790 Adventure R Suspension Mods

Discussion in 'Parallel Universe (790/890)' started by windblown101, Jul 5, 2019.

  1. SoilSampleDave

    SoilSampleDave Dr. Zaius was right!

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    How do you weight all geared up? Be nice to know if your shin changes would work for my weight. Thanks
    #41
  2. TrailTrauma

    TrailTrauma Nemophilist Supporter

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    It may...do you think you could stay on @AdvRonski 's 6 at his pace though?
    #42
  3. SoilSampleDave

    SoilSampleDave Dr. Zaius was right!

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    Probably not, but the changes he made helped with plushness on chop; so it will be better than stock regardless.
    #43
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  4. AdvRonski

    AdvRonski They call me......Ronski

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    I weigh 168# without gear, and I've never really piled up all of my gear and weighed it. Probably 20-25#, depending on the day's selection. Anyway, I'm working with @Torque, to develop settings that will be quite an improvement, even over my setup, so stay tuned for how that develops.
    #44
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  5. Torque

    Torque Been here awhile

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    I believe the shock on the 790 is a 46mm like the 1090s and exc's. The springs off the 1090's are 60mm id. Am I missing something?
    #45
  6. AdvRonski

    AdvRonski They call me......Ronski

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    George, I will have to double-check the ID of the rear spring when I crack the shock open again, but I remember sliding a 62/63 spring onto the shock to check it's fit, and it looked good. But then, I wasn't really that focused on that aspect of the project at the time.
    #46
  7. SoilSampleDave

    SoilSampleDave Dr. Zaius was right!

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    I think 60 vs 62 would be hard to tell that way. No calipers handy?
    #47
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  8. Torque

    Torque Been here awhile

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    Mailed shims yesterday by the way Ronski. Added a face shim to the shims, as I mentioned the WP oem stacks will bend the face shims in short order.
    #48
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  9. AdvRonski

    AdvRonski They call me......Ronski

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    All right, George, I received the shims and I'm going into the shock today. I measured the spring ID at 58/60, so at least that is clear now.
    #49
  10. Noneking

    Noneking Been here awhile

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    #50
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  11. Torque

    Torque Been here awhile

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    Good, I will order up a dozen or so variable rate springs for the 790.
    Remember we also need the shim stack in the compression valve to analyze.
    Thanks!
    #51
  12. Torque

    Torque Been here awhile

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    So AdvRonski has increased his shock travel by 5mm. That will equate to about 15mm or over 1/2" of additional travel. So to keep the bike in the same attitude regarding level the forks will have to be lengthened. On this bike the angle of the forks at 63 degrees would necessitate lengthening the forks by 15mm plus 11% so total of about 16.65mm. Small amount but when sliding forks up and down in the triples 2mm is definitely a noticeable change. We will have to measure the actual ratio of the rear shock in the beginning of the stroke in particular to confirm the 15mm. Just thinking out loud here.
    So the guys that are shortening a bike two inches, or going to 300mm that 11% fork info can be important.
    #52
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  13. Torque

    Torque Been here awhile

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    Rant: Although the above is pretty straight forward, I have said it before and will say it again. There are suspension engineers and tuners that are so knowledgeable. If I put out any info that is incorrect, please pipe in help us understand as many of us want to learn every day!
    I do not like unsubstantiated info communicated as fact. It does nobody any good, and sometimes turns into group think, then it does not matter if it is fact.
    #53
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  14. AdvRonski

    AdvRonski They call me......Ronski

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    As an update to the joint suspension project with @Torque, I just completed a shock revalve with @Torques shim stack specs. This Guy knows his stuff! He went in a whole other direction from the approach I was taking, and the results are awesome. I went out for a good, hard ride out in the desert singletrack, with whoops, ditches, jumps, and big rollers. It just ate it all up, and asked for more. I was able to push much harder than I could on the 950, actually much closer to the level of the 350. If you like your 790 now, you will love it with great suspension! This is just Phase 1 of this project, the forks will be next, and then a progressive-rate rear spring to fine-tune the rear shock action.
    BTW- @Torque does have a secret identity, he is George Spinali of Suspension 101 in the San Diego area. I've always heard good things about his work, and now I know why.
    IMG_20190808_143101.jpg
    #54
  15. TrailTrauma

    TrailTrauma Nemophilist Supporter

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    Hey guys. I wanted to run the rudimentary steps I've taken in an effort to get my front and rear sags done by you. There may be details I've overlooked and this thread might be the best place to ask for advice if I have.

