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If you talk to people about suspension and what they want out of it and you’ll get a multitude of answers. Most will be happy simply to make their bikes comfortable and predictable. Modern suspensions with adjustable preload and damping will provide this. As a rider’s skill improves, and he pushes his bike and tires harder, all suspension variables become more sensitive and crucial to get right. At this point the rider is beyond ride quality. What’s needed is balanced grip in the front and rear. At this level of riding questions of bike attitude and damping come to the forefront where as previously (quality first) they had very little influence to the rider. If there is one thing I’ve learned it’s the rider (skill) who makes the difference not the bike. As the skills increase suspension plays an ever important role in the riders expectations.

With that said, lets get into the nuts and bolts of suspension set up. Without spending the next three pages going over all the things that can upset and cause poor suspension performance, I will go over the most common. These are things that must be checked/corrected before attempting to properly setting up a motorcycles suspension. While these all seem very basic, be reassured they can have a tremendous negative impact on your suspension and your ability to figure out what’s wrong.

* Chain Tension – It goes without saying that a properly adjusted chain is critical. As a chain wears you will get tight spots on the chain. Be sure and adjust the chain at the tightest point along is length. A few years ago I was invited to listen to a suspension seminar put together by a SoCal dealership. Participating was a suspension specialist who worked with the Honda AMA team. One interesting topic he discussed at length was the chain, pivot point and the forces that play with suspension during acceleration. He explained that when a bike accelerates the chain force tries to extend the rear suspension. Auto’s are just the opposite. Hit the gas and the rear immediately squats mostly due to weight transfer to the rear. On the bike that is not the case. The tension in the chain, acting at a slight angle to the swing arm pivot, exerts a downward force that will extend the suspension. This is most noticeable in the lower gears where torque has a greater influence. Watch a bike on a dyno or coming out of a slow corner and hitting second gear. He went on to explain this is why race bikes have adjustable pivot points: more angle more lift, less angle and less lift. As he explained, when a bike is in a corner the suspension is loaded which reduces swing arm angle. As you accelerate weight transfers to the rear. Chain forces begin when throttle is applied which would negate the weight transfer to the rear but because of the increased travel of the compressed suspension (less angle) the chain forces are too weak to overcome the bike wanting to squat. With the rear now squatting the front will lift more than normal which results in the front end pushing to the outside of the corner. The other extreme can occur as well. If the angle is such that chain forces exert enough force to lift the suspension so much so that the rear tire may kick out. Once it steps out the suspension unloads further. You see where this will lead you. While this is very technical I thought it was very interesting. Something to keep in mind if you are making gearing changes and find your bike wanting to run wide or the rear tire is breaking loose coming out of the corners or in most cases the pre-load was never set properly. Setting pre-load is coming up shortly.
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