Want to fiddle with the suspension on your track bike? Firstly, check your tyre pressures and make sure they're spot-on. Then identify whether you want to alter your suspension at all. If the bike feels fine, then don't touch it. But, if you want to make some changes then this guide should help you identify what adjusters do what and how they affect your bike. The rule is to set up your static sag and then make one adjustment at a time, ride the bike and see what difference it makes. Always make a note of the standard settings, so you can easily go back to them if you feel you're going in the wrong direction.
What is...?
Static sag: ...is the free play in your suspension between maximum extension and a normal resting position at a standstill. Lift the back of the bike as far as it will go without the rear wheel leaving the ground and measure between the wheel spindle and a mark on top of the tail unit. Then allow the bike to return to its normal position and measure it again. The difference is your static sag. Ideally you want between 20-25mm. Repeat this process with the forks to find your front sag. Remember, more preload means less sag and vice versa.
Preload: ...is an amount of tension set in a spring before a load is applied. It's the most basic suspension adjustment found on motorcycles.
Rebound damping: ...is what controls the speed of your spring's rebound or bounce back after being compressed. Without it, the bike would bounce you out of the saddle over bumps, while too much rebound and your springs won't have time to recover between the bumps and the bike will squat down.
Compression damping: ...controls the speed at which the springs compress under load - that means during braking, accelerating and hitting bumps. Too much and it will feel harsh, too little and your bike will see-saw from one end to the other.
Where are the adjusters?
At the front...
...of the bike you have a pair of forks. Preload adjusters sit at the top of the legs and generally require a 14mm or 17mm spanner. Adjustment is by turns and measured by rings marked on the exposed part of the adjuster. The more preload you wind in, the fewer rings are left showing. Make sure you adjust them together so the settings are the same. Front rebound adjusters will be on the top of your fork legs - they're the flat-headed screw nipples that poke out of the preload adjusters. These are measured by turns and many will make an audible click when you turn them. Compression damping is adjusted via screw heads like rebound, but the adjusters themselves are found at the base of the forks, by the wheel spindle.
At the back...
...preload is put on at the back via a collar normally on top of the spring on your shock absorber. Sometimes the preload collar is at the base of the shock so do check. Adjustments are made with a C-spanner. Compression damping can be altered by a flat-head screw adjuster at the top of the shock body, while the rebound adjuster can be found at the base of the shock, this has another screw-type adjuster.
Please note: this general advice applies to motorcycles being used on a closed circuit. Before adjusting the suspension on your road bike please contact your local dealer for advice.
