Suspension tuning. - Page 2
Page 2 of 3 FirstFirst 1 2 3 LastLast
Results 16 to 30 of 42

Thread: Suspension tuning.

  1. #16
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    is the rear spring not progressive or variable rate? So preloading it should affect the stiffness, no?

    https://m.youtube.com/watch?v=3FeZJRiAXRkThis is the vid I was referring to. **https://m.youtube.com/watch?v=3FeZJRiAXRk
    *

    what he shows/refers to in the first handful plus of bikes is exactly how my bike is, no static sag. Beyond that I believe the adjusters for the valving are turned to hard as well, or slow as you would maybe call it? This combination seems like it is making for a stiff suspension and a rear that wants to unseat me. Before I buy new springs or valves it seems logical to me to reduce preload and adjust the existing valving to the softer settings?
    Last edited by Squisher; 10-22-2018 at 06:19 PM.

  2. Remove Advertisements
    BCSportBikes.com
    Advertisements
     

  3. #17
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    Quote Originally Posted by the bartender View Post
    Unless the valve is closed (which i mentioned above), all hydraulics is doing is managing speed/energy.
    So every suspension adjuster on my bike that is labelled soft to hard isn't making the suspension softer or harder?
    *

  4. #18
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    I can follow you that the preload affects the height but it also affects the sag no? *Which is directly related I believe to the stiffness? *So a buy product of decreasing preload/height is a increase in sag and essentially less stiffness of the suspension? *Having little to no rear sag is angling my bike forward I think and making the rear suspension act stiffer, no? *That's besides the inherent negative handling characteristics that that imbalance gives to I think? *Oversteer?
    *
    I'm not trying to be defensive, I'm just trying to learn. If I thought I could or did know it all from watching a couple of you tube vids I'd not have started this thread. *

  5. #19
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    I'm really trying to wrap my head around this preload thing. So when you preload a spring you don't make it stiffer but it then requires more force or weight to compress it further? *So right now with the rear of my bike adjusted up to no static sag I 'feel' the bike is stiffer because of the incorrect geometry, the shock travelling in a more limited range because of it being 'topped' out and the spring requiring more force or weight input to get it to travel fully, and my suspension having no or very little downward travel range to soak up road irregularities and for braking traction. Also reduced braking from the geometry angled forward if the front preload isn't as stiff?

    Is this somewhat on the right path of thought?*

    My brain hurts. Thank god ive got all winter to hopefully wrap my head around this. *Or If I can't atleast I'll know and have the time to pay someone who does before spring.*

  6. #20
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    I've read a few things now that say that preload doesn't affect stiffness. But this video would seem to imply that on a progressive rear spring preload does affect spring rate. That only on a linear spring would it not? And even then it still affects the stored energy of the spring, so while not technically stiffer preloading it still requires more force for further movement.

    https://m.youtube.com/watch?v=Bs0uEWmrrLQ*
    Last edited by Squisher; 10-22-2018 at 10:09 PM.

  7. #21
    Fastronaut Array Danke's Avatar
    Join Date
    Sep 2005
    Location
    Danger Zone!
    Bike
    RC
    https://motochassis.com/articles/springs-and-things/

    This guy is a great source for info on suspension.
    Fill the house with bees.

  8. #22
    Original Pirate Material Array TMR's Avatar
    Join Date
    Jan 2003
    Location
    Vancouver
    Bike
    Suzuki Burgman 250 Supersport
    Your stock spring is most likely linear rate. Increasing preload doesn't change the spring rate, however it does move the force required to initiate compression further up the linear curve. This is best envisioned with a graph: https://www.sportrider.com/technical...preload#page-2

    On the topic of preload and mentioned earlier, not only will changing preload affect the force needed to initiate spring compression, but depending on how much preload you setup, can change the character and balance of the bike. This is affected by either changing rake (increased rear preload, rear end is elevated relative to front, trail is decreased), and concomitantly, droop travel will be affected as well. By how I've read it, it seems like you have too much preload in the back at the moment and so if I were in your position, I would back preload out a few turns. You want your bike to have both static sag and loaded sag; for the street, I would run 1/4 to 1/3 of my absolute suspension travel as loaded sag, deferring to more sag if you're riding rougher roads.

