DIRTBIKE

116 | APRIL 2016 http://www.adbmag.com.au

THEBACKEND |

ADJUSTING 4CS FORK OIL

BASIC

HOW

TO

Forks contain oil which creates damping. You can change the characteristics of the fork by changing the height of the oil inside. If you increase the

oil height, then the fork will become slightly stiffer and more progressive. If you lower the height, then the fork becomes less progressive. All forks

have manufacturer’s specifications when it comes to oil heights but here is how to adjust the height easily on a 4CS fork.

1 REMOVE THE FORK

Firstly, you will need to remove the fork

from the bike. On some forks, it is possible

to adjust the oil height with the fork still

on the bike but, for the most accurate

measurement, remove it from the bike.

2 UNDO FORK CAP

Undo the top fork cap and slide the outer

fork tube down so you can reach the spring.

3 HOLD THE LOCKNUT

Take a spanner, place it between the coils

and hold the locknut on the damper rod.

4 UNSCREW THE CAP

Unscrew the top cap from the damper rod

and set it aside on a clean bench.

5 REMOVE SPRING

Slide the spring out of the fork tube and set

it aside. Be careful, as some oil will come

out on the spring and if you pull the spring

out too quickly you will wear the oil.

6 STEEL YOURSELF

With the fork compressed, slide a steel ruler

down into the fork tube until it touches the

oil, this gap between the oil and the top of

the fork tube with the fork collapsed is the

oil height.

7 SUCK IT UP

If you want to lower the oil height, take an

oil-level adjusting tool, such as the one

made by Motion Pro, and set it to the oil

height measurement that you are after.

Slide the tool inside the fork and use the

syringe to suck out any extra oil until you

reach your required oil height.

A simple version of one of these tools

can be easily made at home with a piece of

rubber hose and a syringe.