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  1. #1
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    2011 SJ FSR 29er - Help me with tuning the suspension front and back

    Hi All, i posed this question in the suspension forum and have gotten some good general ideas. I am hoping for some specifics if at all possible. There are many adjustments for the new 2011SJ FSR 29er so any specifics on how to setup the suspension would be great!

    Just a got a new Spech SJ FSR 29er. The shop quickly setup the suspension but i want to learn to tweak it more. Furthermore the owners manuals are pretty useless. I weigh 190 lbs - for the front reba rockshox they added 150psi instead of the recommended 130. Cant remember what they put in the back with the brain.

    Bottom line the front o-ring only shows me using about 60-70% of the travel even though the sag was correct. For the rear i have used about 75% of the travel. This is after two pretty hard rides - 25 miles with some good rock sections.

    I have read that the suspension should bottom out once on a good ride otherwise its too firm and you are not using it all - do you guys agree with this?

    Finally do you have any tips or links to help me fine tune this suspension?

    Thanks so much!!

    if this link works you can see the o-ring of the front fork in the image

    http://gallery.mtbr.com/showphoto.ph.../ppuser/515737

  2. #2
    JTP
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    try these settings

    Air pressure:

    Rear Fox future shock 200 psi
    Reba 125 psi in possitive/125 in negative

    Rebound:

    Front 5 clicks out from full slow
    Rear 5 clicks out from full slow

    Brain 3 - 5 clicks out from full soft depending on climbing vs desending

  3. #3
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    Thanks JTP for taking the time to respond- I will give it a shot. Actually i think i have it setup very close to what you list except the front shock having too much air

    Any other have any suggestions?

  4. #4
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    triad pressure

    I found that I lose 50 psi in the triad when I disconnect the pump. I just cant unscrew the nozzle fast enough. I know some people will say that it is just the air escaping the hose on the pump, but when I reconnect it it always shows 50 psi less. Maybe I'm losing the 50 psi during the reconnect, but over pumping the shock has produced a much better ride and the correct sag on the "sag-a-tron."

    2 cents...

  5. #5
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    Have you got your own shock pump? It's worth finding a section of trail that you can ride repeatedly whilst making adjustments until you find settings which suit your riding style.

    This is a setup guide I copied and pasted from another site that explains the procedure.

    My New S-work Epic impressions

  6. #6
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    Ok, thanks for the help so far. I just bought the shock pump and reduced the front fork air to about 125 from 150 (both sides). The back was 200psi and i left it there. I double checked the rebound settings as well.

    Today i will ride around the parking lot, go over a few cement parking curbes and see where I am. hopefully tomorrow I can ride and then change as needed. Hopefully once i get this set i wont have to worry much more about it.

    The only concern is the rear sag seems a little high and its hard to get a consistent reading - it just depends on how you get on and off your bike - a little extra push makes a big difference. The back also feels really soft.

    But thanks again - I will let you test and post what numbers I settle on

  7. #7
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    Have you got a 2011 Stumpjumper FSR 29er Expert or a 2011 Stumpjumper FSR 29er Comp? They have different rear shocks so it would be useful to know which you have.

  8. #8
    Bike Breaker.
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    There's some great tips on the fox site.

    http://www.foxracingshox.com/protune...s&video=setsag

  9. #9
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    Sorry, one more question

    For the front fork - do i set any compression at all?

    I thought that was just to lockout for a climb or something - but i guess it does say compression so in theory i should have it somewhere in the middle. Let me know how you guys have it set up

    thanks!

  10. #10
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    i have the expert with brain

    Quote Originally Posted by WR304
    Have you got a 2011 Stumpjumper FSR 29er Expert or a 2011 Stumpjumper FSR 29er Comp? They have different rear shocks so it would be useful to know which you have.
    i have the expert with the brain - thanks

  11. #11
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    It looks like your bike has a Rock Shox Reba RLT fork (rebound and compression adjustment) and the Fox mini brain rear shock.

    Before you start trying different settings make a written note of what your current suspension settings are. That way you have a known baseline to apply again if you're unsure whether the changes you make when testing are actually an improvement.

