The best suspension setting depends on many variables, including the riding terrain and the rider's weight, riding style and individual preferences. The front (1) and rear (2) suspensions on your Timbersled ARO snowbike system are easy to adjust.
Just follow these simple steps:
1. Ride your snowbike. Ride on the type of terrain you most often intend to ride to fully experience the existing suspension settings before making any adjustments. Optimal suspension settings can change depending on the terrain.
2. Adjust the spring preload (3) to tune the vehicle balance for ski pressure and weight transfer. After riding, you should be able to determine if the snowbike needs more or less weight transfer and ski-to-ground pressure. In general, the more spring preload that is added, the less weight that will be transferred. Heavier riders will typically require more spring preload than ligher riders.
Always perform shock spring preload adjustments with the weight of the vehicle removed from the shock and with the shock at full extension. Make spring preload adjustments in small (approximately 1/16th of an inch) increments and test ride quality between adjustments.
- If your ride requires less weight transfer to the rear suspension, increase the rear track shock's spring preload.
- If your ride requires more weight transfer to the rear suspension, decrease the rear track shock's spring preload.
- If it feels like the ski-to-ground pressure is too heavy, making it difficult to steer, increase the preload on the front track spring and decrease the preload on the back track spring.
- If it feels like the ski-to-ground pressure is too light (the ski lifts from the ground too readily), decrease the preload on the front track spring and increase the preload on the back track spring.
For ARO bikes with monotube shocks (shocks with NO clickers), the rear track spring preload also can be decreased to decrease ride stiffness. It can be increased to increase ride stiffness and reduce bottoming out. However, for ARO bikes equipped with clickers, using the clickers is typically the best way to adjust for these ride quality characteristics.
3. Adjust the shock clickers (4), if equipped, to tune the ride quality for a stiffer or softer ride. For ARO models with shock clickers, you can adjust the clickers to control bottoming and adjust for ride comfort. Note: To learn more about compression and rebound damping with shock clickers, see the sections on QS3 Shocks and 1.5 Zero LSC-R Shocks.
- For a softer ride, turn the clicker(s) counter-clockwise to decrease compression or rebound damping.
- For a stiffer ride or to stop bottoming out the front or rear suspension, turn the front or rear track shock clicker clockwise to increase compression or rebound damping.
4. Repeat as needed. Test ride the snowbike and continue making small spring and clicker adjustments until you achieve the perfect ride.
For improved handling and additional control of the front ski, the Timbersled TRIO front shock can be added to the front forks and spindle.
Timbersled IFP Shocks
All standard ARO models have Timbersled Internal Floating Piston (IFP) Shocks for both the front track and rear track. Timbersled IFP shocks are only adjustable through the spring preload (1). They do not have clickers for adjusting compression and rebound damping. Although the factory spring preload settings are usually sufficient for most riders, if you find adjustment is needed, NEVER adjust the spring preload beyond the minimum and maximum spring preload settings. Note: A spanner wrench (part number 2871095-329) is needed to adjust the Timbersled IFP shock spring preload.
FOX® QS3 Shocks
All Timbersled ARO LE models, including the Timbersled 3-Inch model, have QS3 shocks for both the front track and rear track. FOX® QS3 Shocks are spring preload adjustable (1) and have clickers (2) for adjusting compression damping. Remember to adjust your snowbike's spring preload first before moving on to adjust the clickers. if spring preload adjustment is needed, never adjust the QS3 shocks beyond their min/max preload values. Compression damping slows down (dampens) the shock compression that happens when the snowbike hits a dip, bump or other disturbance. The higher the compression damping, the slower the shocks will compress when encountering a disturbance.
QS3 clickers have the following three positions:
- Soft: Turn the clicker all the way to its farthest counter-clockwise position to achieve a softer or more plush ride with the least amount of compression damping.
- Medium: Turn the clicker one click from its soft position to achieve an intermediate ride (between plush and stiff) with a medium amount of compression damping.
