed by the spinnaker seal.

Remove the spinnaker seal from its body.

5. Install a new Spinnaker seal

Place the new spinnaker seal on the fork tube by sliding it over the shell. To do this, you need to lubricate it well. Think fork oil or WD40.

Be careful. To avoid hitting the lips of the latter, protect the end of the fork tube through which the spinnaker is inserted with tape.

Protect the fork tube with tape

Get off the spinnaker and go to its accommodation.

Two solutions for sealing it:

- an inner tube that is larger than the fork tube and an outer cross section lower than the shell and the old spinnaker seal, which acts as a buffer between the two elements when moving back and forth.

Or

- tool for assembling Spinnaker seals. It consists of two semicircles and a gripping part, its diameter is adapted to the diameter of the shell. It closes on the latter and is used to "buy" a new seal by moving this moving mass up and down.

Spinnaker "tightly".

6. Assemble the plug

Partially reassemble the plug after re-disassembly operations. Do not put the spring or the top back.

Vertical shell, pour the specific and specified volume or height of fork oil into the fork tube.

a professional tool to make sure you put in the right amount of oil? Syringe with graduated shaft, caliber and support. It is also possible to check the height of the oil in the fork shell using a graduated "diver" rod and ring that will be placed on top of the fork tube. This ensures that the volume is neither too large nor too small. Lack of oil and loss of motorcycle handling. This risks freezing and loss of trajectory accuracy, in addition to less good cushioning.

The oil pressure is overloaded, and it will be too "hard", threatening the spinnaker joints.

For more information, read the Clearing a Fork tutorial.

Maintain your spinnaker seals

One can simply maintain spinnaker seals with a small tool called Seal Mate, proposed by Motion Pro and distributed by BIHR. Its price: 12,50 euros

Remember

• Observe the required amount of oil
• Pay attention to the viscosity of the required oil. While 10W is standard, sports cars require 5W (e.g. CBR 1000RR). A good brand of oil is a plus: they perform and age better under constraints.

Not to do

• Do not check the settings provided by the "pro". It's important to check all the settings your plug suggests when you get back on the road. 2 times I went through a professional ("fast" service), 2 times he put me different settings in each shell and especially completely stupid settings. Be careful, danger.
• Poor tightening of casings
• Poor tightening of the brake calipers
• Put the oil too hard, hoping to improve the behavior of an overly flexible fork. Better to play in the front settings or change the spring or fork.

Tools

• Oil
• Spinnaker Seal Fork
• Key to the socket and socket,
• flat key,
• flat screwdriver,
• electrician tape,
• spinnaker print "ccup",
• air gun, electric gun,
• lift, blemish, jaw and enough to recover contaminated oil,
• measuring glass and / or graduated strip or oil height sensor,
• crutch or support to stabilize a motorcycle without a front wheel