V Cannondale P/N 951-6001126 Safety signals Important information concerning safety is distinguished in this manual by the following notations: Introduction All of Öhlins advanced suspension products are adepted to the brand and model. This means that length, travel springaction and damping characteristics, are tested individually just for the vehicle that you have decided to fit with Öhlins suspension. WARNING! 1. Installing a shock absorber, that is not approved by the vehicle manufacturer, may affect the stability of your vehicle. Öhlins Racing AB cannot be held responsible for any personal injury or damage whatsoever that may occur after fitting the shock absorber. Contact an Öhlins dealer or other qualified person for advice. 2. Please study and make certain that you fully understand all the mounting instructions and the owners manuals before handling this shock absorber kit. If you have any questions regarding proper installation procedures, contact an Öhlins dealer or other qualified person. 3. The vehicle service manual must be referred to when installing the Öhlins shock absorber The Safety alert symbol means: Caution! Your safety is involved. WARNING! Failure to follow warning instructions could result in severe or fatal injury to anyone working with, inspecting or using the suspension, or to bystanders. Before installation Öhlins Racing AB can not be held responsible for any damage whatsoever to shock absorber or vehicle, or injury to persons, if the instructions for fitting and maintenance are not followed exactly. Similarly, the warranty will become null and void if the instructions are not adhered to. CAUTION! Caution indicates that special precautions must be taken to avoid damage to the suspension. Contents Saftey signals ................................................ 2 Tuning the suspension ................................... 3 Design ........................................................... 3 Function ........................................................ 4 Compression damping ................................ 4 Rebound damping ....................................... 4 Settings ......................................................... 5 Preload adjustment ....................................... 6 Setting the damping ...................................... 7 Setting your vehicle: ...................................... 7 Start with rebound damping ........................ 8 Compression damping ................................ 8 Inspection and maintenance ......................... 9 NOTE! This indicates information that is of importance with regard to procedures. NOTE! Öhlins products are subject to continual improvement and development. Consequently, although these instructions include the most up-to-date information available at the time of printing, there may be minor differences between your suspension and this manual. Please consult your Öhlins dealer if you have any questions with regard to the contents of the manual. © Öhlins Racing AB. All rights reserved. Any reprinting or unauthorized use without the written permission of Öhlins Racing AB is prohibited. Printed in Sweden. 2 Shock absorber position Gas Oil Oil Gas Separating piston Oil Gas and oil Oil Shock absorber piston 1 2 3 4 1. External reservoir with hose connection 2. External piggyback reservoir 3. Internal gas reservoir 4. Emulsion shock absorber Tuning the suspension Road holding qualities All vehicles are designed with a suspension geometry that includes wheel movements and angles. The changing of components can affect this and it is therefore essential that both the rear and the front ends match each other. Changing to Öhlins suspension gives optimum performance only when both the front and the rear suspension interact properly. It is of greatest importance that the front and rear loaded height (ride height sag) are within the specified values in the Mounting instructions. Design Most of Öhlins suspensions are of the De Carbon type. The fluid is put under gas pressure and the gas and the fluid are kept apart by a separating piston. The separating piston is often fitted in a separate fluid reservoir, connected by hose (Fig.1) or fixed direct on top of the shock absorber (Fig.2) (piggyback). There are also models where the separating piston is fitted inside the main shock absorber (Fig.3) (internal gas reservoir). Öhlins even manufacture a small number of emulsion shock absorbers that do not have a separating piston (Fig.4). Pressurization of the fluid is made with nitrogen. The pressurization prevents cavitation of the fluid and the shock absorbing action is therefore more even. The external fluid reservoirs also contribute to better cooling of the fluid, giving longer service life to both the fluid and components. Öhlins shock absorbers have integrated temperature compensation. As the temperature increases and the fluid flows more easily the flow is controlled accordingly. The shock absorbing effect is therefore independent of the temperature. Öhlins shock absorbers provide the possibility for adjustment, making them adaptable to most vehicles, drivers and ranges of use. All of the shock absorbers, equipped with springs, have adjustable preloading of the spring action. The more advanced models permit individual adjustment of compression damping and rebound damping. WARNING! All vehicles are designed with a suspension geometry that includes wheel movements and angles. The changing of components can affect this and it is therefore essential that both the rear and the front ends match each other. Changing to Öhlins suspension gives optimum performance only when both the front and the rear suspension interact properly. 