What signs for incorrect suspension set up?

Dr Tinkle
Dr Tinkle Posts: 49
edited February 2009 in MTB workshop & tech
I'm new on to my full suss Whyte e120. I have followed all the standard advice for fork and rear shock set up, sag etc and it all works fine. But, I'm also aware that this is just a good starting point.

Does anyone have any advice for what symptoms I should look out for to fine tune it?

Should the pro pedal adjust on my fox rear shock lock the suspension completely or as it is on mine still have some bounce?

Most confused . .

Comments

  • Pro Pedal won't lock it out, it'll just make it need more of a shove to set it going.

    If you've followed the instructions then your sag should be OK.

    You want to make sure you've enough rebound to get the fork or shock back up to full length before the next hit but not too quick that it feels like a pogo stick.

    Take your bike to a place you ride lots and just keep tweeking it until it feels good. Only turn one dial at a time though otherwise you won't know what changes worked and which didn't.
  • dave_hill
    dave_hill Posts: 3,877
    It's probably easier to tell you what should happen, rather than what shouldn't happen. But even that's a bit vague.

    Simply, what should happen is that you shouldn't notice your suspension working once it's set up correctly.

    Hmm. But the definition of "correctly" depends on a lot of things - not least, how you like the suspension set; how you ride; how heavy you are; and where you ride/what type of riding you do.

    I'm afraid that it's one of those "how long is a piece of string?" questions...
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  • XxxBFGxxX
    XxxBFGxxX Posts: 1,355
    dave_hill wrote:

    I'm afraid that it's one of those "how long is a piece of string?" questions...


    are but i can answer that one mate. its twice the length from the middle to the end. Now can i have an answer pls. lol only jokeing chap.
  • Just play with it on the trails until it feels right, takes a few runs to see what kind of response you are looking for.

    For setting sag I set it to the recommended level at home and then take a note of what travel I use (from travel indicator) if the sag is right by the book but in real world full travel is not being used then i'd let some air out so that the sag is set for the conditions I ride in. Being just under 10st and a light lander I find I have to have more sag than required.

    As for rebound, again this depends on the trails you ride. The Kona is used for Derbyshire only, so predominantly rocky descents with mulitple quick hits. I compensate for this by running quicker than normal rebound meaning I have to land the bigger drops using my body to absorb the landings.
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  • I'm almost in agreement with Dave except...

    ... the brain adapts to what its given, so you can end up not noticing how poorly a suspension setup is working because you have got used to it.

    I've got an E120 myself. The suspension is sag sensitive. The suspension is designed around one particular sag setting and it takes very little variation from the recommended sag value of 14mm to end up with something that isn't working optimally. The caveat is that sag readings can be quite difficult to do accurately and can be affected by seating position. Go with 14mm sag to start with and don't stray too far in either direction.

    The shock should be run with propedal off for 99 % of your riding (even most climbs). The bike is designed to have active suspension even while climbing. You won't be getting the best out of the bike by running propedal. If you find you are losing a lot of pedaling energy into the suspension, this may be a hint that the suspension is a bit low.

    Rebound has one correct value. It should be not too fast and not too slow. If you push down on the saddle of the bike and watch the rebound, the settings should allow you go all the way from pogo stick to marshmallow. You want a setting somewhere around the point where the rebound stroke is just getting visibly slower than an undamped pogo stick.

    I don't know which fork you have. Forks are a topic in themselves, but should be set to match the rear suspension of the bike to give you an even response, front and rear. If the fork washes out on corners it is often because the rebound is too fast. I start off with too fast rebound and gradually slow it down until the fork doesn't wash out on corners.

    Riding position can also affect fork performance massively. You need to make sure you've not got anything funny going on with bar height and stem length. You want to have a nice relaxed "attack" position where you have lots of room to manoeuvre from a neutral position in the centre of the bike.

    The E120 has short chainstays. It is easy to end up too far back on the bike. It is designed around an in-line seatpost and this is what you should have. Keep the saddle fairly central on its rails. On large size E120s they fit a 100mm stem. This didn't work for me and I reverted to 90mm. I keep the bars pretty low because the front end of the bike is high enough.

    I hope that helps.
  • jairaj
    jairaj Posts: 3,009
    All of the above seems like pretty good advice.

    suspension set up is a personal thing. use the manufacturer manuals as a guideline and play around with the settings. Just fiddle one setting at a time and have a little go on the bike and see how it feels, do you feel more comfortable / confident? If so keep it there, if not try the opposite?

