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  1. #1
    In my mind, I can do it!
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    Under pressure....

    So those of you with 575's, do you set up your shock according to sag or some value under your total weight? I downloaded the 575 owner's manual and it states 20% to 30% sag. Personally I would rather use the weight method because it seems easier to figure out than eyeballing 20 to 30% sag.

    I am probably 185lbs with the camelbak on. No tools or waterbottles on the bike.

  2. #2
    Bad Case of the Mondays
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    I set mine up based on sag (25%), with the propedal lever in the middle setting. I also put my camelbak with water in it on when I'm setting up suspension, as my Hawg can be close to 20lbs on big ride days with water, food, tools, etc.

    Suspension is very personal, as is the ultimate way to get it right for you so just do whatever method works for you. I'm very anal about having things dialed in just perfectly so that is why I use the above process.

  3. #3
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    why eyeballing? Put an o-ring on the shaft, sit, get off the bike, measure sag and adjust pressure ?
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  4. #4
    In my mind, I can do it!
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    Quote Originally Posted by Jdub
    I set mine up based on sag (25%), with the propedal lever in the middle setting. I also put my camelbak with water in it on when I'm setting up suspension, as my Hawg can be close to 20lbs on big ride days with water, food, tools, etc.

    Suspension is very personal, as is the ultimate way to get it right for you so just do whatever method works for you. I'm very anal about having things dialed in just perfectly so that is why I use the above process.
    Do you check the pressures before each ride as well?

  5. #5
    Hi!!!
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    Quote Originally Posted by iviguy
    Do you check the pressures before each ride as well?
    I check every couple of weeks.

    I set mine according to my weight. As of last week I had 230 in the RP3 and I'm over 200+ loaded down.
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  6. #6
    Bad Case of the Mondays
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    Quote Originally Posted by iviguy
    Do you check the pressures before each ride as well?
    No, maybe once a month or so. If the suspension isn't acting the way I expect it to, then I check it but I don't notice much leaking in a month's time.

  7. #7
    In my mind, I can do it!
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    Quote Originally Posted by goRz
    why eyeballing? Put an o-ring on the shaft, sit, get off the bike, measure sag and adjust pressure ?
    Maybe I should restate. First you have to know where full travel is on that shock, maybe it's 2", I don't really know. Then set the o-ring, sit carefully so not to bounce, get off carefully and measure. Figure the percentage, if it's not right pump and try again.

    If you set to a certain weight figure like 210psi then you take all that other stuff out of the equation.

    That said, why couldn't one check the sag and see what pressure is perfect and just continue to use that? Given that your weight is pretty consistant that is.

  8. #8
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    Quote Originally Posted by goRz
    why eyeballing? Put an o-ring on the shaft, sit, get off the bike, measure sag and adjust pressure ?
    What he said.

    Pressures are pretty critical. If you're +5 lbs. above the optimum, the bike's ride will be firm, if you're -5 lbs., it will be soft.

    I've found no reason to check more than occasionally and you should know that every time you attach the pump, your pressure will drop about 15 psi, so you'll have to set the pressure every time you check.
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  9. #9
    Bad Case of the Mondays
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    Quote Originally Posted by iviguy
    Maybe I should restate. First you have to know where full travel is on that shock, maybe it's 2", I don't really know. Then set the o-ring, sit carefully so not to bounce, get off carefully and measure. Figure the percentage, if it's not right pump and try again.

    If you set to a certain weight figure like 210psi then you take all that other stuff out of the equation.

    That said, why couldn't one check the sag and see what pressure is perfect and just continue to use that? Given that your weight is pretty consistant that is.
    You are making it harder than it really is. Download the shock setup manual from Yeti's website, and then all you have to do is measure from the oring to the end of the air chamber.

    And you can get the sag/feel right and then just ensure it stays at that setting, that is basically what I do to just a different method of obtaining that magical psi number. Also remember that different pumps will give different readings, so you need to find out what psi number on your pump gives you the right sag and suspension feel.
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  10. #10
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    Quote Originally Posted by mbmojo
    What he said.

    Pressures are pretty critical. If you're +5 lbs. above the optimum, the bike's ride will be firm, if you're -5 lbs., it will be soft.

