A properly tuned suspension can provide a racer with a distinct advantage over his competition, Unfortunately stock suspension can only perform adequately for a small number of riders based on the setting developed by the factory.
A properly tuned suspension can provide a racer with a distinct advantage over his competition, Unfortunately, a stock suspension can only perform adequately for a small number of riders based on the setting developed by the factory. A rider may need to change many different components of their suspension to achieve his or her goals. We know most motorcycles are competitive off the showroom floor and can win races, but one of the most overlooked modifications is suspension tuning. In order to win races and remain competitive, a racer needs to keep his bike tracking straight and keep the power to the ground, along with providing the plushness to remain fresh and strong during the last laps of a race. (make your pass while the other riders are tired and just trying to hold their line!) GPS SUSPENSION CAN SUPPLY YOU WITH THE WINNING PACKAGE YOU NEED TO REACH YOUR GOALS, EVEN IF YOU ARE A WEEKEND RIDER LOOKING FOR A PLUSHER RIDE) Please refer to this tuning guide as often as needed and if you need any assistance with tuning give us a call us @ 1-978-230-2011.
RACE SAG: Set the race sag in the range listed on your spec sheet. This is the most important of the suspension settings. After you have spent some time riding and have dialed in your settings, you can try some different sag measurements to find what you like best for your riding style. As a guideline or general rule, you should have about 100 - 103 mm of race sag on 125/250/450, on the 85's start at 80 to 85mm. To set your race sag measure from the rear axle to a perpendicular point on the rear fender while the bike is on a stand record the measurement, this is your reference or zero points. Remove the bike and have the rider sit in the position he normally rides in if available have another person hold the bike by the forks so the rider can keep his feet on the pegs. Take a second measurement and record it, then subtract the fist measurement from your second and that will be your race sag. If you are not within the recommended spec adjust the spring preload. (Your personal pre-load adjustment may be more or less depending on your personal feel and preference).
FREE SAG/STATIC SAG: MAKING SURE YOUR SPRING IS CORRECT This measurement is taken to determine if you have the proper spring rate for your weight. Observe how much the motorcycle sags or drops under its own weight. If the bike tops out or has less than 25 mm of sag then the spring is too soft! If the bike's free sag is over 40 mm the spring rate is too stiff. To obtain your free sag take your first measurement while the bike is on the stand then remove the bike from the stand (make sure to hold only the tubes and not apply additional pressure to the top of the motorcycle) without the rider measure to your reference point and subtract that measurement from the first, if you are not with within 25mm to 40mm adjust the spring preload if your static sag is within the range and your race sag is 100-103 you should be fine. If you have any questions contact us immediately.
Your suspension will be pre-set and rideable when revealed by GPS, but you may find it necessary to adjust the settings for your riding style or track preference. These differences require you to set-up the adjustments. This guide will help you get the motorcycle dialed in, and will help if you are using stock suspension. If you are having troubles dialing in your suspension, contact us immediately.
Setting the rebound: SHOCK 1.) Find a relatively fast straight away with braking bumps, acceleration bumps that lead into the entrance of a corner. Reduce (Turn clicker out) the rebound damping until the rear end begins to hop or feel loose. Finally, increase (Turn clicker in) the rebound damping until the sensation goes away. 2.) Find a large jump that tends to bounce the motorcycle after hitting it. If the rear end bounces up, add rebound. (Turn clicker in) 3.) Find some large whoops. The motorcycle should track straight through the whoops with the rear wheel extending to the ground before the next impact. If it does not perform as described, it is packing and the rebound dampening should be reduced! (Turn clicker out) if the motorcycle kicks side to side the add rebound. (Please note this guide does not apply to sand set-up) 4.) Find a corner with acceleration bumps during the exit. The rear of the motorcycle should follow the ground. If the rear end packs up, reduce the rebound. (Turn clicker out) (If this fails to soften the compression by turning out two clicks or open high-speed adjuster another 1/4 to 1/2 turn until it smoothes out.) Setting the compression: SHOCK 1.) Find some rough sections, a large jump and a couple of "G-Outs". The shock should bottom on the roughest section but it should not be a slamming sensation. Add compression to fight bottoming. (Turn clicker in.) But avoid going too far as the suspension's ability to react to small variations of the track will be compromised in the trade. Remember the adjusters have a primary effect on the low speed, so even a large change in setting may only effect bottoming resistance slightly. Remember bottoming your suspension is not necessarily a bad thing. You should strive to bottom off the biggest bottoming load obstacle on the trail. If you don't you're not getting maximum travel & plushness from your suspension. Run your suspension as soft as you can get away with but remember that if the track has sand sections or lots of g-loads this will work against you. For sand refer to our sand tuning section. Setting the compression: FORKS 1.) The folks should react to all track conditions. If the forks seem harsh on small braking bumps, holes, soften the compression. (Turn clicker out) If they are relatively smooth, stiffen (Turn clicker in.) until they do feel harsh and then turn back a click or two. Another possibility is the spring is too stiff for rider weight. 2.) Now find the rough part of the track. The forks should bottom over the worst g-load or jump. If harsh bottoming occurs, add oil in 5-mm increments.
