"Motorcycles 101: How to Set Motorcycle Suspension Sag
My name is Kenyon Kluge. I'm from Santa Cruz, California. I'm a team owner and rider for K Squared Racing. I'm also the team manager and rider for Zero Motorcycle Racing. If you want to find out more information about me you can look at my website, ksquaredracing.com or for more information on Zero Motorcycles go to zeromotorcycles.com. And now I'm going to talk to you about motorcycles. So the way you set your sag on your motorcycle is, First the best thing to do is get two buddies to help you out. It will make things easier, you can do it with just two people but three is optimal. Then pick an end either the front or the back to start with. Today I'm going to start with the front. The next key step is to pick a point your going to measure from and two. So on the front I like measuring from the bottom of the fork, to the top of the dust seal. That's going to be my measure point right there. Then what your going to do is lift the bike, and completely top it out. Which we call the topped out sag. And measure that distance between those two points, with the suspension completely topped out. Once you have done that you want to have a friend hold the bike in an upright position. Then you the rider get on, with your gear on preferably. And get into your riding position, so get into the position your most likely riding in. While your in that position have your friend that measured the first measurement measure the second measurement. This is going to be your sag measurement, once you subtract the first measurement from the second measurement.
Forks can often have stiction in them as well, so it helps to give it a little bounce then take that measurement one more time. And see what the difference is between the two. And the difference is going to be the stiction in your forks.
Once you've done the front your going to repeat the exact same thing on the rear. The rear might be a little bit more tricky to find a measurement point. I like to go from the axle to a fixed point on the tail section. And the key there is to make sure that fixed point isn't going to move around. So when you top it out or lift it, always lift from the frame and not to the point that you're measuring to. And that will give you a nice consistent measurement. And then again the same thing. You're going to get on the bike and assume the riding position that your normally in. Have someone steadying the bike for you. And measure the top dot distance, and measure the riding sag. Subtract the two from each other and that's your sag measurement.
Once you've done that you can adjust you sag by setting the two bolts at the top here. Dialing counter clockwise, is going to give you more sag. So it is going to lighten the spring load. And then on the rear the same thing, there is a counter down here, you can dial it out, to lessen the pressure on the spring, to give yourself more sag. Or dial it in to get less sag.
You want your sag to be about 45 to 50 millimeters on the front, and about 35 to 40 millimeters of sag on the rear for street applications. For race applications that will get tighter. To about 35 to 40 millimeters on the front and 25 to 30 millimeters in the rear of the bike."