Compression damping with Turnkey

declan1
declan1 Posts: 2,470
edited March 2014 in MTB workshop & tech
Hello again - sorry for all these questions.

My XC32 solo air fork is set up for 20% sag and is nice and plush at that setting but it blows through its travel very easily and almost bottoms out on hard braking. I previously fixed that by adding 30psi but that reduced the sag quite a bit and made the fork quite 'nervous' on the trails.

Now, I know hardly anything about forks and damping and whatnot but from what I can gather low-speed compression damping helps with brake dive and stops a fork from using all of its travel too quickly.

My forks have the Turnkey damper with a poploc (I think) remote. I've just tried holding the remote at a certain position between open and locked-out and it feels very much like my dad's Recon Gold with some low speed compression (motion control knob turned towards lockout a couple of clicks).

Is this safe/will it ruin my fork?

Thanks!

Road - Dolan Preffisio
MTB - On-One Inbred

I have no idea what's going on here.

Comments

  • jimothy78
    jimothy78 Posts: 1,407
    No, it won't harm the forks, but it's hardly an ideal solution.

    The basic workings of the compression damper are the same, in that turning the dial (whether with the remote cable or the knob) closes off the holes through which the oil flows. The difference between the remote version and the non-remote is that in the remote version there's a spring to return it to the "fully open" (least damped) setting when the remote is released, and you effectively only have access to two positions - open and closed (the "poploc adjust" remote has a dial that allows you to set the "open" setting to be less than fully open - a bit like you applying a little tension to the cable as you describe).

    There's a few things you can do:

    First - check the level of oil in the damper circuit is exactly right - my forks were divey in the open setting when I first used them, but it turned out the fluid level was a bit low, and they're much better now it's been corrected.

    If the oil level is right, but you're still not happy with the amount of support you're getting, then you could:

    a) get a poploc adjust remote, to give yourself a bit of fine control over the "open" setting
    b) replace the remote with an old thumb-operated gear-shifter (looks slightly clumsy, but works surprisingly well, and gives you a range of compression damping levels to choose from)
    c) take the remote off, then take the damper out and either disengage or remove the return spring, which lets you run it without the remote, and essentially gain access to the whole range of damping levels - you can then just use the dial as a knob, or buy the official knob as an extra.

    hope this all makes sense!
  • Have a look here the suspension tuning theory guide is quite comprehensive . Other guides here will also help on your fork specifics. http://www.sram.com/service/rockshox/7
  • declan1
    declan1 Posts: 2,470
    Thanks for the replies, very helpful! :)

    With the Turnkey damper, is moving the lockout lever between unlocked and lockout low-speed compression or high-speed?

    Road - Dolan Preffisio
    MTB - On-One Inbred

    I have no idea what's going on here.
  • jimothy78
    jimothy78 Posts: 1,407
    It's a single compression circuit, so increasing the damping affects both high- and low-speed compressions (although I think it's designed to have a greater effect on low-speed (like pedal bob) than high speed (trail roughness), as this increases pedalling efficiency and support under braking without adversely affecting grip so much).

    Be aware, though, that everything we've talked about so far has nothing to do with the "Turnkey" technology - that's purely to do with the "floodgate" over-ride system which allows the damping circuit to be opened if you take a big hit while riding locked-out. Having a "turnkey" simply allows you to fine-tune the level of impact where this over-ride kicks in with the little silver dial (non-turnkey systems either have tooled, or no adjustability of this level) - it's nothing to do with the "normal" function of the forks or the damping circuit.
  • declan1
    declan1 Posts: 2,470
    Ah right - I thought the adjustable blow-off was called Floodgate?

    Is it possible to replace the current damper with a Motion Control unit from, say, a Tora in my XC32 (solo air)?

    Road - Dolan Preffisio
    MTB - On-One Inbred

    I have no idea what's going on here.
  • jimothy78
    jimothy78 Posts: 1,407
    declan1 wrote:
    Ah right - I thought the adjustable blow-off was called Floodgate?

    It is - like I said before, the "turnkey" bit just means being able to adjust the floodgate without a tool.
    Is it possible to replace the current damper with a Motion Control unit from, say, a Tora in my XC32 (solo air)?
    It's possible to replace the damping circuit across different models (although I can't remember which models are compatible with which off the top of my head). But there's really no need to in your situation.

    Have you checked the oil level yet? This may rectify the problem you're having, and if it doesn't, then dis-engaging the spring and fitting the crown-mounted knob will have exactly the same effect as installing a different damper, but for a fraction of the price.
  • declan1
    declan1 Posts: 2,470
    Thanks for that info - I'm going to use a 7 speed mtb shifter to control the compression which should be better than zip-tying the poploc lever down!

    I'm really not confident checking oil levels as I don't really know how the forks work - an air can service on a rear shock is about the limit of my knowledge :P

    Road - Dolan Preffisio
    MTB - On-One Inbred

    I have no idea what's going on here.
  • The Rookie
    The Rookie Posts: 27,812
    Read the manual, oil level (or amount) is one of the easiest jobs going.

    A friction lever is a better bet than an indexed.....
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • supersonic
    supersonic Posts: 82,708
    Turnkey is not an adjustable floodgate system, the blow off is fixed. Turnkey is designed to be an on/off lockout system, there is no compression adjustment like there is work motion control. Setting the dial mid way does very little and makes the fork somewhat clunky.
  • jimothy78
    jimothy78 Posts: 1,407
    supersonic wrote:
    Turnkey is not an adjustable floodgate system, the blow off is fixed.

    really? I've badly misunderstood something along the way, then. Apologies to the OP if that's the case.
  • declan1
    declan1 Posts: 2,470
    supersonic wrote:
    Turnkey is not an adjustable floodgate system, the blow off is fixed. Turnkey is designed to be an on/off lockout system, there is no compression adjustment like there is work motion control. Setting the dial mid way does very little and makes the fork somewhat clunky.

    Ah, ok. I'll probably leave it with the lockout fully open then - if I put more air in it feels pretty good but there's just not enough sag. I'll probably save for a Recon or Reba soon anyway.

    Thanks for all the help! :)

    Road - Dolan Preffisio
    MTB - On-One Inbred

    I have no idea what's going on here.
  • Cqc
    Cqc Posts: 951
    Not sure if this is the same for your forks- but for me ( fox float RL) if I add oil into the air chamber it becomes more progressive and is a 5 min job. If you have an open bath damper, Then checking the oil levels is actually easier than an air can service, if sealed its harder. Good luck.
  • Oil level in right hand damper check is very easy. Just need allen keys and a 24 mm socket. Can do on bike . It's well worth doing . My sid fork was low on oil from new , something I have found quite common on reading . My link above will give you info .
  • declan1
    declan1 Posts: 2,470
    Thanks for the advice - I'll probably attempt checking the oil level sometime soon as a more progressive spring rate is definitely what I want. I think the fork was sitting at about 10% sag when it felt a lot better so for the moment I'm going to put the pressure back to what it was!

    Road - Dolan Preffisio
    MTB - On-One Inbred

    I have no idea what's going on here.