    I've found no reason to check more than occasionally and you should know that every time you attach the pump, your pressure will drop about 15 psi, so you'll have to set the pressure every time you check.
    my experience with air shock was Swinger 3way on Reign and I also checked pressure every few weeks. Pressure drop also depends on the type of pump.
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  11. #11
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    My advice: Set up your bike using the oring to check sag. Set it at 15,20 and 25 or 30%. Make a note of the psi you needed to obtain each. (You will want more or less sag depending on the type of riding. In Dallas I'd imagine you would want a firmer, more responsive ride since there aren't any mountains, around 15 or 20% sag, but that's a personal preference.) Ride at different settings to get a feel of what you like best. + or - 5psi or so on the rp3 can make a really big difference on the ride of the 575. Once you find out what kind of sag you feel best with then just pump up to that psi when needed.

    Its good to know the sag measurement on the bike so you can ensure you have enough to soak up the ruts and potholes (more like extend into...) too little sag is no good.

    I made my point waaay too long winded......its really a simple process. For fast, rolling xc rides you want 15 or 20% sag to keep things firm. For stairstep, technical, rocky days or drop offs you will want more like 30%.

    BTW the shock stroke is 2'' like you said so.....25% sag =.......1/2 inch

  12. #12
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    I set mine to my weight (naked). In the last two years I have fluctuated from 205 to 175 and everywhere in between (185 now). Setting the PSI to my weight has always worked very well.

    BTW - My clothes and gear (camelbak included) weigh ~15lbs.

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  13. #13
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    setting shock at altitude?

    I use the o-ring/owners manual method. My additional question is when adjusting or setting up the shock at altitude (7500 ft+) are there any considerations to be made for the lower atmospheric pressure? I normally ride at 5500 so i doubt there is much difference.

    I did notice fiddling with the RP3 at the top of my last ride that I was pumping the hell outta the shock pump to raise the needle 10-15lbs. And if my pump bleeds 10lbs just connecting it maybe I won't mess with my settings till i get home. Any more info on where that *psssst* of air comes from after unscrewing the shock pump?

  14. #14
    In my mind, I can do it!
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    Quote Originally Posted by tahoe_County
    Any more info on where that *psssst* of air comes from after unscrewing the shock pump?
    It comes from the hose. When you reattach it though the hose fills with air from the shock which takes about 10 to 15psi with it. If you connect, disconnect and reconnect you will see the drop in pressure on the shock. However, if you connect, pump to the pressure desired and then disconnect it will be what you left it at.

  15. #15
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    Set it (and forget it) at 44 lbs. It works well

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  16. #16
    Young, Shawn Young
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    Set it to your body weight before you put your camelbak on. If you set it with all your gear on your ride will prolly be a little more harsh than you want. Thats just my unscientific method
    "Im just going to explore a little bit..."

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  17. #17
    HowtoOverthrowtheSystem
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    Screw all this typing stuff...

    Go find a nice technical piece of trail to ride over and over. Take your shock pump along and mess with the pressure, rebound and Pro-Pedal settings until it feels like buttah.

  18. #18
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    setting sag on 575/RP-3

    I found that I set a lower pressure than recommended to get 25% sag. Also, with 1/2 inch sag at minimum propedal, I have 1/4 inch sag at max propedal. I bike within a range of 7000' to 10,000 feet almost exclusively and find that 145 psi gives me 1/2 inch of sag as opposed to the recommended 170 psi. That may just be how my RP-3 behaves. I weigh 160 with all of my stuff.

  19. #19
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    tell me how is the riding altitude supposed to affect air-shock performance?? it;s a closed cylinder so the pressure inside does not change with altitude.and when you're pressurising shock, lower atm. pressure at greater altitude means only that you will have to pump longer to reach desired pressure inside (I doubt whether its noticable in practice ). Unless we assume that the greater the altitude the smaller the gravity force as we're further from center of the Earth
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  20. #20
    EDR
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    Quote Originally Posted by goRz
    tell me how is the riding altitude supposed to affect air-shock performance?? it;s a closed cylinder so the pressure inside does not change with altitude.and when you're pressurising shock, lower atm. pressure at greater altitude means only that you will have to pump longer to reach desired pressure inside (I doubt whether its noticable in practice ). Unless we assume that the greater the altitude the smaller the gravity force as we're further from center of the Earth

    How is it that a bag of potato chips expands to near explosion when taken from 1k ft to 10k feet? It too is in a closed enviroment.