Setting the rebound: FORKS 1) Find a short sweeper. When the forks compress for the turn, the speed at which the forks return is the energy that pushes your front wheel into the ground. If the forks rebound too quickly, the energy will be used up and the bike will drift wide, or wash. If the rebound is too slow, the bike will tuck under and turn too soon to the inside. 2). With the bike turning well, the wheel should return to the ground quickly and not deflect off successive impacts. If it does, reduce the rebound. (Turnout)
HARDPACK: GUIDELINES Normally set the shock high-speed compression (if the bike is equipped with an HS adjuster) and low-speed adjuster to a softer position. Turn the clickers front and rear out & turn the high speed out 5-10MM at a time. These adjustments will maximum wheel contact and provide plushness.
SANDY CONDITIONS: Sand conditions require more low-speed compression and rebound. Start by adding 1-2 clicks (Turn clicker in.) of rebound and as the track gets rough, add compression 1-4 clicks. (Turn clicker in.) Harshness is a result of packing in forks. Remember to add compression (Turn clicker in) to help keep the front end from packing and run your fork rebound the same or 1-2 clicks faster to keep the bike up on top of the sand. The rear suspension may exhibit some swapping. To eliminate swapping begin adding compression (Turn clicker in) until the bike tracks straight and then add rebound (Turn clicker in) to keep the rear following the terrain. Don't be concerned if your clickers are turned in while riding in sandy conditions the most important thing is to make sure the bike tracks and remains stable in the sand!
ACCELERATION & DE-ACCELERATION HEAD SHAKE; First, we need to determine if the head shake is occurring during acceleration or de-acceleration (chopping the throttle) If you find the front end skipping or wandering (seems to be searching for traction) and or starting to swap while under acceleration, you will normally need to add rebound (turn in) or reduce your compression 2 clicks. lastly, make sure you have the proper spring rate for your weight. (normally associated with too stiff of a spring) If you experience heads shake when you let off the throttle then you may need to reduce the rebound (turn out) or add 2 clicks of compression to help hold the front end up. Check your spring rate to ensure it is the right rate for your weight. (normally to light or soft of a spring) You can also adjust the fork tubes in the clamp to a flusher position to provide more stability.
You may have to add a bit of oil this will help with the front end diving, you can also try to tighten your steering stem to reduce head shake, running your fork flush will also reduce head shake, but will also reduce the turning ability of the bike. Keep notes on where you experience head shake.
EXCESSIVE REAR END KICKING OR HOPPING; Check for packing, which is identified by in hard to load conditions. If you think your bike is packing have an experienced person watch to see if the bike is not returning to the ground decrease RB until bike tracks and wheel returns to the ground without excessive kicking out or swapping. A harshness sometimes associated with suspension is having the suspension too soft and it feels like to bike is bottoming out increase compression until the harshness or bottoming out feel is lessened. This cannot be avoided if you brake improperly and lock the rear wheel up and/or pull in the clutch, on the entrance to corners. Excessive kicking side to side is (deflection) associated with rebound being too fast add rebound turn in clockwise to reduce this effect Keep a record of the tracks and conditions you ride at and record the different settings. Now you can have accurate records that will help you set your bike up before you arrive at the track!
KEEP YOUR SUSPENSION FRESH: MAINTENANCE TIPS; The dampening of your suspension changes as the components is used. This is caused by wear and oil viscosity breakdown. It is important that your suspension has regular maintenance. Improper assembly or inadequate fluids will drastically alter the way these components were designed to perform. For the shock, The linkage should be cleaned and greased once a month. The shock's oil should be changed every 20-30 hours of use unless severe conditions exist such as continuous sand riding. Seals will normally last a season, so once a year we recommend replacing them. For the folks, we recommend that you bleed off the air pressure during your daily ride or race or when finished riding. Oil should be changed at about 30 hours of use. A complete service is suggested every 3 months. Seals and bushings can last a season but it recommended you change them at least twice per year, worn bushing can cause streaking on the fork tubes and can damage the DLC coatings very quickly. Do not power wash upwards around your seals and wipers this only pushes the dirt and sand deeper into the seal area speeding up wear.
* * Note do not attempt to tune a motorcycle suspension by yourself, many of the traits can be misdiagnosed leading to improper tuning and may severely affect your riding and performance.