Changing my own front fork springs

Increasing the compression damping should minimise that.
If the forks are bottoming out, you might want some more preload too.
As you say, I would change settings first, then think about changing springs.

 

I would measure the unloaded, static & rider sag to see if the current springs are suitable. What rider sag are you looking for - 30mm? I guess it depends if you will be using it more on track or road. Adding more oil has a similar effect to upping the spring rate; whereas using heavier oil will increase damping (I think).

If you are in the weight range of Joe Average, you should be able to dial the fronts in quite well.

Do you use a tiewrap on your fork legs; are you using all the available travel?

 

I found this a good read Matt

http://www.moto-racing.co.uk/Guides/motorcycleSuspensionSetup.htm

 

First things first, suspension evaluation of Fireblade...

 

Start with this one for sag...
At the latter half of that vid he talks about the damping settings...
The very end shows you how to check that they are balanced front to rear.

 

After that, compression is a bit more subjective... Use zip ties on forks to check for maximum movement... and increase damping to reduce front fork dive under braking...


This video givese alot of information on the bike bounce check...


Just remember when setting rebound damping that hard damping reduces the ability of the spring to rebound, therefore it makes the "feel" of it softer. With very soft rebound damping, the springs return after a bounce VERY hard, and with hard rebound damping, the springs return after a bounce more slowly, because the DAMPING of the rebound if high.

I would say just look at alot of Dave Moss videos...


Good Luck, record everything first, set it up as in the videos, record those settings. Then make changes to one thing at a time to really suss out the differences that the changes make...

 

Yup, a very good read. I have this saved as reference...

 

Remal - have you used the spring rate calculator here Page
Once you put the usual stuff in about what bike and your weight it tells what the stock spring rate is and what spring rate you should be using. If you are miles away from the stock spring at least you know what you really need to correct the problem. It's not a good idea increasing the preload too much. With the correct spring fitted you need very little preload.
After spying you at Elan Valley last year I think you may need a stronger spring - please don't take that the wrong way. I'm at the other end of the scale needing a softer spring.
Also I know some of the better front fork cartridges have the facility to change the spings very quickly with the forks in situ - WSBK stuff.

Steve

 

I also meant to add; if you do need heavier springs, you should go for linear instead of progressive. Progressive are great in bikes without damping adjustment; I have in fact fitted them to my Triumph Thruxton.

I agree that changing preload so that it's outside the sag range is not recommended; the correct spring should hardly need any preload.

Interesting stuff eh.

 

If you are near my weight 16st then the standard springs are spot on.

Also like Swiss T has just said linear springs are better. I've just fitted progressive springs to the SP1, and although they are far superior to the standard springs that were fitted, linear springs are far better suited to our bikes as they have damping control.

I'll be changing the springs out on the SP1 directly.