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  1. #1
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    Lefty pbr 140 conversion - air spacers

    Hey,

    I just finished my conversion and was wondering if anyone could tell me exactly what effect using bigger or smaller air spacers has. does using larger spacers increase or decrase suppleness?

    also how important is it to trim the air seal in the solo air down to 49mm?

    lastly, and this ones propably dumb, but does anyone else have trouble with losing air pressure when you remove your shock pump? is there a better pump out there or am i just missing something?

    Thanks for the help,

  2. #2
    LA CHÈVRE
    Reputation: Dan Gerous's Avatar
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    I'll let someone who knows more about conversions answer the first two points but for the last, in normal conditions, the air you hear escaping as you disconnect the pump, is the air that was in the pump, not the Lefty (or any air fork or shock). When the pump is connected and opens the valve, you pump so the air inside the fork and the pump is pressurized, when you disconnect it, the valve normally closes first then the rubber seal between the pump head and the valve opens so when air comes out, the valve is already shut and the pressurized air in the pump releases. That means you didn't lose any air in the Lefty. But if you connect back the pump to check pressure, that's when you actually lose air from the Lefty as once the valve opens, air from the shock goes into the pump so the pressure of the new, bigger air volume is now lower... Makes sense?

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  3. #3
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    Thanks...Yea, I knew that was the case it just seemed like when i reattach the pump the pressure was down more than normal so i figured i must be losing when i detach as well. Thanks again!

  4. #4
    LA CHÈVRE
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    The amount by which it drops depends a lot on the volume of the Lefty/shock. Smaller volume, bigger air loss. Also the volume of the pump, if it takes more air to fill it up, it will 'steal' more air from the Lefty...

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  5. #5
    Mr. Knowitall
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    There are pumps with check valves close to the outlet of the pump.

  6. #6
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    Quote Originally Posted by hssp
    There are pumps with check valves close to the outlet of the pump.
    How do you know your pump has a check valve?
    Lead by my Lefty............... right down the trail, no brakes.

  7. #7
    LA CHÈVRE
    Reputation: Dan Gerous's Avatar
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    You also have to wonder how much reliable are all these cheap pumps gauge anyway. That's why I always suggest starting with suggested pressures if you want but then adjust by sag and feel/preference... And if with your pump, you know that you need to pump 110psi, whether it's true or not, even if you think you add 5-10psi to compensate for the air loss you think occurs, to have it feel and perform great, whatever you do, if it feels good, just do the same and the result should be consistant...

    DAN.GEROUS.NET : MOUNTAIN BIKING : CYCLOCROSS : ROAD :

  8. #8
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    Mine loses too much air removing my roxshox pump too, like 30 psi between putting it off and back on.
    I was actually googling a solution and found this thread.
    I have a 2010 140 pbr

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