    There's a lot less information than you'd expect about how to set these dual air forks up properly.

    Here are a couple of links I found that may be useful:

    http://www.bikeradar.com/forum/viewtopic.php?p=15390712

    http://fuzzz.gaulin.ca/2007/07/29/di...ba-like-a-pro/

    http://www.bikemagic.com/forum/forum...last/1/V/2/SP/

    Common Fork and Rear Shock Dial Adjustments
    Rebound or Compression damping adjustments are usually referred to in most setup guides as being from "full fast" through to "full slow". "Full fast" rebound is when the red rebound dial is turned fully counter clockwise and means the suspension will return to its starting position quickly after it has been compressed. "Full slow" rebound is when the red rebound dial is turned fully clockwise and means the suspension will return to its starting position slowly after it has been compressed.

    The Specialized Brain platform settings are usually "full firm" through to "full soft". "Full firm" brain adjustment is when the blue brain dial is turned fully clockwise. This setting has the most brain platform so the shock or fork feels as though it is locked out until you hit a bump. "Full soft" brain adjustment is when the blue brain dial is turned fully counter clockwise. This setting is the least amount of brain platform and the shock can move freely.

    The starting point for testing settings needs to be making sure that the fork is completely unlocked with the lock out lever set to fully open and a fairly neutral air setup between the two chambers. If there's a seperate compression damping adjustment (the product page implies there is one) then that needs to be full fast, along with the rebound being set to full fast.

    Rock Shox Reba RLT Specification
    http://www.sram.com/rockshox/products/reba-rlt

    You then need to set the fork air pressure, followed by the compression damping and then the rebound damping in that order. Air pressure - compression damping - rebound damping.

    The rear shock should be a bit easier as it has fewer settings. The starting point needs to be making sure that the brain is full soft so there is no platform (turn the brain dial fully counter clockwise) and that the rebound damping is full fast (turn the rebound dial fully counter clockwise). When setting up the brain shock's air pressure/ sag and rebound damping do it with the brain set to full soft. Air pressure - rebound damping - brain platform.

    The main thing is to get a good consistent handling balance between the front and rear suspension.

    My New S-work Epic impressions
    Last edited by WR304; 01-31-2011 at 04:02 PM.

  12. #12
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    thanks so much for the time WR304

    yes there is so little info on this fork its amazing. Well i did some testing outside - ran into some cubes and other potholes and it felt good. all this after only lowering air from 150 to about 125 in the front top and bottom.

    I will do the rest on the trail

    But from the hits i did outside i used about 70% or so front and rear so i think the air pressures are better

  13. #13
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    I also have the SJ FSR Expert 29er, but I weigh 160 lbs.

    For the rear shock, I used the recommended pressure in the manual for my weight. This got the sag at 10-11mm, which is just right. I set the brain about 5 clicks from full firm for most trails. On the really gnarly non-stop rock garden trails I'll go to 7 clicks to make it more active. I don't get full travel during a ride, but it works well for climbing efficiency and for smoothing out the rocks and roots so I haven't messed with it.

    For the Reba RLT I like the pressure a little higher than what is recommended on the chart on the fork leg. I'm used to riding a rigid or an old Mag21 fork, so I prefer a firmer front end. I still get nearly full travel, though. I have been setting the + and - pressures equal for small bump compliance, but I am now experimenting with the neg. about 5 to 10 psi less than the pos. I leave the compression/lockout full soft except I set it full firm for some of the longer climbs -- I really just use it as an on/off switch. I still don't feel 100% dialed in, but it works pretty well overall.

    I welcome any other input or data points from others with this bike.

  14. #14
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    Quote Originally Posted by jabrabu
    I also have the SJ FSR Expert 29er, but I weigh 160 lbs.

    For the rear shock, I used the recommended pressure in the manual for my weight. This got the sag at 10-11mm, which is just right. I set the brain about 5 clicks from full firm for most trails. On the really gnarly non-stop rock garden trails I'll go to 7 clicks to make it more active. I don't get full travel during a ride, but it works well for climbing efficiency and for smoothing out the rocks and roots so I haven't messed with it.

