spring preload recomendation

Discussion in 'Parallel Universe' started by TowPro, Nov 11, 2012.

  1. TowPro

    TowPro Single Track Geezer

    Aug 21, 2009
    Compass PA
    stock rear spring adjustment.

    My manual says to run the rear spring at all the way CCW for 187 lbs.
    What about 240-250 lbs (with gear)? i know to add some for passanger, luggage, etc.

    My problem is I had it set where I like it, then I turned it up when my Nephew rides it and forgot to turn it back down.
    then I turned it up again (more) when my wife was on the back for a trip, then forgot to turn it back down. Then I think I added 5 more turns the last trip with my wife, and forgot to turn it back down. you get the idea. this could also be the reason I am always sliding forward in the seat.

    Anyway, rode it in the dark Saturday night and the high beam was as low as the low beam should be.

    I saw the link for the F800 ST configurator http://www.uthd.com/jeremy/f800st_config.html that shows suspension setting, and for 187 it says 12 clicks, so this is telling me the F800ST has a different suspension then the GS
    and anything over 450 lbs says "overloaded" but my manual says max payload 520 lbs.
  2. sorebutt

    sorebutt Long timer

    Jun 26, 2008
    The setting is really subjective. There are formulas for sag, but those are generally for competition or those that ride hard. People will tell you that it has to be set a certain way, but it is all based on how you ride, the roads, and load. Not what someone else uses for the settings. Ride easy on rough roads and you want it softer than riding hard on smooth roads. You need it a little stiffer with a load. I would keep it a little on the stiff side with your weight. Too much sag and the bike won't handle well, but unless you are riding hard you won't notice it.

    You shouldn't slide ahead in the seat if the suspension is too soft. It is probably because of your passenger pushing you ahead. Too soft and the rear should be lower so you would have to be sliding up hill.

    Just find out what seems to work well for your riding style. Too much sag and the front end will want to go straight in corners. Plus you will bottom out on big bumps. Too stiff is better than too soft, but the ride will not be as smooth, especially on rough roads.

    Write down your settings so you will know what changes do for you. After a while you will figure out where to make the settings for the condition. Or you can just set it for what someone on the internet tells you.:cry
  3. machinebuilder

    machinebuilder Long timer

    Jun 6, 2008
    East Tennessee
    for rear preload, it should be set so that you are at 1/3 the suspension travel with the load. this should put the bike geometry's at the design point.

    If you set it too soft there is greater potential to get headshake, :eek1 because the fork angle is too low.

    it also is not exact, I don't reset mine every time I change what I am carryiing.
  4. ADVSearcher

    ADVSearcher Been here awhile

    Nov 19, 2010
    Örebro, Sweden
    Read this thumb rule here on Advrider some were but can't find it now ...

    Start with the recomendation from the manual, then you know were you are and for how many kilos it's adjusted.
    Then preload 3 full turns on the knob for every extra 10 kilos ...

    It's worked for me, can notice that by having the same distance to the ground with my feets (toing a tiny bit) under
    different loads. And don't forget all extra equipment such as pannierholders & other stuff, all together they build weight.

    Good luck ...

  5. MikeMike

    MikeMike Long timer

    Feb 28, 2009
    Make absolutely sure your tire pressure is correct.
    You will know you have the spring pre-load correct when you are decelerating from around 100kmh to 60kmh, through that range or a little lower, and you take your hands a little off the bars and you get absolutely no head shake from the front end. It will oscillate side to side if you have it wrong.
    By the way, it usually takes a little more than you think you need.