Results 1 to 10 of 10
  1. #1
    mtbr member
    Reputation:
    Join Date
    Aug 2009
    Posts
    59

    Does BRAIN miss the first bump??

    I've been reading up about the Brain rear in Specialized Epics. (I've ordered a 2010 Epic Comp 29er).

    Now, I understand that a valve opens up when the bumps on the rear wheel are significant enough to cause it to cross some sort of threshold.

    But I read a few reviews that state it takes a second or two to open up.

    So does that mean the first bump or two the bike is like a HT until the brain opens.

    It doesn't seem to make much sense - the initial bump is often the worst. It's the one that bucks you out of the seat.

    Lets paint this picture - you're riding along on flat, smooth, so Brain is not active/released whatever it's called. There is a log across the trail, only a little one. So all else is smooth except this one bump. As you cross the one bump, does the brain become active BUT not in time that the rear shock absorbs the bump, and by the time the brain is active there are no more bumps?

  2. #2
    mtbr member
    Reputation: SurfSailRide's Avatar
    Join Date
    Dec 2008
    Posts
    919
    (Subscribed)

  3. #3
    mtbr member
    Reputation:
    Join Date
    May 2005
    Posts
    1,379
    No, it reacts very quickly, you will not feel the log at all if the Brain is set correctly. If you have the brain on the firmest setting, you might feel the wheel touch the log, but it will break free before the other side.

    Smaller bumps seem to be the trick in setting the Brain up, as at what point are you comfortable with??? I have mine set on a 29er SJ FSR to activate at about 1cm bumps. Not very effecient, but comfortable for me and my old back

  4. #4
    Craigez
    Reputation: ANTTEI's Avatar
    Join Date
    Jul 2009
    Posts
    22
    If properly set, the purpose of the brain is to react.

    It needs some trigger, needs an obstacle that will wake him up
    So it depends on the obstacles you get in your way...if they are aggressive but very short you will not notice the brain to work, but trust me it really works.

    In the beggining it's strange, it's too mechanical while compared with other FS, but in the end it's really eficient not to have to worry about propedal, etccc

    Then again you can set the brain to react to almost anything, but then it's not a brain anymore it's just a FS bike without any blocking possibility

    Tale Care
    If everything seems under control, you're just not going fast enough.....Mario Andretti

  5. #5
    mtbr member
    Reputation:
    Join Date
    Jan 2008
    Posts
    790
    The AFR Brain and 2010 Fox manufactured Brain are very sensitive and open up very quickly to all bumps, including the initial bump and small bumps. These Brain's have platform firmness adjust, for the AFR its termed flow control. You get to determine how firm/efficient of a platform you enjoy riding with. In a softer setting the shock is allowed to be active on smooth terrain. In the firmest setting the shock will still be fully active opening up for all bumps but will have a hardtail firm platform in smooth terrain. Immediatly after the bump subsides the brain platform returns to its firm setting. The Epic has a race tuned platform it is very firm in the full firm setting, the Stumpjumper has a trail tuned platform and its firmest platform is just shy of the race tuned Epic. The earliest generation Fox produced Brain 2003-2006, an initial bump was needed to activate the Brain and then the Brain remained open for a few seconds after the last bump, the feedback that we got from this early generation allowed us to improve brain function to what it is today. Sensitive to all bump sizes, functional for the first bump and returns to its efficient setting immediatly after the last bump.
    Visit my profile for Links to:

    Performance Guarantee, Service, Setup, E150 Maintenance....

  6. #6
    mtbr member
    Reputation:
    Join Date
    Feb 2005
    Posts
    783
    Hey Speci- Suspension Tech, you sound a bit different.

    Do you have a cold or something?

  7. #7
    mtbr member
    Reputation:
    Join Date
    Sep 2009
    Posts
    533
    Quote Originally Posted by Speci- Suspension Tech
    The AFR Brain and 2010 Fox manufactured Brain are very sensitive and open up very quickly to all bumps, including the initial bump and small bumps. These Brain's have platform firmness adjust, for the AFR its termed flow control. You get to determine how firm/efficient of a platform you enjoy riding with. In a softer setting the shock is allowed to be active on smooth terrain. In the firmest setting the shock will still be fully active opening up for all bumps but will have a hardtail firm platform in smooth terrain. Immediatly after the bump subsides the brain platform returns to its firm setting. The Epic has a race tuned platform it is very firm in the full firm setting, the Stumpjumper has a trail tuned platform and its firmest platform is just shy of the race tuned Epic. The earliest generation Fox produced Brain 2003-2006, an initial bump was needed to activate the Brain and then the Brain remained open for a few seconds after the last bump, the feedback that we got from this early generation allowed us to improve brain function to what it is today. Sensitive to all bump sizes, functional for the first bump and returns to its efficient setting immediatly after the last bump.
    That sounds GREAT! I'm a clyde. 6'5" 300lbs. I've read some of the other thread about setting up the bike. I'm getting a 29er SJ with brain. Since I'm a few standard deviations from a normal rider my shop might need (whether they know it or not) some help dialing in the correct settings (especially the negative compression air chamber??? in the fork). Is there the appropriate documentation for them to set my bike up for me or will I need to guide/ecourage them to get help? Also, will it be easy for me to know if it's set up right?

    EDIT:
    If my SJ FSR 29er exp XL is out there on the floor I can tell them where to ship it. I'm dying to ride it. It's a huge step up from my mis-sized 15yr old hard tail with an elastomer fork.
    Last edited by dadtorbn; 11-12-2009 at 02:47 PM.

  8. #8
    mtbr member
    Reputation:
    Join Date
    Aug 2009
    Posts
    59

    thanks

    Thanks for the replies, particular thanks to speci rep.

    I've heard nothing but negative comments from fellow cyclists since I've told them I've ordered the Specialized - mainly re the ridiculously high prices here in Aus, but also some have commented about the shocks in terms of reliability (mainly) but also the "lag" in engaging, but perhaps that is all solved with newer shocks.

    I now feel confident I've chosen the right bike for my needs and I do believe it will work as it is advertised.

    (Now if you guys could just manage to find an Aussie distributor that doesn't rip us off that'd be great.)

    Thanks

  9. #9
    Lusus Naturae
    Reputation: NoBalance's Avatar
    Join Date
    Feb 2007
    Posts
    2,795
    Quote Originally Posted by ARider
    Hey Speci- Suspension Tech, you sound a bit different.

    Do you have a cold or something?
    Ooh inside jokes! By the way, I need a new S-works Epic, please.

  10. #10
    mtbr member
    Reputation:
    Join Date
    Jan 2008
    Posts
    790
    6'5 300lbs? I'll let you lead the downhill....

    You can learn about the basic principles of suspension setup by viewing our setup videos on specialized.com support section. The RockShox fork will have suggested air pressures on a sticker for positive and negative air chambers. You can view our website for shock setup info. You will want to use a lot of rebound damping front and rear to slow down the high air pressures. I generally have the rear rebound set slightly slower than the front. Feel free to experiment with platform firmness, for the SJ family of bikes I usually suggest 3-5 clicks from full firm for the shock. The brain functions the same for all rider weights, the air spring is what is tuned for rider weight and the damping settings are set according to the air spring pressure.
    Visit my profile for Links to:

    Performance Guarantee, Service, Setup, E150 Maintenance....

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •