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  1. #1
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    Bottoming my Flux?

    Hey all - newbie dual-squishy owner, I finally got my bike to the trails today. I managed to bottom the rear end out twice on a couple of relatively small jumps at speed, and one small low speed drop of about 16 - 20 inches that I landed all on the rear end.

    I'm no big-air rider, although I will catch a little air over a few sections of the trails that I'm familiar with. These aren't big gaps, or massive drops, just basic rollers that you boost off the top and carry it a few feet away at speed. It all definitely falls within a normal "XC" type of riding style.

    Here's the setup - I'm 190-ish in my riding gear with a full hydration pack, sidi's and whatnot. The bike has a RP3, and I set the sag initially to the 12mm that Turner's website suggests. I like the feel of full propedal, so I've left it on setting #3. After feeling that it was a touch soft, I added a little more air. This cut the sag down to more like 6mm. I'm running the rebound dampening at about 3 clicks in and it really feels like it follows the trail well.

    I bought this bike used, and the prev owner told me that he weighed about 210 I think. So if anything it should have been valved for a slightly heavier rider than I am. The sticker on the RP3 says it is the medium propedal valving. The bike was initially a 05, but he cracked the front triangle, and got a replacement 07 front end with an RP3, and the rear is the original Horst link. (This is all me going on the story in the eBay ad) Either way the bike showed up, in the condition I was told it would be, I got a good deal, all is well there.

    Long story short - should I be bottoming the rear that easily? I mean I'm pretty sure that the upper link where the rockers bolt on has made contact with the back of the seat-tube. There is a small indentation there, and it looks to be exactly where that would eventually hit. I def. don't want to continue smacking the rear suspension into the seat tube if that's the case.

    Suggestions?

  2. #2
    guy who bikes
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    Hey, I'm 190 lbs. with gear as well, and rocking an eerily similar setup of an '08 Flux with an HL rear from an '01 XCE. Someone else can tell how similar the rear triangles are, but I'm pretty sure they would cycle almost the same. I have an RP23, and have never had a problem bottoming out the shock even on some jumps that exceeded an "XC" classification. I have my shock at 165 lbs. of pressure. This gives me roughly the 12mm of sag and works great. What's your air pressure at? Also even when I was checking the suspension cycle with zero air in the shock, the shock bottomed out before the seatstay could hit the seat tube. Are you sure you have the correct sized shock, because a shorter one would explain all of the problems you have described?
    The world isn't so bad if you can just get out in it...

  3. #3
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    That explains some of it - I only have about 145psi in the shock, but the sag is less than 12mm. I did just go out and take one of the bolts out of the shock, and the suspension does move up to contact the seatpost in the spot that I have the mark on the frame.

    Let me go and try your idea of cycling the suspension without any air. Be back in a bit.

  4. #4
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    Ok- with 0 air, the suspension doesn't cycle enough to touch the frame. At least not under load - it come up about 3/32 short maybe? Perhaps a little less. I sat on the bike and let my weight try to make it move more - but it didn't make contact. I didn't try very hard - probably not good for the shock. But the small mark on the tube definitely is where the suspension touches it if I unbolt the shock.

    I repressurized it back to about 165-170 like you mention. Do you know if your RP23 is the normal volume air can?

  5. #5
    guy who bikes
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    Ok, the clearance is about like mine, very small but still enough to prevent contact. I have no idea what volume air can I have, but as I ordered it directly from Fox for my Flux and the question was never asked, I would assume it's a normal volume can. I can say that it looks to be the same size as what comes standard on the Giant Trance's at the store I work at. I don't know enough about suspension to know if that would explain the difference or not. Is yours a low volume? See how it rides with the higher pressure. If that doesn't work, you might want to X-post this in the suspension forum where someone might be able to offer better advice. Let me know what you discover.
    The world isn't so bad if you can just get out in it...

  6. #6
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    I have an 05 flux with a standard RP3 (I've never seen a large volume RP3 on the flux) and have a similar weight as you. I also do small jumps and rollers at speed but have never had a problem bottoming the shock. I'm not doing anything over 1.5 to 2 feet on this bike though. I just checked the sag and I'm at 9mm (I've lost some weight and probably should reduce pressure to get to 11mm of sag).

    I usually check sag with rebound full fast and compression open (in the "-" position - no propedal). It's possible you're getting a different reading if you're checking it with compression in position 3.

    On a side note, three clicks in from full slow on the rebound doesn't seem like enough. If you're in a really bumpy section it might be possible you are bottoming b/c the rebound is too slow and the shock isn't coming back to give you full travel. My 2 cents...

  7. #7
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    Thanks - I'll check the sag tomorrow with the propedal open, and the rebound dialed all the way fast. My 3-clicks was from full fast, not full slow, I ride pretty rooty rough stuff at times, and don't want it packing up at speed.

  8. #8
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    FYI - the HV air sleeve looks like this - Push sell sthem on thier site:
    http://pushindustries.com/products.p...tle=Components

  9. #9
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    Sounds like it would be worth sending your shock to Push and getting the compression settings dialed to your liking. I weigh 165 with gear and run the shock at 140 with about 12mm of sag. I did the push upgrade and it was was well worthwhile IMHO.

    Are you sure you put that mark in the seat tube? The other way it can be marked is during servicing if the shock is out and the rear suspension is allowed to move freely and hit it. Could the previous owner have done that by mistake?

  10. #10
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    Well, - it is possible it was there before - the frame had been ridden for about 3 months before the prev. owner bought a Spot and sold me the Flux.

    I was basing the contact off of the sound that I'm hearing when the rear end bottoms. From what everyone here is telling me, I was running less air pressure than someone my weight needs. I was running about 145psi, at a 190lb riding weight. Plus I was hearing a sound that sounded metal-on-metal, but the indentation on the tube isn't very significant. Not what I would expect if they were hitting with much force.

    I'm measuring sag the way the fox manual states, sitting in a riding position on the bike , not bouncing, in riding gear, and measuring the distance the o-ring moves. 12mm/.5" give or take. I didn't think to turn the propedal off/full soft, and rebound dampening full fast. I'll check it again tonight with a little more air in the shock. If I still have the problem, I'll probably have to send it off to Push. Might as well send them my Revelation at the same time and get it all pimped at once.

  11. #11
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    I had a similar bottoming problem with an RP3 after I had abused the heck out of it for a couple years. Got a bigger can - didn't help. Sent it to Push. It came back and feels great now - no more bottoming. Push sets it up for your weight and riding style, and it seems to have worked for me.

  12. #12
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    Yeah- I'll probably send it and my Revelation to Push this winter. Ouch - $365 for pro-service on both.

  13. #13
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    Just a follow-up - a couple of rides with about 170 in the shock has taken care of the hard bottoming I was getting. I also lowered Pos. spring presure, and reaised pressure in the Neg spring in my Revelation a bit, and it's feeling way more plush on small input stuff.

  14. #14
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    Seems to me that 12mm is probably a little too much sag on a Flux. That would be about 30% of travel. I try and run mine at about 25% sag (~9mm) and I don't get hard bottoming. You're also better off running the shock a little more firm in order to keep the shock from bottoming hard. If the shock bottoms hard the force then gets transmitted into the frame. This, I believe, is a major cause of the seat tube cracks.

    Oh yeah, +1 on the PUSH mods. Have 'em on the RP3 and the Reba and they rock!

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