Suspension Setup Guidelines

I'm not an expert on this stuff, but I've compiled some tips over the years. There are three (3) possible adjustments on the front and rear suspension of a motorcycle: spring preload, compression damping, rebound damping. The spring preload sets the ride height of the bike and determines how much of the total travel will be available for compression and how much will be available for extension. Damping keeps the bike from behaving like an old Cadillac - i.e., still bouncing 10 seconds after hitting a bump. Compression damping slows the shock when it is being compressed. Rebound damping slows the shock when it is rebounding.

Set the preload on each end so that the bike settles 1/3 of its total travel -- look in your owner's manual for total suspension travel. This ("sag") is measured between (a) the wheel suspended off the ground, and (b) you on the bike with all applicable gear, luggage, passenger, etc. Use less sag for smooth roads and fast riding, say 25%. On shock absorbers: get the sag/preload right before messing with the damping. Start at the shock manufacturer's recommendations. Only change one setting at a time, and don't change damping more than 2 clicks at a time. For compression damping, increase until expansion joints or sharp bumps are jarring, then back off one click. Don't forget that when you increase preload, you have to increase rebound damping and vice versa for decreasing preload.

Front Suspension Symptoms, Likely Causes & Possible Solutions

Symptoms:Not using full travel, feels harsh, poor traction in bumpy corners
Causes: Overly stiff springing or compression damping
Solutions: Lower air pressure; reduce compression damping; softer coil springs
Symptoms: Bottoms, soft throughout travel
Causes: Spring rate too low throughout travel, or too little compression damping
Solutions: More air pressure; increase compression damping; stiffer coilsprings Symptoms: Bottoms, but compliant over small bumps Causes: Spring rate not progressive enough Solutions: Raise oil level Symptoms: Harsh over large bumps, but good over small ones Causes: Spring rate too progressive Solutions: Lower oil level Symptoms: Excessive sack, feels soft initially but doesn't bottom Causes: Initial spring rate or preload too low; springing too progressive Solutions: Add air pressure *and* lower oil level; increase spring preload Symptoms: Harsh over small bumps but uses full travel Causes: Initial spring rate or preload too high, springing not progressive enough, or too much compression damping Solutions: Raise oil level *and* lower air pressure or install softer springs; reduce compression damping; reduce spring preload Symptoms: Takes first bump in a series well but harsh over later bumps, poor traction in washboard corners Causes: Too much rebound damping Solutions: Use thinner fork oil (or decrease rebound damping if adjustable) Symptoms: Front end springs back too quickly after bumps, poor traction in bumpy corners Causes: Not enough rebound damping Solutions: Use thicker fork oil (or increase rebound damping if adjustable)

Rear Suspension Symptoms & Causes

Symptom: Not using full travel, feels harsh, poor traction accelerating out of bumpy corners Cause: Overly stiff springing or compression damping, possibly too much preload Symptom:Bottoms, feels soft throughout travel Cause:Spring rate or compression damping too low Symptom: Bottoms, feels harsh, sinks far into travel with rider board Cause: Too little preload, perhaps combined with too soft spring Symptom: Wheel chatters over small bumps during braking or downhills, doesn't hook up accelerating out of washboard turns Cause: Too much preload (perhaps because of soft springs) causing suspension to top out; possibly too much compression damping Symptom: Kicks over large square edge bumps, but not over large rolling bumps Cause: Too much compression damping Symptom: Kicks over rolling bumps and square edge bumps Cause: Too little rebound damping. Symptom: Rear end takes first bump in a series but is harsh on later bumps. Poor traction out of bumpy turns or braking on washboard Cause: Too much rebound damping. Symptom: Back end extremely springy and shock doesn't respond to adjustments Cause: Damping is gone because of low nitrogen pressure, tired oil, or damaged internal components.