Dirt Bike Suspension -- Basic Tips
As always, a good shop manual is your best source of information when working on your dirt bike, and most have detailed information on the suspension. If you misplaced or lost the manual, here are a few basics you should take care of before starting any tuning.
Bleed your forks regularly. Most of the time this is done with a small bleed screw in the top cap. Let out excess air after every ride or race. Make sure you do this without any weight on the front end – and don’t forget to tighten the screw when you’re done.
The oil in your forks and shock gets contaminated over time and will affect your dirt bike suspension's performance… so change it regularly.
Clean components regularly, with LOW pressure water. Pressure washing any part of your dirt bike can force grit and water in – this can be especially harmful when it involves your suspension.
Inspect every moving part for wear, and make sure all the fasteners and connections (nuts, bolts, welds, duct tape, etc) are tight and solid.
Aren’t sure exactly how much your suspension travels. To find out before you do any tuning (and to check afterwards) put a thin cable tie around your fork leg or shock shaft. When the suspension travels it will move the tie so you can see precisely how far the suspension is compressing.
Keep the threads on the body of the shock lubricated so the spring adjuster nut and locking ring can move freely when it comes time to make adjustments.
Look for pitting and scratches on fork and shock shafts. Light cuts or scratches on your fork legs can be smoothed out with extremely fine grade wet sandpaper (but you may want to let a pro take care of that).
Dirt and grease can accumulate under the rebound rubber/bottoming cone on the shock absorber shaft. Clean under it.
Make only one change at a time, to one component at a time, and make them very small changes.
Record the settings you have BEFORE you start any adjusting. That way, if things get really messed up, you can always go back to square one.