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  1. #1
    mtbr member
    Reputation: drewactual's Avatar
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    air suspension question for big guys

    I just loaded a swinger on the back of my Heckler......I loved the Cloud Nine I still have, but wanted to ride w/ a 2.25" piston and see if i was actually missing the travel the CC @ 2" was missing....jury still out.....but anyway, at the same time I loaded up the fork (Minute Super..SPV@ 175psi, main chamber 205psi) which is quite a bit firmer than usual....duh.....I figured if I was going to tote a shock pump to explore different settings w/ the rear, I might as well re-explore the fork...

    Anyway, I noticed something during all of this, and was wondering if I could learn from somebody else who has already done this:

    The travel was a lot more firm both front and rear, which was good to a degree- on big hits I didn't bottom out or even 'squish' to the point it was noticable (sucking momentum)- but during 'chatter' sections I noticed I was bouncing all over the place, it felt sorta like riding did before I went to a thru-axel......somewhat loss of control and feeling like the bike was choosing the line.....

    where and how do you find a happy medium? I weigh in @ 270-280 dependig on gear carried + h2o, and I am starting to believe it a curse of weight that the fine line between using full progressive travel for big hits, and smoothing out the chatter + maintaining control on succsesive small hits impossible for us big-uns......thoughts? btw, I have played with every rebound setting these shocks have (well, a lot anyway), as well as SPV chamber volume.... it seems there is no way to find a compromise....shoot, I even played with pressure in the blasted tires to see if that could play into it too!

    I am interested to see what other heavy riders have figured out on their own.....and not just with platform shocks and forks, but with any air suspension setups.....and most of all if being as heavy as we are, if it is possible at all....

  2. #2
    Are you gonna eat that?
    Reputation: Kyoseki's Avatar
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    Air shocks are a bit of a compromise from what I've seen, you don't get the true adjustability of a coil shock (preload, spring rate, high/low speed compression & rebound).

    With a single compression damping knob (never seen fast/slow compression control on air shocks) you'll always be trying to find a compromise between the big hit ("slow" compression) and washboards ("fast" compression).

    I wouldn't worry too much about rebound damping, but it's nearly always a compromise too. Rebound damping is usually just set based on spring rate (air pressure) and unless your shock can decouple fast and slow compression you certainly won't be able to decouple fast and slow rebound (the only bike shock I know of that does this is the Cane Creek Double Barrel and I wasn't even aware fast/slow rebound damping was available at all on anything until about half an hour ago ).
    Due to a lack of interest, tomorrow has been canceled

  3. #3
    Chillin the Most
    Reputation: RED5's Avatar
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    I'm about 260 geared, full 100oz Camelbak and gear. Currenly,I've got an 06 Kona Dawg with a DHX-A with the RP3 sleeve on it and it's not complete crap. However, I've heard awesome things about the Roco Air, so I ordered one and I'm gonna give'er a go over the next week, while I'm on vacation in the Auburn/Tahoe Ca area. I'll give a report back when I've had some time on it.

    In the mean time do a search for Roco Air and read up, it sound very promising for bigger guys. Some of the riders have been able to drop pressure from 175psi on RP3's for a 180lbs rider to 120psi on the Roco (or something close to thereabouts).

  4. #4
    Double-metric mtb man
    Reputation: Psycho Mike's Avatar
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    It also depends on the leverage ratio. My Cake runs a low ratio, so I can get away with 110 psi in the main spring of my Swinger 3way. I actually think I've found the sweet spot as I absolutely flew home on the trails on Monday and it was doing well for both the washboard and the bigger stuff.
    As if four times wasn't enough-> Psycho Mike's 2013 Ride to Conquer Cancer Page

    Moran? Let your opinion be free -> F88me

  5. #5
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    Sounds like too much platform

    Or too much in the main chamber or both. I ride a Blur LT with an RP3 on the back that I run in the middle platform position and body weight air pressure or slightly less. I run the recommended air pressure in my Pushed Talas fork. This gives about 20%-25% sag on both ends and works great.

    Stable platform rides a little harsher than a free flowing suspension on the small stuff. Until you overcome the platform you are essentially riding on a locked out suspension. Too much platform will cause your wheels to bounce around like crazy on small chatter bumps. Its just like going back to a fully rigid bike. Too little air in the main chamber will cause bottoming. If you can adjust each sperately, I would suggest that you start by reducing the pressure in the SPV chamber a little at a time until the supension starts to soak up some of the chatter. Once that is working better you can try reducing main chamber pressure a little if you feel that you don't have proper sag. When things are woking correclty you should be able to ride most reasonable bumps on the trail without pogoing off or bottoming out.

    Excessive rebound damping will cause you suspension to pack out over chatter. Essentially the suspension has not had time to extend after soaking up one bump before the next one gets soaked up. This could also cause the problems you are having on small bumps. Rebound needs to be set so that the suspension extends between hits but doesn't give you the pogo stick feeling.

  6. #6
    mtbr member
    Reputation: drewactual's Avatar
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    I will revisit the SPV thing......there is no doubt I have it set up incorrectly....foul thing is the fork was all but perfect before I started screwing with it..... I used the same settings I had on a '05 minute :03 and it was good enough anyway.... even through/after the break-in period I never changed it....maybe I just got used to it was what I was thinking when I changed it, and that there was actually more performance to squeeze out of it....should not have second guessed myself I guess... :-)
    ...(by all but perfect I mean the comprimise was a little on both big and small hits- neither perfect, but both well enough)

    The rear shock is quite different though from the cloud nine......which by the way has both rebound and compression and partial lock-out which I never used ..... I kinda like the real solid feel of the swinger, but will have to play w/ the spv pressure and main chamber quite a bit I fear....with the CC I only had to make minor adjustments from where I started in the begining (which was 245psi)..... btw, the swinger is a three way so I can't adjust SPV volume with it....

    I will explore though, keep the advice coming- it is very helpful!

  7. #7
    Chillin the Most
    Reputation: RED5's Avatar
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    Update:
    Got the ROCO locked and loaded on the Dawg last night. Did the initial setup, set sag & adjust rebound. One very cool thing...the ROCO only needed 200psi to get the 25% sag whereas the DHX-A w/RP# sleeve needed 270-280 (depending on what gear I carried). Me likey so far, but the real test will come over the next week while I ride the piss out of the ROCO. Will post back with more later.

  8. #8
    anyone else smell that?
    Reputation: jgsatl's Avatar
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    i run a roco at about 175 psi on a 2.78 to 1 leverage bike (mtn. cycle zen) and it seems very plush. i'm 235 nekkid.

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