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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/technicalities-spring-rate-and-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.
 

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Discussion Starter #23
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. *
 

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Discussion Starter #26
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.
 

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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...
 

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Discussion Starter #28
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.*
 

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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
 

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Discussion Starter #30
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. *
 

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At 180lbs, the stock springs should be fine for you. Best thing for you to do now is "tune your own". Grab your screwdriver, set everything to wide-open, go ride a section of bumpy twisty road for 10mins, stop, set everything to fully closed, repeat. Make a strong mental note of how the bike behaves differently. Then, set everything to 2-clicks from open, and 2 clicks from closed, repeat. That should give you an idea how extreme settings make the bike handle differently.

Using those three reference points, its now just a question of 1-2 clicks in either direction, which is best done out on a longer ride.
 

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At 180lbs, the stock springs should be fine for you. Best thing for you to do now is "tune your own". Grab your screwdriver,.
i was thinking the same thing.. thats pretty good weight for any sport-bike . Should be within adjustment range :D

but instead of flying blind for a few hundred kilometers I suggest you go look up your bike HERE op!!

this will get you going in the right direction and then you can make small adjustments one way or the
other.. if our calculations are correct you're likely within a few clicks.. Back in the day Sport Rider Magazine
would do yearly reviews of new model bikes and came up with a list of recommended starting points.

you are looking for a poised ride, one in which the chassis is not upset under normal riding
conditions, rear of bike balanced with front and vice versa.. front end dive is no fun.

https://www.cycleworld.com/sport-rider/suggested-sport-bike-motorcycle-suspension-settings/


Suggested Sport Bike Motorcycle Suspension Settings

Sport Rider's setup recommendations for every motorcycle tested from 1997
November 17, 2009

These tables show suggested suspension settings for each bike tested by the Sport Rider staff. Scroll down for your brand/model of bike. You can also use the tables to find which issues of Sport Rider each bike was tested. For more information about suspension setup, visit our Sportbike Suspension Guide, which has a setup guide, a suspension tuning guide, and links to various useful articles on the site.
 

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Discussion Starter #34 (Edited)
All good info, suggestions and observations.*

Here is what I'm at right now:

Front Preload: 3 lines showing Front Rebound: 1.50 turns out Front Compression: 1.25 turns out
Rear Preload: position 5 Rear Rebound: 1 turn out Rear Compression: 1.5 turns out

These were settings I 'stole' off the Internet. My old f4i is turns, no clicks.

I think I will take the time to play around with them some. Probably even take them to the extremes to see the differences. *

I'll definetly have a look at the cycleworld settings too.

And yes Chia I have no doubt that my suspension is pretty bagged out and in need of some serious servicing/repair. But I've got to work with what I've got right now. Had hoped to go through it last winter but life got in the way.

Thanks again for all the input. It's appreciated. *
 

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"Internet settings" are very rough at best and are based on a newish bike, not one that has 10's of thousands of kms on it and potentially in need of rebuild.....food for thought.
ahh yes i forget nobody does maintenance on forks.. ever :D

all i mean is literally, a starting point. I think its easy to forget when you 1st started playing with
suspension, you also didnt know how each setting affected another.

if you start with an informed 'setup' you will learn much quicker how far not to go in one direction or another..
you'd still start with a way more balanced ride than if going it alone i would think.


if all that fails, you could just service the stupid bike before you ride it :flip :canadian

:coffee
 

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Discussion Starter #39
Yah it needs to be gone through for certain. At this point I'm just happy with better than it was.*

Last winter was a super tumultuous time for my family and I. Planned a downsize/move and in the end did a complete 180. That my excuse and I'm sticking to it. Lol.*
*
 
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