Leading link tube sizes

Discussion in 'Hacks' started by sidecarcrazy, Oct 21, 2013.

  1. sidecarcrazy

    sidecarcrazy grandad in gladstone

    Joined:
    Jun 12, 2006
    Oddometer:
    186
    Location:
    Aussie Land
    Been looking through the leading link thread for the following info & can not seem to find it.
    I need the info for a set of LL for a K1100 ie:
    Tube type to buy
    Outside diam will need to be resized to 41.35 mm
    Tube wall thickness ?
    That is all the info I need please if someone can help me ?
    An old fart in Australia
    #1
  2. 3legs

    3legs Real men ride sidecars

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    Oct 3, 2007
    Oddometer:
    1,184
    Location:
    Adelaide,South Oz
    I use hollow bar on my k1100. It's smaller than the OD of the original but I get sleeves made up and weld the sleeves to the bar. When I get time I will try to get accurate dimensions for you but from memory the bar is 6mm thick and about 33 mm od. It's heavy but it won't break.

    3legs
    #2
  3. jaydmc

    jaydmc Long timer

    Joined:
    Sep 26, 2008
    Oddometer:
    1,111
    On our leading links we start with 1.5 inch .120 wall DOM tubing, we slide a 1.25 .120 wall DOM tube down the center before bending making for a double wall. We then machine sleaves for the triple tree's but taking 1.75 .120 wall DOM tubing and machining the O.D. the same as the fork tube on the bike. Once machined down we put a slit in the sleaves and use them as shims. For us this works well as our tooling is all set up to work with these sizes so our down tubes can be made the same for all of the different leading links we build making it possible to use much of the same tubing.
    Jay G
    DMC sidecars
    www.dmcsidecars.com
    866-638-1793
    #3
  4. arbalest

    arbalest Adventurer

    Joined:
    Mar 19, 2009
    Oddometer:
    60
    Sidecarcrazy,

    The measurement you have is correct, but a little misleading. I needed very short tubes between the triple trees on my K100, and 1 5/8" is as close to perfect as you'll find.

    arbalest
    #4
  5. FR700

    FR700 Banned

    Joined:
    May 4, 2007
    Oddometer:
    8,512
    The 1100 runs slightly larger diameter tubes than the 100.

    Also the 1100's run a different design of triple trees. The lowers are a gull design and each clamp point ( all four ) has two pinch bolts.
    Between the gull spreading the clamping distance and the extra bolts they are a superior design.

    Even the bar risers are spread further apart to take away that sensation of the bars twisting in the bushes.
    #5
  6. claude

    claude Sidecar Jockey

    Joined:
    Mar 17, 2002
    Oddometer:
    4,162
    Location:
    Middleburg, Pa. (Snyder County)
    Using stock triple trees we use 1 1/2 x .120 wall with 1 1/4" x .120 inside as Jay mentioned. The spacer sleeves are machined to fit inside the triple trees and are split to allow proper clamping. We do not weld the sleeves to the tube but do them with a lip on them to locate them properly. This basic idea is not a new design by any means and has been effectively used on various leading link systems over the years. Not saying that 1 1/2 " etc are THE trick sizes to use but these sizes work with most applications. Some have argued that the double wall design is better than a single heavy wall tube.
    Depending on tire/wheel etc. widths the tubes may be splayed apart for wheel travel and clearance.
    Down tubes should be connected together, we feel, for total rigidity of the assembly.
    #6
  7. sb_250y

    sb_250y Safari Finisher 2011

    Joined:
    Sep 3, 2008
    Oddometer:
    172
    Location:
    Blue Mountains
    A popular fabricator in Australia used:

    upper fork legs- ASSAB 750V 45/20 Hollow Bar.

    on his leading links.
    #7
  8. sidecarcrazy

    sidecarcrazy grandad in gladstone

    Joined:
    Jun 12, 2006
    Oddometer:
    186
    Location:
    Aussie Land
    Thank you sb_250y that is the info I am after.
    Now, because I live in rural South Australia, who knows where I can by 2 pieces of this tube each 1 meter long and have it posted to me ?
    Or an address & phone number in Adelaide & I can go down & buy it next time I am down there.
    Or buy it for me & post to me, can pay via bank deposit/transfer, credit card & Paypal.
    Waiting for reply

    PJ
    #8
  9. sb_250y

    sb_250y Safari Finisher 2011

    Joined:
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    Oddometer:
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    Location:
    Blue Mountains
    #9
  10. 3legs

    3legs Real men ride sidecars

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    Location:
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    Yep. That's where I bought mine from. The were opposite the Pooraka fruit markets on diagonal rd. From memory didn't cost that much. Around $35 metre (although that was around 5 years ago).

    3legs
    #10
  11. bbjay

    bbjay Been here awhile

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    Jun 1, 2009
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    431
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    Frankston

    PJ

    I have a account with bohler steel ,, If you ley me know exact size you want i can get you a price ,, The 750v is the steel i used for my strom fork legs ended up around 7m/m thick after machining they were heavy but stronger that way

    Bernie
    #11
  12. bbjay

    bbjay Been here awhile

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    PJ

    just looked on my tube chart for 750v and 45o/d and id either 32/28/20 dont quote me on that i would have to check with bohler

    B
    #12
  13. sidecarcrazy

    sidecarcrazy grandad in gladstone

    Joined:
    Jun 12, 2006
    Oddometer:
    186
    Location:
    Aussie Land
    Thank you, will pm you, thanks to all replies, much appreciated
    PJ
    #13
  14. Melrone

    Melrone Been here awhile

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    Sep 5, 2009
    Oddometer:
    979
    Location:
    Cheese Head Country
    :freakyGood luck,will be interesting to see it build.Too bad your're so far away because I have a Unit Leading Link front end for sale..Its fits a K1100 or any other older K- bike.. Good Luck :freaky
    #14
  15. LasseNC

    LasseNC XSessive!

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    1,083
    Location:
    Denmark, Danimarka, Danmark, Dänemark
    Would you feel that a 35mm OD with 5mm wallthickness tube would be suited for downtubes for my MZ rig? It's a lightweight rig and the bike only produces 21hp.

    *NOT MY BIKE*

    [​IMG]
    #15