    Pressure is relative. The expanding air in a shock cyclinder (when gaining altitude) just doesn't impose such a great force that it can deform the shock casing and thus be obvious to us. If the shock casing were made of potato chip bags it would. Or, maybe I'm just bored...

  21. #21
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    Quote Originally Posted by eatdrinkride
    How is it that a bag of potato chips expands to near explosion when taken from 1k ft to 10k feet? It too is in a closed enviroment.

    Pressure is relative. The expanding air in a shock cyclinder (when gaining altitude) just doesn't impose such a great force that it can deform the shock casing and thus be obvious to us. If the shock casing were made of potato chip bags it would. Or, maybe I'm just bored...
    .. that was funny...... air in the shock cylinder is NOT expanding because casing is 'not made of potato chip bag' same as in the case of submarine, air inside is NOT compressing due to hard shell of the ship.... god! a bit of physics....
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  22. #22
    EDR
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    Quote Originally Posted by goRz
    .. that was funny...... air in the shock cylinder is NOT expanding because casing is 'not made of potato chip bag' same as in the case of submarine, air inside is NOT compressing due to hard shell of the ship.... god! a bit of physics....
    Just answer this: Why does the bag expand? Because the pressure inside increases relative to the outside or the bag is weak? Answer: Both. Without increased relative pressure there is no force to expand the bag, if the bag were made of steel it would not budge. Remember, I'm talking about pressure that is RELATIVE to the surrounding enviroment.

    We've done this before I think and that was enough then....I'm no teacher, I just play one on TV!

  23. #23
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    Quote Originally Posted by eatdrinkride
    Just answer this: Why does the bag expand? Because the pressure inside increases relative to the outside or the bag is weak? Answer: Both. Without increased relative pressure there is no force to expand the bag, if the bag were made of steel it would not budge.
    yeah, but in post , which started this ridiculous discussion I talked about a SHOCK not a bag. so shock is tough, and firmly closed, and thus pressure inside does not change depending on altitude and that's it!

    I think we went too far OT, let's drop it here...
    Last edited by goRz; 06-07-2006 at 10:24 AM.
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  24. #24
    In my mind, I can do it!
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    Quote Originally Posted by eatdrinkride
    Just answer this: Why does the bag expand? Because the pressure inside increases relative to the outside or the bag is weak? Answer: Both. Without increased relative pressure there is no force to expand the bag, if the bag were made of steel it would not budge. Remember, I'm talking about pressure that is RELATIVE to the surrounding enviroment.

    We've done this before I think and that was enough then....I'm no teacher, I just play one on TV!
    I'm going to have to agree here. I know from back when I was into Scuba diving that when they fill the tanks the pressure that they put in the tank would vary according to the altitude where it was being filled. So someone filling a tank at sea level would not fill the tank to the same pressure as someone filling it at 10,000 feet. This is done on purpose because the tanks are rated at a certain psi.

    Another example here is when diving deep and doing an ascent. You absolutely have to exhale while ascending because if you don't your lungs could explode. If you hold your breath at the surface and dive as a snorkeler would do you can go as deep as you want and continue holding all the way back to the surface. If you are breathing the air from a tank at 100' and do a quick ascent while holding your breath and not exhaling, you are going to be one hurting dude. There was a girl in NM who freaked at about 90' and pulled the emergency cord on her BCD which quickly aired it up and shot her to the surface. She held her breath and didn't exhale what was in her lungs and died.

    As far as subs go, they equalize the pressure in the sub as they descend and the hulls of a sub are designed to compress. They do compress.

  25. #25
    Hi!!!
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    Quote Originally Posted by Redmon
    Set it to your body weight before you put your camelbak on. If you set it with all your gear on your ride will prolly be a little more harsh than you want. Thats just my unscientific method
    I'm actually gonna try this method. I think I have 230 in right now and it does ride a bit harsh. But then again our trails here are pretty much nice and smooth and involve a fair amount of climbing so I want my suspension firm for the ride.
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