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    #16
    Pressure

    OK I will bone them a bit more and see if it is sensitive to that.

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      #17
      My bikes have 28 - 32 written on them with 28 36 for two up or continuous high speed from memory.
      I ran at Suzuki's spec for a while but then switched to Avon's & have noticed some improvement, better & more stable turn in being one of them.

      I would think your bike has to be roughly the same weight as mine, tyres are the same size so..... The sport Demon's can't be that different. I think 42PSI is the max recommended for the Avon by the way. The rear has a 650lb spec from memory at that pressure.

      Dan
      1980 GS1000G - Sold
      1978 GS1000E - Finished!
      1980 GS550E - Fixed & given to a friend
      1983 GS750ES Special - Sold
      2009 KLR 650 - Sold - gone to TX!
      1982 GS1100G - Rebuilt and finished. - Sold
      2009 TE610 - Dual Sporting around dreaming of Dakar.....

      www.parasiticsanalytics.com

      TWINPOT BRAKE UPGRADE LINKY: http://www.thegsresources.com/_forum...e-on-78-Skunk/

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        #18
        I run 16-14.



















        In the dirt.

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          #19
          Originally posted by posplayr View Post
          I appreciate you comments, but I'm confused about the last one.
          I guess I never elaborated, did I? You want about 10-15mm of static sag combined with around 30mm of laden sag. If you cannot get those two numbers with one setup, then your spring rate is not right.

          Lots of static sag with correct laden sag = too stiff of a spring rate

          Minimal static sag with correct laden sag = too soft a spring rate


          Mark

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            #20
            do a simple experiment and install your old shocks and see what happens.

            i was have all sorts of weird handeling issues on the sv until i set up my preload using the ohlin guide. you want the front and rear to be in the same 1/3 of the ranges that ohlin lists

            here is my sag spread sheet, you can see my progression to get the front and back to balance out.
            Last edited by first timer; 04-21-2009, 10:28 PM.
            78 GS1000 Yosh replica racer project
            82 Kat 1000 Project
            05 CRF450x
            10 990 ADV-R The big dirt bike

            P.S I don't check PM to often, email me if you need me.

            Comment


              #21
              Sag Sheet

              Ryan,
              So I get the general idea on your spreadsheet, but a couple of questions:

              1.) You were only changing preload front and back when you did this?
              2.) Did you do one adjustment at a time?
              3.) What were the changes between columns?
              4.) Several of the steps seem to have been in range of the Ohlins guide; What ratios/distances were you trying to achieve in the end?

              I know that I have not measured the ride height of the front and it has 14mm of preload with the progressive springs. I think It was Joe Nardy that had his blue ED the same way so I just left it that way as I figured they knew better than I.

              However now that I'm in a better position to judge, it is entirely possible the 14mm on the front is too stiff in comparison to the rear shocks. As a result the rear is getting more weight shift to it and loading the rear tire more than it should.

              I guess I need to measure the front suspension numbers, more than likely I will have to go and cut that 14mm length (due to the racetech emulator) That way I can adjust the front preload which now is at minimum.

              If I were to put my rear shocks back to where I got them from Ohlins, they would probably be 12/28mm which compares directly to your 13/28 on the (SA/RH)rear. The issue is likely the stiff front.

              Jim

              Comment


                #22
                You were only changing preload front and back when you did this? – yes that all there is, J I did front and back

                Did you do one adjustment at a time? – No, you can’t both adjustments effect each other.

                What were the changes between columns? –

                F1 = front end full extended
                R1 = rear fully extended

                F2 = front end loaded statically, no rider
                R2 = rear end loaded statically, no rider

                F3 = front end loaded with rider in gear
                R3 = rear end loaded with rider in gear

                R sa = rear static sag = R1-R2
                F sa = front static sag = F1-F2

                R ra = rear rider sag = R1-R3
                F ra = front rider sag = F1-F3

                Without rider (static sag):
                Rear 10-20 mm (r1-r2)
                Front 15-30 mm (f1-f2)

                With rider (ride height):
                Rear: 25-40 mm (r1-r3)
                Front: 35-50mm (f1-f3)

                My setting I settled on was:
                13mm R sa – close to the middle range
                24mm F sa - right in the middle of the range

                28mm R rh – in the middle of the range
                34mm F rh – just a touch out of the range on the stiffer side

                It can be hard to get everything set right, the best you can do is shoot for the middle range on everything and try to get as close as you can, usually you end up just trying to get everything somewhere in the range and be happy with that (its becomes harder when your front and rear springs have different rates or are progressive)

                As a foot note these measurements can’t be done without a friend and front and back bike stands.

                I am not sure try doing some measurements with the spacer you have now and see if you fall in the ohlin ranges
                Your front end has some preload adjustment to, don’t forget that. And see if that helps or makes it worse.

                You basically have to dive in and start fiddleing, you will get the hang of it, and you don’t have to be to anal about things as long as they are in range, these settings can be so sensitive that if you eat a burger then you sag could be thrown of a mm or 2.

                Best tip I can offer is bust out a laptop and a quick excel spread sheet that will do the calcs for you, makes it quick.
                78 GS1000 Yosh replica racer project
                82 Kat 1000 Project
                05 CRF450x
                10 990 ADV-R The big dirt bike

                P.S I don't check PM to often, email me if you need me.

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