- Stiff: Turn the clicker two clicks clockwise from its soft position for a stiffer ride with the highest amount of compression damping.
FOX® 1.5 Zero LSC-R Shocks
Timbersled ARO 120 SX models have FOX® 1.5 Zero LSC-R shocks for both the front and rear track. In addition to being spring preload adjustable (1), FOX® 1.5 Zero LSC-R shocks have two clickers that adjust compression damping (2) and rebound damping (3). Remember to adjust your snowbike's spring preload first before moving on to adjust the clickers. If spring preload adjustment is needed, never adjust 1.5 Zero LSC-R shocks beyond their min/max preload values.
Compression damping and rebound damping work hand in hand to provide a softer or stiffer ride. Increasing compression damping creates a stiffer ride by slowing down (dampening) the shock compression that happens when your bike hits a dip, bump or other disturbance. Increasing rebound damping also creates a stiffer ride by causing the shocks to rebound (extend back to their normal position) more slowly after compressing when the bike hits a disturbance. Too much rebound damping on bumpy terrain may not allow the shocks to recover quickly enough after a bump to allow the shock to be ready for the next bump.
The 1.5 Zero LSC-R shock clickers have a total of 24 compression damping clicker positions and a total of 25 rebound damping clicker positions, which allows for more minute changes and finer tuning of ride quality. The shock clickers can be turned all the way counter-clockwise for a softer or plusher ride with the least amount of compression or rebound damping and can be turned all the way clockwise for the stiffest ride with the most amount of compression or rebound damping. Keep in mind that adjustments to the spring preload will require you to reset the compression and rebounding damping to find the best settings once again.
After setting the spring preload, it is suggested that you start with both compression and rebound damping set at their softest settings (clickers turned all the way counter-clockwise) and slowly try out more compression and rebound damping until you achieve your perfect ride.
Front Track Shock Spring Settings
Factory settings, combined with user adjustments to the front track shock spring, should be sufficient in providing the best riding experience for most riders. Always perform shock spring preload adjustments with the weight of the vehicle removed from the shock and with the shock at full extension. Never adjust spring preload to an installed length longer than the factory length or shorter than the minimum length as shown in the following chart. Damage to the suspension could result. When decreasing preload, make sure at least two turns of preload are holding the retainer against the spring.
|MODEL||FRONT SHOCK||SPRING RATE||FACTORY INSTALLED LENGTH||MINIMUM ALLOWABLE INSTALLED LENGTH|
|ARO 129||Timbersled IFP||150||7-13/16"||8-7/16"|
|ARO 129 LE
ARO 129 LE 3"
ARO 137 LE
|ARO SX 120||FOX® 1.5 ZERO LSC-R||200||7-13/16"||7-9/16"|
Rear Track Shock Spring Settings
Always perform shock spring preload adjustments with the weight of the vehicle removed from the shock and with the shock at full extension. If adjustments to the factory installed springs are not sufficient for riders over 300 pounds (136 kg), optional stiffer springs are available through your Timbersled Dealer. To find a dealer near you, use the Dealer Locator.
|MODEL||REAR TRACK SHOCK||SPRING RATE||FACTORY INSTALLED LENGTH||MINIMUM ALLOWABLE INSTALLED LENGTH|
|ARO 129||Timbersled IFP||175||7-13/16"||
|ARO 129 LE
ARO 129 LE 3"
ARO 137 LE
|ARO 120||FOX® 1.5 ZERO LSC-R||200||7-13/16"||7-9/16"|
TSS Shock Tuning
The TSS suspension system is intended to work in harmony with the in-track rear suspension to create a dual rear suspension feel that is unique to a Timbersled snowbike. It is not intended to have a soft squishy feel like the stock motorcycle rear suspension, and it's important that you do not try to tune it to feel this way. For maximum suspension performance follow the tuning instructions.
The TSS shock is preset from the factory with 260 psi. Use a FOX® Float air pump to adjust the spring rate and preload of the TSS shock. Your shock will have a sticker on it with the minimum, maximum and factory pressure settings. The suggested TSS pressures can be found in the following table.