    For the Reba RLT I like the pressure a little higher than what is recommended on the chart on the fork leg. I'm used to riding a rigid or an old Mag21 fork, so I prefer a firmer front end. I still get nearly full travel, though. I have been setting the + and - pressures equal for small bump compliance, but I am now experimenting with the neg. about 5 to 10 psi less than the pos. I leave the compression/lockout full soft except I set it full firm for some of the longer climbs -- I really just use it as an on/off switch. I still don't feel 100% dialed in, but it works pretty well overall.

    I welcome any other input or data points from others with this bike.
    It is amazing that there is so little data out there

    Well i now have the pretty much exact recommended pressures for my weight (190lbs). I rode a not very hard place yesterday but it was long and there were some small jumps and drops and about 1400 feet of climbing. I used about 70% to 75% total travel and with pretty neutral rebound settings it felt good though I will test more with the rebound.

    I have the brain 4 clicks from soft and I will tell you that if you stand up and hammer climbs you waste energy with the rear and front suspension. No problem though - i sit and spin circles and have no problem. So I am trying to go as soft as I can without bobbing around and I think having a smooth pedal stroke helps. Even the super steep hills i spin most of the way and only stand when i really need to

    One other note - the stock air pressure is low on the seatpost and buyers should expect to increase that air pressure otherwise the post wont rebound all the way - i think it needs about 40psi with a shock pump

    Finally - I am on flats and cant believe how good of circular stroke I can get with these - with the pins and 510 shoes its very sticky!

  15. #15
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    I have more of a sit and spin style anyway, even on my rigid bike. I do hop up out of the saddle on very short climbs and on super steep climbs, though. I find that I get more bobbing from the front fork than from the rear -- the Brain really seems to help. If I crank up the lockout on the fork the bobbing is tolerable. Even when standing out of the saddle, I have found that I can smooth out my pedal stroke to minimize the bobbing.

    I haven't messed with rebound yet. The recommended settings feel pretty good to me. I might try a little faster rebound up front, though, to make the forks more responsive in the rock gardens where you get lots of hits in rapid succession.

    I also find the command post return a little sluggish, especially in cold weather. I should add a little air pressure. I also found that wiping a little bit of lube on the post helps. I apply some chain lube and then wipe it clean with a rag. I haven't found much use for the command post, though. I've tried lowering it to the middle position on longer technical descents, but it just feels awkward to me. It is handy for lowering the seat when putting the bike in my SUV, but that's about it. I might swap it for a regular post to save the weight.

  16. #16
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    Did you get a manual with your fork explaining what the settings do? There isn't one on the Rock Shox site that I could see.

    On your 2011 Rock Shox Reba RLT fork (without the remote lock out) there should be three adjustment settings on the right hand leg. The rebound damping adjustment is the dial located at the bottom of the fork leg.

    On top of the fork leg you have two linked settings consisting of a blue lever (compression damping) and a gold knob (floodgate).

    Unlike some other forks (eg: Fox F100 RL) the blue lever isn't purely a lockout. It's an adjustment in itself. You can fine tune the bump force required to activate the fork by using varying combinations of positions between fully open and fully locked out.

    As you gradually turn the "floodgate" knob it looks like it increases the bump force needed to override the lock out. Full open means the fork is completely open and active. As you turn the knob the fork will become increasingly unresponsive to smaller hits. When turned fully the fork should be locked out almost completely. Page 25 of the 2011 Rock Shox Reba service manual defines which dial is which: (The manual doesn't say whether it turns clockwise or anti- clockwise though. It should be easy to work out by experimenting to see how the fork feel alters. )

    http://www.sram.com/_media/pdf/rocks...cal-Manual.pdf

    Have a look at this thread about Rock Shox Reba settings that daniyarm linked also:

    Rock Shox Reba setup
    Reba fine tuning

    "The 1st thing to remember about the floodgate (FG) and compression settings on Motion Control RS forks is that the 2 settings are interlinked. If either the FG or comp or both are set to full open, there is no tangible effect on the compression or 'platform' performance of the fork. E.g. with FG full open and comp full closed settings, there is no tangible diferrence in the compression damping characteristics of the fork. Compression damping in this instance is basically of the low-speed variety, i.e. the speed at which the fork compresses as a result of a low-speed event e.g. pedal bob. FG provides a threshold at which the damping effect is reduced and the fork is allowed to compress more easily (large bump, etc.)

