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 Post of a member: Here is OpenClassKiller's description that I linked. I think everyone agreed that this is the best description of suspension that they had read. Again, I repeat, I connot take credit for the following work by OpenClassKiller.... openclasskiller CBR 600 Pilot Posts: 44 (7/20/01 7:28:28 am) suspension for dummies Actually, the subject line would be a good title for one of those books! There's a lot of misunderstanding about suspension. I'll try to explain some things, since the question was asked kind of gererally. The suspension is a spring. That's pretty much it. Really. So, why the he!! are there so many adjustments if it's a simple spring? Well, the spring will store energy (say after going over a bump), and if it's left alone, that spring will return that energy back to the bike. Pretty soon, you'll have a bike that's oscillating up and down like a couple of teenagers having sex for the first time. That's a lot of up and down! So, to prevent the oscillations, engineers put in things call dampers. The dampers are a way of dissipating the stored energy of the spring. The dampers work by forcing oil through a small hole. The oil resists flowing through the hole, and bingo, you've got something to kill the oscillations (bummer for the two teenagers). There are two sets of dampers on a CBR suspension system. There is a COMPRESSION damper and a REBOUND damper. Note that dampers only work in ONE direction. That's why there are two of them - to control the spring in up AND down motion. The compression damper slows the compression of the spring. So, for the front fork the compression damper will slow the rate at which the front for compresses, like when under braking. The rebound damper works in the other direction. When the spring unloads (springs back to normal length) then the rebound damper kicks in to slow down that motion. For the front forks, the compression damper is a little screw located on the lower fork leg, just below the caliper brake mount. The rebound damper adjustment is on the upper end of the fork cap, in the center. Adjustment directions are in the maual, but here's how to do it: using a screw driver, turn the adjustment screw clockwise, counting the number of turns, untill the screw seats lightly. DON'T FORCE IT! Remember the number of turns as this was the setting. Note that when the screw is fully seated, you have MAXIMUM damping. Now turn the screw counter clockwise to the desired setting. The stock setting for the CBR600 is 1 1/4 turns out from max for the compression damper. The rear shock compression damper is located on the remote reservoir, which is attached to the left side of the rear sub-frame. The rear shock rebound damper is at the base of the shock body, looking from the right side. Again, see the manual for more info. Now for the preload! Preload is exactly what it means - you're 'preloading' the spring. Here's how it works: there is a spacer on placed on inside the fork tube, on the top of the spring which has a threaded adjustment on it. That the thing you see at the top of the fork cap. By turning the preload clockwise - your pre-compressing the spring. If you turn it counter clockwise, you un-compressing the spring. What happens is that the moment you sit on the bike, you add a load which the spring has to balance. If you PRELOAD the spring a lot, then the spring will not move very much when you sit on it. It doesn't need to travel very much to balance the load (your weight). If you lightly preload the spring, it will compress a LOT to balance the load. The amount of travel the suspension goes through when you sit on it is called SAG. The preload should be adjusted to an INDIVIDUAL RIDER'S WEIGHT. The optimum sag is ~25-35mm. Preload should be adjusted to get the optimum sag. That way the suspension is right in it's sweet spot, and the bike geometry is at its optimum. Guy's talk about the number of lines showing on the front fork cap as a measure of how much preload they have dialed in. Note that MORE IS NOT BETTER! It's a personalized adjustment. IMPORTANT: Preload does not have any effect on the 'stiffness' of the spring. You can't make the spring stiffer with preload. The spring stiffness is solely a function of the spring rate (or spring constant). As for the rebound setting, most guys like to set the rebound so that the bike will rise then settle slightly. Just push the front end down, and watch the motion as it comes back. It should rise at a nice rate, then settle back. The same goes for the rear, but the rise rate is usually a bit slower. As for the right compression damping setting. Well there is no way to check that on a stationary bike. You just can't physically compress the suspension fast enough to get it to work. You'll have to go by feel. Start with the factory setting and ride it a while, then make a SMALL change. Remember to turn the set screw all the way in and count the number of turns as you go out (counter clockwise). That way you always measure from the same reference point. Well, that got a lot longer than I thought it would. If you're confused, don't worry. It's not going to throw you off the bike. Just make small adjustments, try to record what you did, and have fun. And don't be afraid to ask someone for help. Racers are a good source. These guys are constantly working on suspension settings.