To tune the TSS shock:
1. Take the weight off the shock by lifting the bike from under the engine or tipping it on its side.
2. Remove the shock's silver valve cap.
3. Thread the pump onto the shock's valve stem until the pump pressures up and you are able to see the supplied pressure on the gauge. When the pump pressures up, the shock instantly loses 20 psi from the volume it takes to fill the pump hose. You will need to compensate for this when checking pressures.
4. When finished, unthread the pump. You will hear a release of air when unthreading the pump, but this will not affect the exact pressure you gave the shock. When tuning your TSS shock, it is best to add or subract air pressure in increments of 25 psi at a time. Be very careful to not get snow or water inside the valve system, as this can cause the shock to leak air.
5. For a more refined tuning method, you may use the TSS shock O-ring, which can be found on the outer shock body. The O-ring is designed to be a gauge for measuring the amount of shock travel you are using when riding.
To measure the amount of shock travel:
1. Slide the O-ring down to its lowest point.
2. Ride the snowbike for approximately 10 minutes.
3. Stop the bike and measure the amount the O-ring has moved. To do this, measure the distance between the O-ring's starting point (when moved down to its lowest point) and the O-ring's current location after a 10-minute ride.
The O-ring movement equals the amount of TSS shock travel. The TSS shock has a max travel distance of 1.5 inches to bottom out. It is recommended that the targeted amount of shock travel be about 1-1/8 inches of stroke.
4. Tune the TSS shock in increments of 25 psi to reach the targeted amount of shock travel (1-1/8 inches) and accomplish perfect calibration. Each time you make a pressure adjustment (of 25 psi), slide the O-ring back down to its lowest point and ride for approximately 10 minutes before rechecking your shock travel distance.
Timbersled TRIO Kit
The Timbersled TRIO is an accessory front shock. To change the air pressure, first use the supplied shock pump to set the air pressure in the EVOL chamber. To do, locate the lower Schrader valve and attach the supplied pump. See the chart below for the recommended setting. To ensure proper ride characteristics, always set the pressure in the EVOL chamber first. Make sure the ski is off the ground so the shock is not under load and is fully extended before setting air pressures.
Next, set the air pressure in the main shock chamber. To do so, locate the TRIO’s uppermost Schrader valve and attach the supplied pump. Pump to the recommended setting shown on the chart below.
Ensure all tools are accounted for and all steps have been completed. DO NOT exceed maximum pressures. Contents of shock are under pressure. Never incinerate or puncture and never disassemble without consulting your service manual. Any of those may result in serious injury or death.
EVOL air chamber tuning tips:
- The infinitely adjustable pressure setting in the extra volume (EVOL) air chamber regulates spring rate in the final portion of the stroke and controls the bottom-out characteristics of the shock. Increasing air pressure in the EVOL air chamber will give a more progressive spring curve to protect against harsh bottom-outs. Decreasing air pressure will provide a more linear curve to maximize usable travel.
- When combined with the infinite adjustability of the main air spring, the EVOL air chamber allows the shock’s spring curve to be tuned for any conceivable ride weight and/or terrain condition. The pressure in the EVOL air chamber is adjusted to control the bottom-out characteristics of the shock.
FOX® Float tuning tips:
- Your TRIO main shock chamber is a FOX® Float shock specifically designed for Timbersled to increase spring rate, maintain ride height and improve the overall ride and handling characteristics of the snow bike.
- For Timbersled TRIO shock applications, the recommended main chamber air pressure settings shown above are unique to the Timbersled TRIO application and should be followed to achieve the best overall ride characteristics.
- The spring rate is controlled by air pressure in the main body. Air pressure is infinitely adjustable, making Float the most progressive and adjustable air shock on the market.
For more information about TRIO, see the installation instructions for the TRIO kit.
More maintenance information can be found in your Owner's Manual.
To view diagrams and find replacement part numbers, view the online parts catalog.
FOX® is a registered trademark of Fox Factory Inc.