BMW R90/gs build

Discussion in 'Old's Cool' started by djkilmer, Jan 4, 2011.

  1. djkilmer

    djkilmer Adventurer

    Joined:
    May 27, 2008
    Oddometer:
    16
    Okay folks just sold my Cagiva Gran Canyon to focus $$$$ on my R75/6 soon to be enduro. I currently have to bike disassembled. I have sourced all the body parts which are a mix of Acerbis/UFO/Baja Designs. The bike is now sporting a /5 police tank from Germany. The bike is going to become a R90 with the R90S pistons and freshly bored jugs, she fill guzzle her fuel through the mikuni flat slides I have.

    Question 1. I am trying to figure out what front end to roll with, inverted or standard? Is there one pair that is easier to adapt? I want to use a complete front end, triple/forks/wheel. I understand perhaps some machining will be involved, just mainly curious about fork options, IE: XR600, Xr650L, CR450R, YZ250F? Is one inverted better than the other because of the different taper lengths where the triples ride?

    Question 2. Rear swingarm. I want to use the dual shock swingarm but lengthened to match forks. I have a post 81 swingarm for better rigidity. What is a good length? 3-4 inches? I am trying to figure out a jig to secure the arm for cutting/welding but cannot seem to come up with a good plan to hold the rear of swingarm. Does anyone on here offer a service to lengthen a dual shock swingarm? Or have a picture of a jig? I can find one but its not to clear on the rear.

    Thanks!

    Attached Files:

    #1
  2. fishkens

    fishkens Long timer

    Joined:
    Nov 14, 2009
    Oddometer:
    5,252
    Location:
    Seattle, WA
    I've seen 100 and 120 mm extensions. Or something like that.

    Recommend using google to search this site for many earlier threads (albeit fewer on dual sided swingarms).

    e.g. google: airhead dual swingarm length site:advrider.com

    http://www.advrider.com/forums/showthread.php?t=468420

    Are you in WA?
    #2
  3. BROTOWNBOY

    BROTOWNBOY Been here awhile

    Joined:
    Oct 5, 2007
    Oddometer:
    293
    Location:
    nth wst nsw
    checkout post no 60 http://www.advrider.com/forums/showthread.php?t=516530
    #3
  4. djkilmer

    djkilmer Adventurer

    Joined:
    May 27, 2008
    Oddometer:
    16
    yup up here in Bellingham,
    I am convincing myself to use a front end off a XR650L, any one used that specific fork?
    #4