Sev

Preload has nothing to do with how stiff the suspension is. It controls where in the stroke the bike sits "at rest". Which is to say, set correctly, the bike should be sitting with the suspension compressed by about 1/3rd of the total travel. This is correctly adjusted preload. Adjusting the preload to "make the bike softer" means you're way too likely to top out the suspension as it unloads. Adjusting the preload to stiffen the bike makes it more likely that the suspension will bottom out. You cannot change a springs stiffness by adjusting the preload.

At 130lbs you have the wrong spring in there, you need to replace your fork and shock springs with a lower spring rate in order to get the correct preload for your bike.

Having said that... turning the compression out 3/4 of the way means you've given up almost all of your damping. The shock and forks are both going to collapse under you like a dented tin can. But then again if you have the spring almost completely unloaded you'll likely need it to dive like crazy in order to not top out when you return to stock.

This is going to contribute to your "front end coming up" problem, because the suspension is collapsing under you rapidly and bottoming out which then means the front has to go somewhere.

Dropping the front end sharpens the steering because it tightens up the steering angle and reduces the rake. Both of which decrease straight line stability and will improve turn in. Only an issue if you can't handle yourself down the straight. A 5mm drop isn't THAT impressive.

Besides that/one step beyond the vast majority of bikes don't have their forks flush with the upper triple.

Finally, your bike should be stable enough stock to not require the use of a steering damper. The old school ZX6R's were awfully stable regardless.

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Of course I'm generalizing from a single example here, but everyone does that. At least I do.

zvenkruspe

Thanks Sev for the details

My bike is set up pretty stiff for street riding. When I mentioned my compression on the rear shock I wanted to point out I had to stiffen mine quite a bit to get it more balanced and stop it from bottoming/topping out. Whenever I was accelerating out of a long even turn (almost 270º) and hit the bumps close to corner exit, my bike was moving around quite a bit cuz my rear was compressing too much.


I just wanted to point out to him that going back to stock height might give back more travel in the shock.

Sev

Shock travel remains the same if you replace the dogbones.

If you are having issues with both bottoming out and topping out then you have the wrong spring. Adjusting compression controls how fast the shock is allowed the squish. Adjusting rebound controls how fast the shock is allowed to unsquish after the bump. Turning the compression adjuster OUT reduces the amount of compression damping, meaning the shock compresses FASTER. This means you're more likely to bottom out with the wrong spring, and the back end will squat like crazy when you either get on it, or when you hit a bump.

Basically you're turning knobs to correct having the wrong spring in there. Your bike is not "set up stiff". Your bike is set up incorrectly for you.

Also, accelerating out of a 270 or a 90 doesn't make a difference to your suspension. It cannot see how you're turning.

__________________
Of course I'm generalizing from a single example here, but everyone does that. At least I do.