    In order to use the comp & FG settings effectively, you will need to have both settings engaged at the same time to some degree that suits your riding style. The slight trick is that each setting (FG & comp) influences how the other behaves. I don't really know how best to explain this, but perhaps I shall instead list 2 popular settings I have noted on the boards as a reference point, and you can experiment from there.

    Example setting #1 - Comp 1/2 to 3/4 closed + FG 1-2 full turns from full open
    This setting provides 'more' low speed compression damping performance, with a 'light' FG threshold resulting in a mild platform effect. This config seems to give some anti-brake dive/bob performance, whilst maintaining reasonable small bump sensitivity. This is the setting I personally prefer.

    Example setting #2 - Comp 1/4 to 1/2 closed + FG 1-2 full turns from full closed
    This setting provides 'less' low speed compression damping performance, with a 'strong' FG threshold resulting in a stronger platform effect. This config seems to give better anti-brake dive/bob performance, but resulting in a harsher ride. This seems to be preferred by some riders on the forum, and may give better performance for those who prefer to hammer or want a strong platform effect.

    Additionally, you can also crank up the compression knob (or fully depress to lock for poploc) temporarily to provide a 'lockout' for climbs or when you want to get up and hammer it. It isn't a 100% lockout, as the fork will still compress once the FG threshold is reached, which means that you will still have suspension if you forget to 'unlock' on the way down the hill.

    There are obviously infinite variations of the above, and the final settings will depend on your own riding style and preferences. The only thing I can suggest is to go with a setting you think is best for your and tweak it from there on a familiar trail - I highly recommend small incremental adjustments when tuning, as a single click on the FG can be felt. For further reading, please refer to The end-all explanation to Motion Control Damping..."
    Pongee

    Reba fine tuning

    Pictured below: Rock Shox Reba RLT (non remote lock out) floodgate and compression damping adjusters
    Attached Thumbnails Attached Thumbnails 2011 SJ FSR 29er - Help me with tuning the suspension front and back-rockshox_reba_floodgate.jpg  


  17. #17
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    Wow

    Wow thats a lot of info - thanks so much for taking the time to post and help me out here!

    I read through that long post - goes back about 5 years and was really helpful. Looks like for air pressure go lower than the recommendations and keep it even or go about 10psi higher on the +. Ill give it a shot - first i will go down to 115 in both then try something like 120+ and 110-. BTW - it felt great going from 150psi down to about 125 - so maybe another 10 PSI will get me more travel

    Also, the manual is worthless. Seriously it does not even mention the air pressure! Nothing about anything - hard to believe that the manufacturer wont give suggestions on their fork settings. AlI you get is the sticker on the fork with the PSI numbers and thats it

    Finally i know about the compression lockout but thanks for pointing out that other setting. I will work with air-pressure and rebound first but maybe later I will tinker with the other settings and hopefully soon I wont have to do anything.

    thanks!

  18. #18
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    I was at the bike shop today (dropping off my broken Specialized fork to be repaired) and had a look at the Rock Shox forks on some of the show bikes whilst I was there. They didn't have a Reba RLT on display so I had a look at a the Revelation RL on a 2011 Stumpjumper FSR comp carbon (no floodgate dial) and a Sid RLT with the pushloc remote on another bike.

    The compression lever on the Revelation RL stiffened the fork up a bit but turning it fully was nowhere near a full lock out. Compared to the lock out lever on a Fox F100 RL it still felt active with the lever turned to full compression. The fork made a nice loud squishing noise on part compression though.

    The Sid RLT with Pushloc fitted to the show bike was really odd. The fork felt exactly the same with Pushloc on and off when pushing down on the fork. The floodgate dial didn't seem to make any difference either. It wasn't a very good test really as I couldn't tell whether the settings were doing anything. Perhaps the fork was broken?

