shock rebuild, Showa, Air over

Discussion in 'The Garage' started by Ratman, Sep 5, 2008.

  1. OldPete

    OldPete Be aware

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    My hat's off to you Sir! :clap
    Did you work out the trailer brakes?

    The little Inspector General was keeping an eye on you. :lol3 (in the photo file)
    Hope she has grown well in these last few years.
    #21
  2. Ratman

    Ratman Lucky Rider

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    Yeah, prolly not many will, Dan, but I want to put the info down somewhere that will be public.
    I got an email from a guy in Europe who was putting an '80 750 twin (a model that we don't get in the USA) back together and he wanted me to rebuild the air, showa shock. I told him to find a mech that would use my instructions for the repair. So It's guys like that that may use the info.

    Before I went condo, I had a big shop with welders, lathes, mills, and the whole magilla...even a work bench. The bench was always full of old project messes, and I ended up working on the floor....nothing changes with me. :rofl
    #22
  3. Ratman

    Ratman Lucky Rider

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    Yes, I did....surge brake attached to the trailer tongue made from a fork tube and slider that actuates a front MC master cylinder which operates a rear brake caliper on each trailer wheel.
    #23
  4. Ratman

    Ratman Lucky Rider

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    I took the bike on a 120 mile test ride today. 80 miles of choppy Freeway at 70 to 80, 20 miles of fast curvy road, and 20 miles of tight twisties.

    Pretty happy with my shock. If I had it to do over, I'd try a little different inside grind. I accomplished the goal of making my Sabre much more comfortable. The harshness on small bumps is gone. I can barely feel little 1/2 in bumps on the freeway.

    I'll ride this one a long while before I bother to try a change. Might not ever change it as it's a lot of work.

    Before the change I'd go about 40 miles on the freeway, and the muscles that hold my back straight would begin to ache, and I'd be looking for a back rest. None of that today.

    I took 54 to I-8 then 67 to Dye near Ramona then did the twisties on Highland down to I-15 and then home on the freeway. It handles a little different in the twisties, but not bad.

    There is just a hint of not enough shock on some of the medium bumps/dips. I'm sure I'll get used to it. There's always a trade off. It's less of a canyon carver and more of a cruiser. That's what I wanted. :freaky
    #24
  5. MsLizVt

    MsLizVt pfft ...

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    Ratman, hi!

    Hope you don't mind me asking this, and hopefully I don't sound too naive, but did you grind down a specific spot on the inside wall of the shock to let the shock oil go by when the plunger/piston passes that spot?

    It's probably too late, but you wouldn't happen to have photos by any chance?

    Thanks, and again, hope that isn't too dumb of a question.

    Enjoy,


    Liz
    #25
  6. Ratman

    Ratman Lucky Rider

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    Someone said, "There are no dumb questions, Liz".

    I didn't know just where to grind the bypass grooves, so I had to start somewhere.

    I wanted the bypass to be in the neutral zone of where the shock rides on flat ground. Ideally the shock runs 1/3 third compressed, so I ground the groove an 1/8 inch before that one third point to 1/4" beyond the piston at that neutral point.

    That made a 3/4" long groove. In a shock wall that only has 1 5/8" of total movement.

    This will turn out to be a good technique for any bike that is harsh on small bumps. I think I'm onto a shocking breakthrough. Heh he...The pun was intended. :rofl

    I took the bike on a 120 mile test ride today. 80 miles of choppy Freeway at 70 to 80, 20 miles of fast curvy road, and 20 miles of tight twisties.

    Pretty happy with my shock. If I had it to do over, I'd try a little different inside grind. I accomplished the goal of making my Sabre much more comfortable. The harshness on small bumps is gone. I can barely feel little 1/2 in bumps on the freeway.

    I'll ride this one a long while before I bother to try a change. Might not ever change it as it's a lot of work.

    Before the change I'd go about 40 miles on the freeway, and the muscles that hold my back straight would begin to ache, and I'd be looking for a back rest. None of that today.

    I took 54 to I-8 then 67 to Dye near Ramona then did the twisties on Highland down to I-15 and then home on the freeway. It handles a little different in the twisties, but not bad.

    There is just a hint of not enough shock on some of the medium bumps/dips. I'm sure I'll get used to it. There's always a trade off. It's less of a canyon carver and more of a cruiser. That's what I wanted.


    Sorry, I didn't take pictures.....but if you're ready to do one for your bike....I could draw you a sketch. In fact I will draw a picture. Give me something to do. :evil
    #26
  7. Ratman

    Ratman Lucky Rider

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    Here's the sketch that I promised

    <table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/k1RCo9Bg3MOqap-UbMfpvNMTjNZETYmyPJy0liipFm0?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/-z9aqvXIOzSQ/UGziPoIZPDI/AAAAAAAAVTE/IzJijLeCXE4/s800/SAM_0315.JPG" height="600" width="800" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/105133432232392762779/DropBox?authuser=0&feat=embedwebsite">Drop Box</a></td></tr></table>

    Of course any other shock would have a different dimension from the end of the can where I have 1".

    Edited 2/15/14........ I think my earlier groves turned out to provide to much bypass. Now I'm only grooving 1/2" long grooves and doing 6 of them. I use a 1/4" stone and groove till the groove is 1/8" wide.
    #27
  8. MsLizVt

    MsLizVt pfft ...

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    Ratman, hi!

    That totally makes sense! Thank you for the explanation. It's pretty much how I had visualized it. Still think it's brilliant.

    My interest in shocks partly comes from hearing that a Showa shock for an 1100GS was not rebuildable. From what I heard, they made it sound like the shock was welded together and you couldn't even take them apart. Of course at the same time people would espouse how great the Ohlins are because they can be rebuilt. Well that wasn't good enough for me. I took a Showa apart. The issue isn't whether it can be rebuilt, but just sourcing the various seals.

    None the less, I read this thread a long time ago, and loved what you did. As a matter of fact, you inspired me to take that shock apart. Thank you for that! Now I'm loving this little modification you''re doing. Awesome!


    Liz


    #28
  9. Ratman

    Ratman Lucky Rider

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    Good for you. I've rebuilt a pair of spring over Showa rear shocks before. The ones I did were off an '80 Honda Magna. That's another bike that is way to harsh on the small bumps. It was harder to do, but would be worth it to fix this harshness thing.

    The Magna Showas, that I rebuilt, also had that plastic top out bumper inside that became dust and plugged up all the valve holes till the shock was seized up.

    Never be satisfied with what the factory gives you. Remember they are trying to make a product that fits everybody.....and we certainly aren't like everybody. :clap:clap
    #29
  10. Moparmanpete

    Moparmanpete The Cracken has risen!......again

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    Very nice!

    This week I'm going to try noodling a new rear tire on my scoot, like your 350. Had a valve stem rip out a few weeks ago, I was only doing 35 but what a wild ride! The bead unseated from the rim so I'm hoping it prevent that and the wild ride, and if I like it I'll do my XL next.

    Pete
    #30
  11. Ratman

    Ratman Lucky Rider

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    Mpmpete, I had slime in my rear tire on the CDR ride figuring that would seal leaks in case of??? Turns out the noodle which is supposed to be closed cell foam absorbed all the slime and came out of the tire about half size.

    I think I'd rather have the slime than the noodle with the tubeless set up. It looked like the slime was affecting the silicone that I sealed the rim with just at the edges.....might have been ok, though.

    ....but I dug the silicone seal out and switched to Shoe Goo (or Seal All) for the new tire with slime. If I have any rim bead leaks, I push the tire away from the rim at those point and put silicone seal in the leak area and then blow it up till I don't have leaks.

    I just spent three days in Death Valley. One of the riders that I was with wore thru a tube from running low air pressure. I again motored on by. Loving my Tubeless tires.
    #31
  12. Ratman

    Ratman Lucky Rider

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    I rode my Sabre up to Lone pine over the weekend....it only amounted to a little under 500 miles, but that was enough to include most kinds of road surfaces.

    My last shock alteration has taken 90% of the small bump hammering out of the rear end/wheel. It's no longer necessary to wince in anticipation when I see a bump coming.....wish I'd figured that change out 15 years ago.

    <table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/bQYUEXQiqWK1FPPPZZYpjtMTjNZETYmyPJy0liipFm0?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/-yyhfYJMCTr0/UIoAae3s0PI/AAAAAAAAVgo/xczlbQVdqDk/s400/SAM_0551.JPG" height="182" width="400" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/105133432232392762779/DVOct201202?authuser=0&feat=embedwebsite">DV Oct 2012</a></td></tr></table>
    #32
  13. Dessert Storm

    Dessert Storm Dances With Drunks

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    Excellent thread, Ratman; thanks for your trouble taken to explain and photo the process. :clap

    Have you ever seen this thread, from Goldwingfacts.com forum?

    http://www.goldwingfacts.com/forums/2-goldwing-technical-forum/394579-gl1100-rear-shock-rebuild.html

    Post #8 is interesting. If I've understood correctly, the poster has used thinners to dissolve in-situ the disintegrated bump-stop. Or am I barking up the wrong tree?

