Putting air in front forks

Discussion in '1st & 2nd Generation 1983-1989' started by slowbird, Jun 22, 2009.

  1. slowbird

    slowbird Member

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    I checked the air pressure in my front forks and I got ZERO PSI in there.

    What is the process of putting air in there? Bike Pump/Air compressor?

    .....and the max is 6PSI no?
     
  2. gunnarf06

    gunnarf06 New Member

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    Do not use Air compressor

    Hey

    I am not sure how much it is I think around 6-8 psi and use a pump NOT A COMPRESSOR.Just a hand pump

    Best regards

    Gunnar
     
  3. midias

    midias New Member

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    Most people don't bother with air but if you want to play around with them only use a hand pump. The general consensus is air can cause premature fork leaking.
     
  4. slowbird

    slowbird Member

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    Soooooo having air in the Forks won't make the bike handle any better? (i.e. less nose diving)

    .....and having ANY air in forks can cause them to leak eh?
     
  5. deepdish

    deepdish Banned

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    yes it will make it handle great :thumbsup:. go ahead and put in about 22psi in each makes it harder but not as much rebound..sometimes you could go as high as 32 but i wouldn't without new seals and thin fork oil sooooo hope that helps you and ehhh tell us how it works. really if they did not use air why would that be there..:rolleyes:
     
  6. gunnarf06

    gunnarf06 New Member

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    Hey

    What the fuck.32 psi he is talking about the front forks 0-6psi(I checked) not the rear shock.Remember to lift the wheel from the ground before you inflate.

    Best regards

    Gunnar
     
  7. JamieDaugherty

    JamieDaugherty New Member

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    NO NO NO. It's best to run NO air at all. Air in the forks just makes them more harsh. Bleed any air out of there and forget that it has the fitting and you'll be just fine.
     
  8. slowbird

    slowbird Member

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    Hmmmm....well if JD says so than I will go with ZERO air.

    I'm pretty sure there is no air in them as it is. Just feels like the front dives alot during moderate braking.
     
  9. JamieDaugherty

    JamieDaugherty New Member

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    That's typical. The best thing to do is install a set of fork springs that are correct for your weight. Believe it or not, the stock spring rate is correct for a zero pound rider. So if you do a lot of ghost riding you are ok, otherwise you need new springs. Once you get that taken care of I'd set the oil level at 225mm and raise it to 200mm if you have any problems with bottoming.
     
  10. Ghost

    Ghost New Member

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    I had every intent on busting Deepdish here and saying "this attempt at humor wasnt funny" However, upon further investigating, I found that factory seals are rated for ~ 54psi. you can also buy upgraded seals which are rated for nearly 200psi.

    Yet still what I did find, was once you apply ~ 15 to 25cc oil, (depending on your bike) if the spring and shock compresses 6 inches, and you have a 170 to 185lb rider on the bike, you would apply ~ 38psi to the system. So the practice of putting in ~ 10psi is within spec of factory seals.

    I would not advise, putting 30psi in them, at the extended (free) state, unless you get your jolly's from replacing seals after every ride.
     
  11. midias

    midias New Member

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    I would think using a heaver weight fork oil would help.
     
  12. JamieDaugherty

    JamieDaugherty New Member

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    That might be true, but for longevity I would not try pushing the limits of the seals.

    Seals aside, adding air to the forks makes them perform worse. In stock form the VF forks are already just this side of terrible, so they don't need any help. Running the correct spring rates, oil, and oil level is the best (and only, really) way to setup the forks.
     
  13. Yonan

    Yonan New Member

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    I would go with Jamie on this one. New springs, gold valves and correct spacers and my 86 eats up any big dips, holes or drop offs great. Dives enough to load the front tire to grip but never bottoms out.

    My manual says to run atmospheric pressure in the forks, or up to six or eight pounds. But its a pain getting the same level in both forks the valves empty so quick.
     
  14. deepdish

    deepdish Banned

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    seems like I knew what I was talking about huh??:rolleyes: oh well do what you want I don't care he asks for aadvice and people condem me for it..now then on a dirt bike you blead out the air but back then the had an air chamber ...on street bikes along with a sail ..:rolleyes::rolleyes::rolleyes:
     
  15. deepdish

    deepdish Banned

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    and you lift the wheel off ground when you (inflate):rolleyes:(like its a ballon):rolleyes:why??? to only put it back down with pressure back on the forks... Well once again the lawnmower techs have spoken.........:crazy::rolleyes:
     
  16. gunnarf06

    gunnarf06 New Member

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    Because

    Hey

    When you would pump a maybe inflatedbal bed you would lie on it while you were pumping:crazy:.Just trying to make the job easier and also if there is pressure one the wheel while you pump is there just more chance that something will start to leak.

    Best regards

    Gunnar
     
  17. Ghost

    Ghost New Member

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    mmmm? no. you are NOT right.

    I will attempt to clarify my comment.

    If a 185lb person sits on the bike, and you put ~ 8 to 10 psi in the fork, you are ok, but at the high end of the spec, and run the risk of blowing the seal... all for a measely 10 psi. Its not worth the headache.

    Suggesting to put 32 psi in a first or second gen std seal is the dumbest suggestion I have read in months, next to a 24" windshield on a street VFR.

    I did some research, and I did find SPECIAL, expensive, RACING seals, which require special oil and a special spring, that will go up to 200 psi.... but using my super elite skills of deductive reasoning, Mr. Watson, I would conclude that slobird doesnt have the 200 psi seals, and thus, the comment from Jamie
    is the most appropriate one.
     
  18. JamieDaugherty

    JamieDaugherty New Member

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    So, how much air pressure are you running in your forks? Maybe you can help the Lawnmower Techs out with a real world example.
     
    HellFishTat likes this.
  19. gunnarf06

    gunnarf06 New Member

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    .....That is so right,Jamie

    Gunnar
     
  20. Tilts75

    Tilts75 New Member

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    Interesting thread, just posted a similar question. So what was the final outcome, did you increase the air pressure, or change springs, just checked mine, and had no air at all in both forks, im going to try 15 PSI, and see if that stops the bottoming out, end of the day the bike SHOULD be able to tolerate minor pothole's and hardbraking without bottoming out, with the need to change factory springs, surely.:frown:
     
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