from a while ago...
http://www.ukgser.com/forums/showthread.php?t=42530
and
just a few things to look out for
Rebound damping
*Rear suspension
Too much rebound damping can cause:
- The rear "jumps" on the bumps instead of following the surface.
- The rear "jutters" under braking.
- It holds the rear down with the result that the bike will understeer!
- It can cause overheating in the hydraulic system of the shock absorber and make it fade, in other words, it will loose damping when hot.
Too little rebound damping can cause:
- The rear "tops out" too fast under braking, causing the rear wheel to jump
- The bike feels unstable.
*Front suspension
Too much rebound damping can cause:
- Oversteering!
- It will give poor grip of the front tyre.
- It feels like the front wheels will tuck under in corners.
Too little rebound damping can cause:
- Understeer!
- The front can feel unstable.
Compression damping
Rear suspension
Too much compression damping can cause:
- The rear wheel to slide under acceleration .
-It can give a harsh ride over bumps.
Too little compression damping can cause:
- The rear wheel start to bump sideways under acceleration out of the corner.
- The bike will squad too much (rear is too low), that will cause the front to loose grip.
Front suspension
Too much compression damping can cause:
- Good result during braking.
- Feels harsh over the bumps.
Too little compression damping can cause:
- Strong diving of the front.
Spring ratio
Rear
Too hard spring ratio:
- Gives easy turning into corners.
- Makes the rear feel harsh.
- Create poor rear wheel traction.
Too soft spring ratio:
- Gives good traction in acceleration.
- Creates understeer in entry of corner.
- Makes too much suspension travel which will make it difficult to "flick" the bike from one side to the other in a chicane.
- Will give a light feeling in the front.
Front
Too hard spring ratio:
- Good under braking.
- Creates understeer.
- It feels harsh in the corners.
Too soft spring ratio:
- Gives easy turning into corners.
- Creates oversteer.
- Can cause front to tuck under.
- Bad under braking (diving).
TROUBLESHOOTING SHOCK DAMPING PROBLEMS
Shock Adjustment Locations:
Rebound adjustment (if applicable) is located at the bottom of the shock.
Compression adjustment (if applicable) is located at the top of the shock or on the reservoir.
Spring preload is located at the top of the shock.
Shock - Lack of Rebound:
Symptoms
The ride will feel soft or vague and as speed increases, the rear end will want to wallow and/or weave over bumpy surfaces and traction suffers.
Loss of traction will cause rear end to pogo or chatter due to shock returning too fast on exiting a corner.
Solution
Insufficient rebound - Increase rebound until wallowing and weaving disappears and control and traction are optimized.
Shock - Too Much Rebound:
Symptoms
Ride is harsh, suspension control is limited and traction is lost.
Rear end will pack down, forcing the bike wide in corners, due to rear squat. It will slow steering because front end is riding high.
When rear end packs in, tires generally will overheat and will skip over bumps.
When chopping throttle, rear end will tend to skip or hop on entries.
Solution
Too much rebound - Decrease rebound "gradually" until harsh ride is gone and traction is regained. Decrease rebound to keep rear end from packing.
Shock - Lack of Compression:
Symptoms
The bike will not turn in entering a turn.
With bottoming, control and traction are lost.
With excessive rear end squat, when accelerating out of corners, the bike will tend to steer wide.
Solution
Insufficient compression - Increase compression "gradually until traction and control is optimized and/or excessive rear end squat is gone.
Shock - Too Much Compression:
Symptoms
Ride is harsh, but not as bad as too much rebound. As speed increases, so does harshness.
There is very little rear end squat. This will cause loss of traction/sliding. Tire will overheat.
Rear end will want to kick when going over medium to large bumps.
Solution
Too much compression - Decrease compression until harshness is gone. Decrease compression until sliding stops and traction is regained.
Rear Shock Problems Possible Cure
Race sag too great - Increase preload.
Race sag too small - Reduce preload.
Rear squats on acceleration - Stiffer spring, increase anti-squat angle, slightly increase compression damping.
Very Harsh ride over ripples - Reduce compression damping.
Bike wallows - Increase rebound damping.
Rear jacks up too fast on braking - Increase rebound damping.
Rear end chatters exiting slow corners - Increase rebound damping.
Bike kicks off ripples or bounces on bumps - Increase rebound damping.
Rear end pumps down on bumpy corners - Reduce rebound damping.