    Any reason this could not be done without dismantling the shock?

    Have I understood correctly that you have ridden without problems with no bump-stop? If that is the case, I'm wondering if a flush with thinners then a recharge with new oil might see at least some 'dead' airover shocks restored to life without open heart surgery!

    Be interested to hear your thoughts.

    I should give also the poster on the 'wing forum credit for his work and the trouble taken to post. He is a guy called willwilly. If by any chance you read this, thank you dude.
    #33
  14. Ratman

    Ratman Lucky Rider

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    Yo, Desert Storm, glad that someone has a use for this old technology. Speaking of this Shock work I had a 1000 mile ride last week and decided that I had too much Bypass in the last shock change a few months ago.

    So I'm building another shock that has less bypass....and while I was doing it I took a picture of the mod that I put in this shock. I'd estimate that I have 1/2 the amount of bypass in this new shock.
    <table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/DIaTaC3NZR_eQqWfjxKt8NMTjNZETYmyPJy0liipFm0?feat=embedwebsite"><img src="https://lh4.googleusercontent.com/-b6_8-wee3mg/UZ59fc5MZYI/AAAAAAAAZSY/M4Wf2gp_Tfo/s800/IMG_0763.JPG" height="763" width="800" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/105133432232392762779/ShockRebuild?authuser=0&feat=embedwebsite">Shock rebuild</a></td></tr></table>



    I found a broken bottom out bump stop in the shock that I replaced with a piece of KYB bumper on the right.
    <table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/qscSczjZngVQ_4_VuWkzr9MTjNZETYmyPJy0liipFm0?feat=embedwebsite"><img src="https://lh6.googleusercontent.com/-XfqVMj28LGU/UZ554X4W8fI/AAAAAAAAZR4/KU7ApEdoy7w/s800/IMG_0761.JPG" height="560" width="800" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/105133432232392762779/ShockRebuild?authuser=0&feat=embedwebsite">Shock rebuild</a></td></tr></table>

    <table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/pArJg6NAQTJhqGrdKVsIXNMTjNZETYmyPJy0liipFm0?feat=embedwebsite"><img src="https://lh3.googleusercontent.com/-lOOgHShAACc/UZ5544lZ0xI/AAAAAAAAZSA/TL6kNH-iy2c/s800/IMG_0762.JPG" height="436" width="800" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/105133432232392762779/ShockRebuild?authuser=0&feat=embedwebsite">Shock rebuild</a></td></tr></table>

    ....and while I'm working on the newer shock, and since you can't get new seals for these bike's shocks (V65 Sabres), I've been reclaiming the seals that come out of the shock. Here's a Video of how I sharpen that seal lip...very simple, actually. Works good on Fork seals as well.
    http://www.youtube.com/watch?feature=player_detailpage&v=P2AlMNeuk3w
    #34
  15. Ratman

    Ratman Lucky Rider

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    I made a 3000 mile trip to Co and back to SD Ca this Summer using the latest bypass shock alteration. I was very pleased with the ride.

    .....but I thought that for comfort (not speed in the corners) I'd like to try a lighter spring in the shock.

    I looked around at other moto spring. The stock V65 Sabre spring is 7 coils of a .506" wire spring about 7" long....non progressive wound

    I looked at the ST1100 rear shock spring and found that to be about 10 coils of a .430" spring about 10" long....progressive wound. I thought that that might work.

    I found some spring constant calc software on the net. Some ciphering came up with that I should cut that spring down to an 8.75" length. I cut it down on the progressive wound end and heated and flattened that end, then ground it to make a square end to the spring.

    I didn't have much faith in the numbers, but what you going to do? You have to try it to see how it works on the bike.

    Anyway I put it on the bike. Surprisingly, the spring length gave the proper preload and ride height to the bike, and softened up the last of the harshness that I'd been complaining about.

    The upshot of all this is...that if you have a bike that is too harsh on paved roads....It needs some bypass in the shock at the neutral ride height, and it needs a longer, softer spring to finish off a nice ride improvement.

    I wish I had tried just the spring change before the internal valve bypass so that I know how it would ride with just the Spring alteration. Maybe I'll get a chance to do that one day. :freaky
    #35
  16. Ratman

    Ratman Lucky Rider

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    Dustin messaged me about a year ago with some shock rebuilding questions....and then a year later after running the bike for a few months. I thought posting his results might encourage some others to try this shock repair.

    [/QUOTE]

    And a year later after some riding Duston say.........

    #36