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I-Track Suspension Prototype Unveiled

Discussion in 'Downhill & Freeride' started by hmcleay, Jan 21, 2013.

  1. hmcleay

    hmcleay i-track suspension

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    Hi all,

    Since this is the very forum that inspired me to develop this design, I thought I'd share it here first.
    It's incredibly satisfying to have built and ridden something which up until yesterday was all based on theory. I'm very proud to show off this prototype, and I'm excited about the future possibilities that this design is capable of.



    Please visit www.i-tracksuspension.com for a detailed description of this prototype.

    Thanks for reading.

    Cheers,
    Hugh.
     

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  2. blackohio

    blackohio Generous jaywalker

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    wow, that things got some serious rearward path.
     
  3. TrueScotsman

    TrueScotsman Monkey

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    Incredibly Cool!

    I have been following this build for a while now on FB and I have to say major props for getting it built! (and doing all the calculations behind it)

    Great to see alternative thinking- yes it is a very high pivot but it is all done for a reason. The only reason we are used to seeing the "traditional" low pivot is due to chainline forces. Once you separate out the chain forces it opens up all manner of options.

    Also nice that this is all being done out in the open for us all to follow and read up on.

    All in response to this thread on Anti-Squat and Idlers here on RM! (and a lot of brainpower by hmcleay!)

    Good work!
     
  4. blackohio

    blackohio Generous jaywalker

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    I wasnt knocking rearward path, just commenting on it. We all know how well JEdi's and Zerodes eat up the rough
     
  5. ak pura vida

    ak pura vida Chimp

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    so how much rearward travel does it have?

    pv
     
  6. jonKranked

    jonKranked Press Button, Receive Stupid

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    mmmmm steel
     
  7. 0110-M-P

    0110-M-P Monkey

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    Based on the 203mm "Vertical Wheel Travel" and 230mm of "Total Axle Displacement" it looks like it would be ~108mm (4.25") of horizontal (rearward) wheel travel.

    That is, unless "total wheel displacement" means the distance traveled through the arc and not diagonal straight-line axle displacement.
     
    #7 -   Jan 22, 2013
    Last edited: Jan 22, 2013
  8. rosenamedpoop

    rosenamedpoop Turbo Monkey

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    Looks great Hugh, care to share your impressions from your test ride(s)?
     
  9. Sandwich

    Sandwich Pig my fish!
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    How did it corner with a pivot that high?
     
  10. hmcleay

    hmcleay i-track suspension

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    Yep, that's correct. 108mm of rearward travel.

    I've only done a few easy runs on it so far, so it's very early days.
    But, my first impression is that it pedals pretty well, better than my Scott Voltage FR, although could probably benefit from a bit more anti-squat. But that is often a matter of personal taste.
    Conveniently, I can tune the AS by altering the length of that small link visible on the RHS of the bike.
    It feels incredibly planted/stable/controlled through the rough stuff, especially off the brakes (duh!). I found myself plowing through sections off the brakes that I would never have done on my other bike.
    I'm still getting used to the slacker HA, so I think that is limiting my cornering at the moment, but I can't say I noticed any flaws (due to the rearward axle path) when cornering.
    Manualling is definitely more of an effort though.
    I haven't even begun to play with spring rates and shock settings, so it's still very early days!

    I'll try and get a heap more testing done this weekend.
    I'm pretty sure that my riding ability will be a limiting factor, so might try and get some faster guys on it so see what they can do.

    Cheers,
    Hugh