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Is my rear damping adjustment shot?

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    Is my rear damping adjustment shot?

    It's spring yay! Apart from some spit and shine, I've tweaked the suspension a bit. I thought harder and stiffer made the bike corner better, but setting the fronts to softest damping made it notably less nervous in corners, removing a slight tendency to fall in. (I suspect that will be even better with fresh tires.) Naturally more comfortable over a bump too. A bit vague and wallow-y sure, but not more than it needs to. Will try softer preload as well, I can't twist the preload adjusters without loosening the fork caps it seems.

    But to the point! My rear shock! The preload seems just fine, the little red ball goes up the scale as you twist and spring seems to firm up, I haven't tested much. But the damping adjusting knob seems very strange and I'm pretty sure it's not working.

    Found a crack where the adjustment cable meets the shock:




    The knob seems to do very little other than rattle with varying resistance to turning, check out this videoclip: http://www.youtube.com/watch?v=FQPQDTSMMSU

    The front damping adjusters turn with very solid and satisfying clunks between settings, is the rear supposed to be like that too? Is a new cable all I need?

    As thanks, some regrettably poor cell phone snaps of a short coastal cruise in the warming spring sun.




    #2
    Those cables all seem to crack there, mine did. Pull the cable off and soak it in some diesel to clean it up. That is unless it has unwound, but I doubt it. If all is well with it lube it and use a piece of fuel hose over the break and clamp each end with small hose clamps to strengthen the break. I would go ahead and pull the shock off and inspect the gear and the moving parts of the adjuster within the shock. You have a small pinion gear on the end of the cable, a ring gear with a peg sticking out of it, and a valve in the shock that spins to change the damping with a peg on it. Sometimes those pegs corrode and fall apart so the knob does nothing. You can spin the valve in the shock with a small screwdriver to change the damping setting. There is a red dot on the valve that denotes position #1. There is a rubber plug you remove to view that.

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      #3
      Thanks for the tip. The rattling sound comes mostly from the adjuster itself, it can jump out of gear there too right?

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        #4
        Originally posted by Ola View Post
        Thanks for the tip. The rattling sound comes mostly from the adjuster itself, it can jump out of gear there too right?
        Thinking about this more the ring and pinion is at the upper part of the cable. On the lower end you have a cam against cam, little drums with a peg on each. One is on the cable end and one in the shock. Just pull the cable and you'll see what I mean. You can get away without pulling the shock by getting your head down and look into the shock where the cable goes. Pull the rubber plug to find the red mark for #1. You may have to pull the rear wheel to get a good look.

        I don't have my stock shock on the bike anymore so I forgot exactly how the cable was set up.

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          #5
          If that's the original shock on your bike, does turning the dampner still result in any changes?

          There is a point where firmness and compliance meet to produce the ride you want
          1978 GS 1000 (since new)
          1979 GS 1000 (The Fridge, superbike replica project)
          1978 GS 1000 (parts)
          1981 GS 850 (anyone want a project?)
          1981 GPZ 550 (backroad screamer)
          1970 450 Mk IIID (THUMP!)
          2007 DRz 400S
          1999 ATK 490ES
          1994 DR 350SES

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            #6
            Turning it did nothing. I opened it up and figured out why, the driven plastic gear attached to the cable was chewed to pieces. That driving gear looked ok, although it was snapped loose from the adjustment knob and twisted many times around. They still stick well enough together to transmit force. The shock-side gear might be stuck too, but I didn't go that far. The ride is decent enough to leave as is for now, it'll get a repair or a replacement when time comes, thanks for the input guys.

            What's the #1 recommendation among the aftermarket shocks? I'd like something that is actually progressive, i.e. comfy on bumps but firm on cornering but are those big $$$$?

            Comment


              #7
              Originally posted by Ola View Post
              Turning it did nothing. I opened it up and figured out why, the driven plastic gear attached to the cable was chewed to pieces. That driving gear looked ok, although it was snapped loose from the adjustment knob and twisted many times around. They still stick well enough together to transmit force. The shock-side gear might be stuck too, but I didn't go that far. The ride is decent enough to leave as is for now, it'll get a repair or a replacement when time comes, thanks for the input guys.

              What's the #1 recommendation among the aftermarket shocks? I'd like something that is actually progressive, i.e. comfy on bumps but firm on cornering but are those big $$$$?
              Even new the stocker wasn't all that great. To me it seemed oversprung and underdamped when new and as the spring softened up needed more and more preload. Even on 4 the damping didn't seem to end the tendency to pogo on sweepers. I got lucky and got a practically new Works Performance Durasport with remote reservoir for $150 in the classifieds here. Only time I've ever seen one pop up for these bikes. Works is probably the best choice all around when you weigh price and performance.

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                #8
                It's a cog arrangement on the shock end. 1 pin sticking out of each of two rotating pieces perpindicular to each other.

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                  #9
                  My bet is on the little plastic gear at the knob end. Mine went last fall and sounded just like that. By weight its the most expensive part on the bike!

                  /\/\ac

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                    #10
                    FYI ...it is easy to recharge the hydraulic preload adjuster, they tend to leak down over the years and the master piston bottoms before full stroke on the slave.
                    GSX1300R NT650 XV535

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                      #11
                      My cable is fine, but the little gear up top is stripped. you can pull out the rubber plug on the shock to see if the damping adjustment still works.
                      I don't think the gear is still available.

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                        #12
                        After thinking about the arrangement of the damper adjuster a bit more I realized I gave a bit of bad info. It all works the way I described, but there are 4 pins on the piece in the shock that is part of the damper valve. One pin for each position. The piece that is on the shock end of the cable only has one pin.

                        That is my final answer.
                        Last edited by Guest; 03-14-2009, 11:25 AM.

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                          #13
                          Final answer accepted! I'll probably postpone the adjuster fix, but what I can do is open up the connection and change the setting manually on the shock.

                          I swung a leg over a BMW F800ST today....very tempting. But my wallet let out a sad whimper, so upgrading what I have is probably better.

                          Comment


                            #14
                            Originally posted by Ola View Post
                            Final answer accepted! I'll probably postpone the adjuster fix, but what I can do is open up the connection and change the setting manually on the shock.

                            I swung a leg over a BMW F800ST today....very tempting. But my wallet let out a sad whimper, so upgrading what I have is probably better.
                            Yes, you can spin the adjuster inside the shock to change the damping setting. Just use a small screwdriver to spin the pins.

                            Comment


                              #15
                              Originally posted by Clone View Post
                              My cable is fine, but the little gear up top is stripped. you can pull out the rubber plug on the shock to see if the damping adjustment still works.
                              I don't think the gear is still available.
                              I just bought one last Fall via cycle-parts.com. I think it was about $10-11, PN# 62356-31340

                              /\/\ac

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