3 Compression flow Rebound flow 7. Shim stack Stop washer Shims stack 5. Flow through needle valve Piston 6. Flow through piston 8. Shim stack Function The function, in principle, is that fluid is forced through needle valves at a low rate of flow (Fig.5) and through a number of apertures in the piston at a high rate of flow (Fig.6). The flow through these apertures is regulated by shims (thin steel washers) that at high pressure are deflected to open for the fluid (Fig.7). On some models the needle valves can be set individually (illustration). By altering the size of the shims-stack (ie, number, thickness, diameter) (Fig.8) the characteristics of the damping action can be varied (this shall only be done by Öhlins authorized service workshops). Compression damping When movement of the vehicle causes compression in the shock absorber, the fluid flows through the needle valve (combined compression and return valve) in the piston rod. If velocity of the piston is high, ie, in the case of rapid compression, this will not be sufficient and consequently the shims underneath the piston will open to allow a greater rate of flow. The fluid that is displaced by the volume of the piston rod is forced into the external fluid chamber via a separate compression valve. Even this valve is fitted with shims that open at high piston velocity. The separating piston is displaced, thus increasing the gas pressure. Rebound damping When the spring presses the shock absorber out again, the fluid flows back through the needle valve in the piston rod. The fluid flowing into the chamber is forced by the pressure of the gas back into the shock absorber via a separate non return valve. If velocity of the piston is high, the shims on top of the piston will also open to allow the fluid to flow though. 4 9. Adjustment possibilities 10. ATV, steering by sliding Steering by sliding rear end Normal vehical steering by turning the front wheels in the intended direction 1. 2. 3. Settings Basic settings Always ensure that the basic setting made by Öhlins is correct. It is adapted to the specific make and model (in its original state) and for a rider of average weight. These adjustments are made to optimize the suspension: (Fig.9) 1. SPRING PRELOAD is when you adjust the spring to match your body weight and weight of your equipment. 2. COMPRESSION DAMPING controls how fast the shock absorber compresses when you hit a bump. 3. REBOUND DAMPING controls how fast the shock absorber returns to its normal position after it has been compressed. As an ATV has a rear axle without differential it is forced to turn mostly by sliding (Fig.10). Therefore excessively good road holding capabilities is undesirable. The rear end must be able to easily break loose to slide and the front wheels must not have too sharp turning radius, as this could cause the ATV to flip over. The tires are also a very important factor to the ATV's road holding capabilities. Pattern, sidewall flexibility and air pressure affects these characteristics. Changing the dimensions of A-arms, swing arm and linkage will also affect the vehicle's abilities. Because of this it is vital that the suspension is adjustable. Any change of components will demand different settings. To complicate the situation, the technique and skill of the driver will affect the perfomance of the machine. Therefore it is extremely hard to recommend specific settings. The best recommendation is to proceed by trial and error. However, good understanding of suspension design and function will give you the best chance to take advantage of the adjustment possibilities. This is why we only give basic and simple advice on how to set the dampers/shock absorber. Read the manual carefully and start your work. The Öhlins shock absorber will give you all possibilities for fine adjustment to fit you personal desire. WARNING! 1. ATVs are extremly depending on which kind of tires are beeing used. Soft versus hard tires can completely alter the road holding abilities. The suspension must be tuned in after each change of tires. 2. Every change in suspension geometry, i e change of a-arms etc, must be followed by new settings of the shock absorbers. 5 11. Measuring of ride height sag A B A B Preload Adjustment Setting the spring preload, adjusting procedures: By turning the rings on the shock absorber body you can adjust the springs tension to suit your weight. Hold the upper ring and adjust the lower one to the desired position. Then lock with the upper ring. To make this adjustment properly you must measure the ride height sag (Fig.11). Rear end 1. Lift the rear wheels up off the ground. 2. With the wheels off the ground, measure the distance from the top center of the rear axle to a point straight above it on the frame of the ATV. (A) 3. Wear all your riding gear. Sit on the seat with your feet on the pegs in correct riding position. Have someone to repeat the measuring procedure (B). The difference between the first and the second measurement ride height sag (A-B). 4. Adjust your spring preload so that your ride height sag is within the limits below or are according to the recommended settings in your Mounting instructions. Front end Use the same procedure to measure the sag for the front end. Adjust the spring preload to recommended settings. WARNING! Preload on the spring/springs is very important, because it affects the height of the vehicle and the wheel angles. Consequently, road holding characteristics can be changed, even negatively. NOTE! For very light or very heavy drivers, spring change may be needed to receive correct spring preload. 6 - + + + + = more damping = less damping 12. Rebound damper adjuster 13. Compression damping adjusters Setting the damping The adjusting possibilities of the advanced Öhlins shock absorbers facilitate fine setting. You can optimize adjustments to suit your own vehicles weight and equipment, your individual way of driving and the condition of the road. To be able to improve the road holding qualities it is of the utmost importance that you fully understand the functioning of the shock absorbers. Then you can learn by trial and error how they affect the vehicle. Depending on the model there are adjustments for rebound damping and compression damping. They have a normal right-hand thread. By turning clockwise they increase the damping action and counterclockwise they reduce it, see illustrations above. The knobs has definite positions with a noticeable "click", so it is easy to count to the right setting. Rebound damping action affects the characteristics of the vehicle most. The setting knob is located at the bottom on the piston rod (Fig.12). It can be adjusted in about 40 steps. Compression damping is set with a knob or a screw on top of the external reservoir (Fig.13). This can be adjusted in about 25 steps. Setting your vehicle NOTE! Always begin with the basic settings recommended by Öhlins. Always make notes, adjust in small steps and make only one adjustment at a time. Adjustments should be made in small steps (few clicks) at a time. By utilizing the adjustment possibilities you can test by trial and error, and learn how they affect your vehicle. Alway ...