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My old xc bike is faster than my newer full suss :(

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  • oxomanoxoman Posts: 8,867
    Don't expect full lockout to stop all shock movement.
    Too many bikes according to Mrs O.
  • danlightbulbdanlightbulb Posts: 660
    How much difference would I expect to see between operating a shock in pedal mode compared to in a full lockout mode (which I note might still allow a bit of flex)?

    Or is it going to come back to the weight again -1.5kg difference between my two bikes - how much difference is that making?

  • The RookieThe Rookie Posts: 27,748
    Sorry yes, the RT3 has a fixed threshold my bad.

    Yes the RP23 is an older shock, the modern version is the Float DPS 3-position lever.
    https://www.ridefox.com/family.php?m=bike&family=float
    However the RP23 is a really reliable shock, can be found used for circa £50-80 and even with a full service you get an almost as new shock a lot cheaper.
  • danlightbulbdanlightbulb Posts: 660
    edited July 2020
    You guys were right - my shock was set too low.

    Running at 220 psi yesterday was loads better. Used about 80% of the travel so arguably its a little high at 220 but the climbing was better.

    It does bob in pedal mode. Sag in pedal mode is about 10-15% with about a 5% bob when pedalling. I can feel that pedalling efficiency being lost a little, compared to my hardtail bike.

    So i could do with making a decision now - would I benefit from a shock with a stiffer lockout? Sticking with Rockshox either an RT3 which has 3 modes or an RL which has 2?
  • steve_sordysteve_sordy Posts: 2,139
    edited July 2020
    I believe in getting the best out of whatever suspension I've got before I start swapping it out for more expensive kit.

    I have had shocks of different makes and complexity. I've had a Fox RP23, I've had a Rockshox Deluxe RT3 and I've had simpler ones. The one I've got right now is a RockShox Deluxe R Debonair. In other words it has a slightly larger air chamber and has low speed rebound damping adjustment only. It has no high speed rebound, no high speed compression damping adjustment and no low speed compression adjustment (the feature you are looking at adding).
    I set the sag at 28% for starters (because they all seem to end up there for me in the end). Straight away I was unhappy with how rapidly the shock used up its travel. I never once felt it bottom out though. I was about to open it up and add one or more bottomless tokens when a mate lent me a ShockWiz.

    https://www.mbr.co.uk/reviews/tools/quarq-shockwiz-review

    I spent two days with the ShockWiz, just on the shock. I ragged the censored off the bike and really put the shock through its paces.

    I expected the ShockWiz to tell me that I needed some air spring volume adjustment but not so. It recommended that I add some rebound damping and that was it! (So I'd got it almost right all by myself! :) ). After my final run the ShockWiz said that baseline psi, air spring ramp, LSR, HSR, LSC, were all OK. It suggested that the HSC should be made less firm. (I can't alter it, but maybe something for the next shock service?) The ShockWiz also reported that potential suspension problems such as Pogoing, Packing, Bottoming, Bobbing, and Bouncing were all OK.

    So there was nothing wrong with the shock. I didn't have to tell the ShockWiz what shock I had, all it needed to know was the compression ratio (ratio of the volume of the shock open and fully compressed) which was established at the start of ShockWiz set up.

    So I forgot about the shock for 3-4 months. But I later added one token to the air spring to reduce its volume and increased the sag to 30%. I believe that it is noticeably better. It does not use up as much travel, yet is softer over the roots and small rocks.

    I have no intention of spending any money on the shock, because I'm happy with its performance. However, after a similar amount of time evaluating the fork, I spent £300 converting the Revelation RC Debonair to a Pike Ultimate by changing the Motion Control damper to the Charger 2.1. I went for the RCT3 not the RC which would have been another £100. It wasn't the extra money, but the fact that the design of the offering for the user was much more complex and I decided to be strictly honest with myself and decided that I was more likely to get value from the RCT3. It is an amazing upgrade! <3
  • steve_sordysteve_sordy Posts: 2,139

    You guys were right - my shock was set too low.

    Running at 220 psi yesterday was loads better. Used about 80% of the travel so arguably its a little high at 220 but the climbing was better.

    It does bob in pedal mode. Sag in pedal mode is about 10-15% with about a 5% bob when pedalling. I can feel that pedalling efficiency being lost a little, compared to my hardtail bike.

    So i could do with making a decision now - would I benefit from a shock with a stiffer lockout? Sticking with Rockshox either an RT3 which has 3 modes or an RL which has 2?

    I can't believe that you have got this far and only now discovered that the basic sag setting was too low. Yes, I know that new forks and shocks can be a bit sticky, making %sag a bit of a lottery. That is why they are always a starting point. Once you ride the bike, you alter the settings (one end at a time) until you are happy with how it rides. Then after an interval of a month or less, you take a fresh look.

    After the time has passed for the newness to have gone, the suspension should be operating at peak. If you are still having problems with stickiness, then I suggest that you do a lower fork service and /or and air can service. There have been reports of forks and shocks with too little/ too much oil inside.

    If the %sag is now reliable and you are still having problems with the shock, I recommend that you read the Bike Rumour article I sent you and start adjusting the air spring. There are an amazing number of devices you can buy to fit your shock that can adjust the positive and negative air chambers. These are a lot cheaper than a new shock.

    Ref changing the shock: I believe that you may be unhappy with the result. You keep referring to needing a stiffer lockout. I have had shocks with a lever that increases compression damping from Open, through Pedal, to Firm (ie "lockout"), I soon stopped using it except for long climbs up tarmac and even then I believe it was only a psychological boost (but I was having it anyway)!
  • danlightbulbdanlightbulb Posts: 660
    I always felt the shock was fine on the descents so never thought to look at the shock for climbing because it had the pedal mode, which I thought overrode the travel anyway.

    Alternatively I may have set up the shock right originally then its slowly lost a bit of pressure and Ive not noticed until recently when the bike felt draggy.

    It still feels fine on the descents with 50 more psi in so i dont think Im that sensitive to setup on the downhills but am more sensitive to it on the climbing.

    If i can feel my pedalling power being lost into the suspension then I dont know what else to do. Clearly the lockout is still allowing some travel - I guess Id just rather it didnt so the bike behaves like a hardtail and all my energy is transfered to motion.
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