    * Lifted the bike and zero'd out my sag gauge.
    * Using a tape measure I measured the exposed lower fork tube and got 267mm
    * Sat the bike down
    * I didn't mess with the fork pre-tensioners because they were already sitting at 0.

    I had my extremely patient wife take level photos of the sag gauge with me sitting forward as I normally ride, as well as standing in an aggressive posture.

    *Sitting = 89, standing = 85

    Next I repeated the sitting/standing postures while my wife snapped photos of the new lengths of the exposed lower fork tube.

    *Neither posture seemed to impact the results much - both revealed ~200mm, from the initial, fully extended 267. *I bounced several time to overcome stiction, prior.

    So can I take this to mean my front sag is 67mm? (267mm-200mm) OR is there another more standard approach?

    Also, looking at the average of my rear sag [(89+85)/2]=87mm, I looked at what percentage that was of the bikes 240mm travel and it's ~36%. Am I supposed to then apply that to the front forks as well? Because I figure I am in some manner but am not sure if my approach was correct (measuring exposed lower fork tube).

    In other words, am I trying to achieve 87mm of front sag as well to balance front to back? IF thats the case it looks like I need another 20mm of front sag. Do I get there by lifting the bike again and turning the pre-tensioners counter-clockwise?

    I really want to get this sag sorted out well before I ever touch the clickers.

    Edit: For reference sake, I'm 220 without gear. Today I didn't weigh myself, but I threw on my Klim Badlands Pro pants & jkt, 3L filled Kriega hydro pack, helmet, Tech 7 boots, and I placed my usual loaded 20L Kriega rear bag on the back of the bike (tools, hammock, clothes etc).

    Thanks for any insights you guys might have.
    #55
  16. [Art]

    [Art] Been here awhile

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    #56
  17. AdvRonski

    AdvRonski They call me......Ronski

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    Art- in method 1, the math would only work out if L1 was the total amount of wheel travel-which it is not. It is just the distance from the axle to a measuring point. So, you have to know the amount of wheel travel, then adjust preload until the difference between L1 and L2 is about 1/3 of the wheel travel.

    Method 2 is a pretty standard procedure for dirt bikes, with 300mm of wheel travel, but those figures will not work for just about any adventure bike. Static sag is problematic for heavy bikes, as the rider weight is a much smaller percentage of the overall bike/rider weight, so a meaningful ratio to race sag is going to be widely variable.
    #57
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  18. Gaulin

    Gaulin Orange (& Blue) Crush

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    Hey TT,
    I think Ronski nailed it in his above post:
    I didn't think of this when we were talking sag procedure previously. He has a great point that explains why my sag values aren't very far off yours being around 180 w/o gear.

    So those sag setting values in the manual that seemed crap and arbitrary to me, make sense now. Doesn't matter unless you're hauling a campsite worth of gear with you, and you'll likely need some more preload.

    My vote is you're likely in an ok range as-is, there's no adjustment to be, or can be made as you're already all the way backed off on fork preload, and the rear sounds reasonable.
    #58
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  19. [Art]

    [Art] Been here awhile

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    #59
  20. SoilSampleDave

    SoilSampleDave Dr. Zaius was right!

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    I don’t believe there is a great way to measure fork sag, or it would be as well known as how to set the sag for the rear. If I’m not happy with the stock spring rate, I just try what a reputable suspension shop suggests for my weight. If it feels too stiff or too soft, then go down or up one spring rate. Never had to change more than one rate from suggested.
    #60