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  1. #1
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    Blur-son (help w the math)

    Kicking around a bit of a project and would like some help w/ the math.
    I have a blt2 with a float 36 set at 150 running spesh purgatory 2.4s. I have had the fork at 140, 150 and 160 and greatly prefer the handling at 150. I also did not like the pedal strikes i got at 140.

    I am thinking of trying to convert it to 27.5 and would like to maintain the 67degree hta and bb height. My thought was that I can drop the fork to 140 , run 2.25 tires with light bicycle carbon rims (shedding weight and gaining stiffness) and run a set of burgtec offset bearings to slacken the hta and lower the bb height. Can anyone do the math on the above changes and let me know if i have overlooked/underestimated anything?

    Thanks!

  2. #2
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    My only thought would be to find someone who has a set of 650 wheels and try them out first before you make the plunge. Even if you don't get the stiffness or the exact feel of your final rig, you learn a lot about the geometry without having to shell out the big bucks.
    Austin Mountain Biking and worldwide travel pictures:

    http://www.austinbike.com

  3. #3
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    I'm not going to do the math for you, but I'll tell you this- there's no way you're going to keep the BB height the same if you go to 650B wheels/tires, even with a "smaller" (but not necessarily shorter) tire and the offset bearings.

    FWIW, I have my Blur LT set up as 650B and I wouldn't have it any other way. The BB height is a little taller, but I prefer it due to the rocky trails I ride here in CO. I run a Fox 32 150mm up front.

    Why not just build it with 650B wheels and ride it before assuming you want it set up a certain way? You may find that you don't need the offset bearings and smaller tires.


  4. #4
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    Good suggestions all.

  5. #5
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    Re: Blur-son (help w the math)

    With the offset bushings and 650b you may have to reduce your travel so you dont bottom out on the seat tube.

  6. #6
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    I may be okay because the rear shock is a pushed RP 23 with a bottom out bumper installed during the factory tune process. Even hitting 6+ foot drops I've never completely popped the ring off the shaft since having tuned.

  7. #7
    NedwannaB
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    I think you're heading in the right direction with proposed setup. I agree with the suggestion to try out some wheels first to get a feel. Maybe even before you do the mods just drop the fork travel as you will be able to put it thru a general test run without too much worry of bottom out issues. You should still be able to run a 2.4 up front, you may also find that a decent 2.25 like an Ardent or Nobby Nic in back works for you too.
    Wait,who did he tell you that?....

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