Note: Before rebuilding or re-valving your QA1 shock absorbers, your work area must be clean.  Shock absorber performance is greatly affected by any contamination (i.e. dirt, dust, rag lint, tec.).
 

TOOLS NEEDED FOR REBUILDING AND REVALVING

• Vise with soft jaws (aluminum or plastic)
• Spanner wrench
• Torque wrench with 17mm or 11/16" socket
• Pick set
• Shock Oil
• Rebuild kit and/or re-valving kit
• Vavling Table
• Diagram of Shock
• Instructions Listed below

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The Valving Table lists each of the components you need for each valving.
File Size: 2 Pages - 8 KB

This diagram shows all the components of the shock absorber.
File Size: 1 Page - 946 KB

1. Check shouck mount bearings for excessice play, replace as needed.
2. Clamp shock body eyelet in a vise with shaft pointing up.
3. Fully extend shock rod from body.
4. Using a spanner wrench, unscrew the closure nut.  Use a pick tool to remove the closure nut o-ring.
5. Remove shock rod assembly, gland, and compression (inner) tube by pulling up on the shock rod.
6. Remove foam from shock and set aside in area where it will not collect debris.
7. Gently tap the gland and shaft assembly away from compression tube, this should be done over a drain pan.
8. Pour oil from shock body and compression tube, watch for any debris in the used oil. Clean the parts with mild solvent as necessary and set aside.
9. Clamp piston-rod eyelet ( or stud-top) in a vise with the piston pointing up.
10. Cover gland with rag, blow compressed air into gland side-bleed hole to pop the piston-rod seal out of gland.
11. Remove 17mm nylock nut to access piston valving and remove gland and seal to replace internal gland o-ring.
12. If not re-valving, the rebound stack, piston, and compression stack need to be kept in its original order for re-assembly.
13. Remove the rebound bumper, gland assembly, and piston-rod seal from the rod.

ASSEMBLY

1. Use pick to remove gland internal o-ring and replace with new o-ring (thinner cross section). Be careful not to nick gland bushing. Inspect bushing for wear, and replace gland if bushing is loose on shaft.
2. Reassemble shaft with travel indicator, closure nut, piston-rod seal (do not push into gland yet), gland assembly, and rebound bumper .
3. If re-valving, read re-valving instruction section first.
4. With shaft still in the vise, assemble the compression valving, piston, and rebound valving. The compression valve stack is on the bottom of piston and the rebound valve stack on top. It's important that the piston is positioned with letter 'R' facing up.
5. Torque 17mm nylock nut to 20ft/lbs (240in/lbs). Check nylock nut for any loose burrs and remove as necessary .Set piston rod assembly aside.
6. Place the shock body in the vise, holding it by the lower mount.
7. Pour ' 1/4 cup of oil into the shock body.
8. Gently insert the compression tube and foam into shock body, base valve first.
9. IMPORTANT! Do not tear the foam or pinch it under the base valve.
10. Fill shock body and compression tube with shock oil to just below (1/16") the top of the compression tube.
11. Move compression tube around to free any trapped air bubbles.
12. Insert the piston-rod assembly, with piston wrap, into compression tube.
13. With the piston assembly submerged approximately 1 ", tap shock rod eyelet with a soft mallet. This opens the compression valve stack to release any trapped air bubbles.
14. Use your fingers to hold the compression tube down and raise the shock shaft until the piston is approximately 1/2" from the top of the compression tube.
15. Hold shock shaft near the top of the compression tube and slide the gland into the shock body. Oil should come up through the gland's bleed hole. NOTE: Remember we are attempting to build a shock without any air trapped inside.
16. Holding gland down, cycle the piston rod in short 1 " strokes. Under full extension, the gland bleed hole should not be allowed to pull air back into the shock. Add more oil as necessary .
17. Keep shock fully extended and slide the rod seal into the gland. Push the closure nut o-ring into the outer groove of the gland.
18. Install and tighten the closure nut.
19. Invert the shock and wipe off any oil over-flow.
20. Stroke the shock and check for smooth operation. Rough or jerky movement indicates that air is trapped inside - repeat the steps above.

Shock absorbers create dampening by flowing oil through restrictive paths, the more restricted the flow- the higher the dampening force. Nearly all shocks use a combination of "bleed passages" and "blow-off valves" to control the oil flow in both compression and rebound separately.

Bleed is typically controlled by the size of a small hole(s) or slit(s). The oil can flow easily at low shaft velocities, but as velocity increases -the resistance rises progress- ively. QAl shocks use a single bleed hole in the piston, which ranges from .033" to .059". Smaller or larger bleed holes may be used to raise or lower low-speed dampening.

Blow-off is typically controlled by either a spring pushing on a valve, or a set of disc valves covering a set of larger holes. Once the shaft reaches a certain velocity , the valves will open- allowing a linear or digressive dampening curve. QAl shocks utilize three sets of disc valves, two for compression and one for rebound. One rebound valve- stack and one compression valve-stack are on either side of the piston, the other compression valve-set is in the base valve. For simplicity, there are only two base valves used, one for compression valving 6 and below. and one for 7 and above.

The following trends will help you tune your QA1shocks

LOW SPEEDLO~2 in/sec):

The piston bleed hole size has the main effect. Larger bleed holes will lower the low-speed dampening - and will delay the blow-off to occur at a higher velocity .Smaller bleed holes will raise the low-speed dampening - blow-off will tend to occur at lower velocities.

MEDIUM SPEED (2~10 in/sec)

Valve stack begins to open. The disc closest to the piston (1.300" OD) will have the main effect. Valve stack thicknesses determine the blow-off velocity and the slope of the dampening curve. Bleed can affect the blow-off velocity, but the slope of the graph remains the same. The blow-off can be more or less distinct depending on the amount of bleed.

HIGH SPEED (> 10 in/sec ):

The shape of the valve stack has main effect. Thickness, outside diameters, and number of discs determine the shape of the valve stack. The smallest disc (0.700" OD) acts as the pivot disc. The pivot disc has a large affect on the higher speed portion of the dampening curve as it controls the diameter where the rest of the discs start to bend. Removing the 0.700" pivot disc will create a more digressive valve curve.