Blog

6″ is more than enough

26" custom frame, bicycle, brazed, custom built bicycle frame, custom built hard tail street frame, custom mtb bicycle frame, custom tips, downhill bike, hand built bicycle frame, hand built custom bicyles, machinery, primate frame, single speed, tig bike frame set up, Welded, workshop4 comments

20130209-075107.jpg

20130209-075127.jpg

20130209-075202.jpg

20130209-075226.jpg

20130209-075305.jpg

20130209-075322.jpg

Well it has been a couple of years since I first came up with the idea of building a short travel bike . lots of time spent on auto cad working out angles geo and clearances, originally I had planed to get some plates CNC cut and have the swing arm as a bolt together unit but as happens I kept putting other (paid jobs) ahead of this build . I have been working on a new suspension frame design with a good mate who is a gun when it comes to suspension design so I figured now was a good time to revisit my half finished frame re working the swing arm design to be more in tune with the style of frames I am planing to build in the future. To this end I learnt a lot and I’m very happy with the end result, I’m looking forward to seeing how she performs on the trail.

Stay up right ;)

20130209-083903.jpg

4 Comments
  1. Daniel says:

    Hey Tarn, can you describe your bottom bracket pivot a little? is there a bushing in the frame? is that an inner shell acting as the axle and removable?

  2. Primate says:

    Hi Daniel
    This design uses press fit cups (same as the American Bmx bb size ) there are 2 in the main frame and 2 in the swing arm with spacers to keep everything where it should be.

  3. Justin says:

    Hi Tarn.
    I just came across your site and noticed this 6″ suspension build.
    The idea of having it pivot around the bottom bracket is something I have been tossing around in my head for a while.
    Does this mean that the chain length stays the same as the suspension works?
    If so that means you could use a belt drive with internal geared hub.
    That would be a cool bike no chain banging away or derailleur getting in the way.
    Cheers,
    Justin

    • Wrench Monkey says:

      Hi Justin
      You are correct about there being no chain growth in the sys so a belt would be feasible but having worked with the belt drives in other bikes I would be concerned about the belt alignment as it is very critical to keep the sprocket and chain ring aligned to avoid the belt coming of and the inherent nature of an off road duel suspension bike would make this very hard to achieve but it cold be done .

Leave a Reply