    Do the floodgate/ compression settings on your fork make a noticeable difference when you change them?

  19. #19
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    On my Reba RLT the compression setting makes a very noticeable difference. When I turn it up all the way the fork doesn't compress much at all and feels harsh on rocks and roots. When turned part way it is medium firm and makes squishy noises. When fully off the fork is most active and most plush.

    I've always just used the compression adjuster as an on/off switch, leaving it fully soft most of the time and then cranking it all the way up for some climbs. My trails have a lot of roots and rocks, so I want the fork fully active most of the time. But based on some of the posts above I'm going to try setting the compression and floodgate to middle settings and see how that works. Hopefully it will provide some anti-dive and pedal platform and still be plush enough in the roots and rocks.

  20. #20
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    Here is what i found WR304

    ok guys - here is what i found out after experimenting

    Yes the fork stays active with the compression/lockout all the way on. But you can adjust how active it is with the floodgate. Like you mentioned WR304 - the compression/lockout is linked to the floodgate. If you have the compression/lockout off (all the way to the left) then the floodgate has no effect on the shock. To adjust the floodgate you just twist a knob on top of the compression/lockout - its very fast and easy

    So what i did today was adjust the floodgate to the middle - it has like 36 clicks total! So about 16-17 clicks in is where i have floodgate. When the compression/lockout is on it really helps for climbs but is still a little active (2 inches or so of travel but you have to hit something to use it). One time after a climb i left it lockout out on during the rocky downhill and barely noticed!

    BTW - i weigh about 190 suited up and have the front + and - air pressure at 125psi - 150 was too much and 110psi was too soft and gave me bad brake dive. So now at 125psi i only use what seems like 75% of the travel but i prefer it stiffer actually - especially when going down steep rocky sections

  21. #21
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    Quote Originally Posted by surftime
    So now at 125psi i only use what seems like 75% of the travel but i prefer it stiffer actually - especially when going down steep rocky sections
    With a relatively long travel 130mm fork like your Reba the effects on the handling of the suspension compressing and rebounding are more noticeable than with a shorter travel fork.

    If the suspension fork sits too far down into its travel then it effectively steepens the head tube angle, making the bike's handling more twitchy.

    When the fork is heavily compressed it also shifts your weight distribution forward onto the front wheel, unbalancing the bike.

    By having a stiffer suspension setup it means that the fore-aft weight distribution and handling changes should be less dramatic, keeping the bike's feel consistent and predictable. This is especially noticeable under heavy braking if your fork setup is quite soft.

    Here's an example of what happens with an overly soft fork:

    You're on a fast descent and the bike is working well soaking up the bumps - you come up to the corner braking zone and hit the brakes hard as there's plenty of traction. As you begin braking the front fork dives down into its travel throwing your weight forward, lightening the rear wheel, unbalancing the bike and making it a bit squirelly. In response you have to either release the front brake slightly, or push your weight further back over the rear wheel. As you come up to the corner entry your weight is a long way back behind the saddle, and you're still hard on the brakes - not an ideal position for cornering.

    You have to get off the brakes before corner entry, in order to try and let the suspension even itself out before the corner. This is so you can shift your weight forwards enough to load the front wheel and outside pedal and carry the speed through the corner. If you try and take the bend with your weight still far behind the saddle there isn't enough load on the front wheel to stop it understeering or washing out. This compromises your apex speed, along with your corner exit speed.

    If you come up to the same corner with a stiffer front fork the response is different. When you hit the front brake there's less brake dive, meaning that you can brake harder without needing to push your weight as far back. You can trail brake and carry more speed into the corner because your weight distribution is closer to where it needs to be whilst cornering. The bike's handling balance has stayed closer to neutral throughout the sequence of braking - corner entry and corner exit boosting your confidence that the bike is predictable and won't do anything unexpected.

  22. #22
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    Quote Originally Posted by surftime
    One time after a climb i left it lockout out on during the rocky downhill and barely noticed!
    I definitely notice if I forget to turn off the lockout. I'll notice that it feels a lot more harsh which makes me realize that I forgot to turn the knob back.

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