Usually my approach to forks is to overhaul them first. Mostly I stick to 10W oil and the stock air chamber. Then I turn the damping to fully closed, compression damping closed, rebound closed. I turn out the spring pre-loader. Now strongly press down on the fork, it will see-saw. Turn in the spring pre-load until it stops doing that, that is about the right setting. Usually I can leave the compression damping fully closed, maybe half a turn open otherwise the fork will be too soft and it will bottom out under heavy breaking. I set the rebound damping to a setting that makes the fork go from compressed back to it's origin in about one second.
Then I put a tie-wrap on one leg's inner tube and take it for a ride, doing everything I normally do and some things people would call 'stupid' like braking hard on a road that has many heavy bumps. After all that the tie-wrap should be *just* touching the bottom of the fork (in the case of an upside-down fork). So if you would ever go through a pothole while the bike happens to be on just the front wheel the fork won't bottom out (hopefully). I adjust the spring pre-load depending on where the tie-wrap is until I get it where I want it to be.
The compression fine tuning is a matter of taste. Kind of difficult to determine what to do with it in the beginning. To get a feeling for it I'd try the extremes of both the front and rear rebound and compression dampings. Just turn it all the way in, go out and ride, turn it all the way out, ride again, do it halfway, ride again and so on until it's clear which setting does what. Then adjust bit by bit and test ride on the same road under the same conditions, especially note the tire temerature.
And then some... suspension is a bit weird and can get you frustrated. It's always good to write down a basic setting that you know will work for you with your bike and your current tires. Otherwise you'll be chasing your tail.
Back to the springs, before I replaced the B4's fork for a GSXR one I replaced the stock springs with progressive springs. It made the fork much harder and the damping characteristics changed a lot. I did go from 10W oil to 5W though, so I can't really say what the springs would do on their own, if I had stuck with the 10W.
Doesn't have anything to do with old men in my opinion, it's just one of the few things one can do to set up a fork that doesn't have damping adjustmens on the outside.
Topic: Progressive spring benefits? (Read 5760 times)