    You will soon understand how all the bits work together and achieve a better understanding of what to tweak and when to tweak it.
  • Daz555
    Daz555 Posts: 3,976
    It is also useful to see how much travel you are getting with any particular setup. Rear shocks often come with a o-ring that lets you see how much travel you are getting. A zip-tie on the fork does the same.

    As others have said, only ever change one thing at a time. From my perspective and having no previous experience I did the old "set everything in the middle" and stared from there. Sag first, and then moved onto rebound damping and I;d recomment setting sag in the standing 'attack' position. My fork has no variation on compression so nowt for me to do there.
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  • This has all been really useful, thanks alot to all of you.
    Petercam - I took it out today to my local route at Swinley Forest and tried riding it everywhere with the pro pedal turned off. Felt very bobby on the climbs so will adjust the sag settings first.
    Also finding that on relatively smooth, muddy decents when braking hard, heels down compressing forks to stop sliding, front feels very 'springy' and almost out of control. Does this suggest the damping is returning too fast? I hear that Fox floats are not as stiff as others, is this just the result of that?
    And just to be sure, when you mention a fork ' washing out on corners' is this front wheel slide because I'm getting alot of that?
  • jairaj
    jairaj Posts: 3,009
    Dr Tinkle wrote:
    Also finding that on relatively smooth, muddy decents when braking hard, heels down compressing forks to stop sliding, front feels very 'springy' and almost out of control. Does this suggest the damping is returning too fast?

    this could be due to incorrect compression setting too? Do you find under hard braking that the front compresses a lot? if so, you might want to change the compression settings a bit to stop the front diving down under breaking? the front will naturally compress a bit under breaking but should not dive down drastically.

    * edit: this is assuming your fork has compression adjustment
  • supersonic
    supersonic Posts: 82,708
    Low speed compression damping will indeed effect fork dive. Not always adjustable on all forks.

    I would also be a bit wary of setting rebound up based just on cornering wash out, as are introducing other factors here. Washout can be a result of head angle, tyre grip, riding style. I would be more inclined to set it over a series of bumps, finding a setting that doesn't pack down over them, but not too fast as to pogo back. Also some people naturally prefer a slightly faster or slower rebound.
  • Dr Tinkle wrote:
    This has all been really useful, thanks alot to all of you.
    Petercam - I took it out today to my local route at Swinley Forest and tried riding it everywhere with the pro pedal turned off. Felt very bobby on the climbs so will adjust the sag settings first.

    I ride Swinley Forest too. I could take a look if you're going to be there any time soon.

    Supesonic's words on my previous recommendation of the wash out is fair comment. So often though on these forums, advice is given on "packing down" and stuff like that that I just don't think describes what I feel while riding a bike. I feel a front end having too little grip. I feel it being harsh (probably packing down, but could be other causes). I don't feel "packing down" as such except as harshness. YMMV.

    For all that some people prefer faster or slower rebound, you are still talking within a narrow range of values for the same riding style. If you're into landing big drops, slow rebound may just keep you on your bike. If you're riding around Swinley Forest on an E120, you probably want a fairly normal "trail" setup. If you're asking the questions you're asking on this thread, you need some "safe settings" from which to experiment. We should be able to get you to that point.

    How much riding experience do you have? How much full sus experience do you have? The fork feeling bouncy on a descent could be down to damping settings or it could be air pressures too low or it could be that you're not entirely comfortable with the level of suspension the bike is going to be giving you. All of these are fixable. I've also noted your comment on the the bob while climbing. Sounds like a quick look see to assess your current settings may save a bunch of time.

    FWIW, I weigh about the same as you (seen you mention 14+ stone on another thread) and ride a large E120. Our setup requirements may be quite similar.
  • supersonic
    supersonic Posts: 82,708
    Good words Peter, very much agree.
  • I really appreciate the offer Petercarm. I think meeting up over at Swinley would be a great idea, good to put a face to name too. I was there a day or so ago but pulled out because it was so flooded from the thaw water. Dont like to damage the place unneccessarily so might be heading back in the next week or so.

    I'd consider myself late begginer going intermediate skill wise, been riding hardtail for 3 or so years but new to full suss in last 6 months.

    I've been fettling since your last comments because the front and rear settings didn't seem balanced for rebound which seems to have given me more of a starting point. Also upping the pressure in the rear a little. I had 15mm sag which seemed about right but I'll start a little stiffer now and work back I think.

    Jairaj - Fork dive doesn't seem to be an issue, its more a general instability under load. From the comments sorting the rebound seems key but Supersonics comments on head angle etc have got me thinking about the cockpit set up.