    Note that as you change sag, you should also be changing your dampening adjustments as well, especially rebound. If I were in your position, I would do as suggested previously and back out rear preload and ideally have it adjusted with proper front/rear static and loaded sag, and then run the bike with all clickers fully out (soft). Then run your normal roads and slowly increase the dampening until you achieve something that is favorable; I personally shoot to have the bike as soft as possible for street riding while minimizing front/back oscillations. Obviously this will change depending on surface conditions and the pace at which you ride. Hope that helps a bit.
    Last edited by TMR; 10-23-2018 at 10:37 AM.

  9. #23
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    All of this helps. I just need some time now to start messing with it all.*

    I've got a board in my shop I'm going to record all the settings I've started with and then start adjusting/recording my changes.

    If in the end I can't get the bike to a decent place myself I'll look for professional help. *and if it comes to that point hopefully I'll have a basic enough understanding to know what they're going to do for me. *

  10. #24
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    Quote Originally Posted by TMR View Post
    All great advice here. Another invaluable resource is the Dave Moss Tuning videos: https://www.youtube.com/user/CatalystReactionSBW

    Guy is a wizard for setting up bikes, you'll learn a lot from his videos. The paid content is well worth it.
    I've got his 'app' now. Really eating it up! *Great stuff.*

  11. #25
    Registered User Array the bartender's Avatar
    Join Date
    May 2011
    Location
    vancouver
    Bike
    2014 Aprilia Tuono V4R
    Quote Originally Posted by Squisher View Post
    is the rear spring not progressive or variable rate?
    Almost always linear. most that are labeled progressive, are not.

    TMR has posted lots of great info below too.

  12. #26
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    Yes thanks to everyone who chimes in. I believe my rear spring is linear, the first two coils are kind of closer but all the rest look evenly spaced and the diameter of the spring doesn't appear to change.*

    I've been stocking my shop with firewood most of the day and trying to motivate myself to repair the exhaust on my truck. *Ive taken a few moments here and there to have a quick look at the bike but the honeydew list is to long right now to dive into it seriously. Winter is coming fast.

  13. #27
    Static sag is the weight of the bike reflected on an unloaded spring. There should be range of movement (setting) available somewhere. If you get no static sag on an un-preloaded spring your spring is too stiff.
    No static sag via cranked up preload, means there is stored energy in the spring as it returns to length with more force than the bike weighs ... the catapult. PO had bags on it?
    Rider sag is the bike and rider with gear, there should be a range of movement (setting) available somewhere...
    Rider sag can be adjusted to affect the steering, less sag/quicker steering, more sag/slower steering.

    Try backing off the preload, see if you can get the static sag, then go for the rider sag ... at least you'll find out if the spring is correct (probably good enough)
    The damping is just controlling the speed of the spring movement.
    Take the spring off the shock, compress the shock and see if it returns to full extended length, if not, it's probably lost it's gas charge...
    Last edited by knotasportbike; 10-23-2018 at 09:14 PM.

  14. #28
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    To update this. And again thanks everyone for trying to edumacate me and help me out.*

    I learned how to adjust my basic suspension settings. Both my front and rear preloads were maxed out(rear might have been one notch from max, fronts were buried) when I got the bike and backing both of those off/out solved most all of my issues. I'm sure there's plenty of fine tuning that could be done. But in the end I found some old info on a cbr forum where a guy close to my weight on stock suspension posted up his settings and that's what I moved mine to and have just left them there for now. Reset the compression and rebound as well as the fronts weren't adjusted evenly, all over the map.

    No launching out of the seat on bumps. And the suspension 'feels' good to me.*

  15. #29
    Registered User Array bacchus40's Avatar
    Join Date
    Apr 2006
    Location
    two feet off the ground..
    Bike
    MIAMI 998 YZFR1 '09 & RAIDER S XV19CSEL '14
    i was half way thru reading your post as i started to respond. yes its common for folks to max out their
    pre-load instead of getting the correct spring rate for their particular application. I dont know if its a young
    cbr thing but i've heard it most from cbr600 guys. i never owned one so i dont know either way
    http://bcusedoil.com/

    Quote Originally Posted by Land Roving
    Life is too short to own ugly motorcycles.

  16. #30
    Registered User Array
    Join Date
    Jul 2017
    Location
    Coldstream, BC
    Bike
    Ninja 300/CBR f4i
    Interesting. Backing things off some seems to have helped a lot for me. And I'm not light about 180pds. I'm not ripping this thing on a track either though, although I do enjoy some spirited road riding. I have no doubts I couldn't still benefit greatly from a tuned suspension and springs of the proper rate specifically for me.*

    For now though I'm much happier with it than I was. *

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •