Originally Posted by 08Bonnie
Have you checked static sag in the front? Should be around 20-25mm. This is the distance your front forks compress with ONLY the weight of the bike. What about rider sag? Should be around 30-35mm. This is the distance the forks compress with the weight of you on the bike. I think this should be your first step.
I had the same issues you describe. My sag #'s were all over the place, after applying some tested theories the ride could not be better.
08 Bonnie - I have not. I do have the Thruxton preload adjusters installed on the forks, so with some luck, unloaded and loaded sag MIGHT fall in the range of the preload adjusters.
I did notice this am after filling gas tank to the top, the additional load on the front end seemed to stabilize things. So, next step was to play with the rear shock preload. The Progressive 440s make this easy, with their hand-adjustable rings. First I noted that I was set very low on preload (one hash mark from no preload at all, which equaled 25 (lets call them clicks - actually visible marks, easily counted). Cranked them in to no preload, worked my way back to 25, then to 50, finally 60. This seems to have eliminated more of the flutter. I believe this would have slightly increased (a) front end loading and (b) reduced front end rake.
GBNF: 03 T100 Luc Org and Silv: 122/42 jets, TORs, 18T, UNI filter, no AI, Polaris bellmouth, Metz 880 tires, Prog. 440 shocks (105/150 springs), 11-1124 frk springs, Thrux frk caps, gaiters, MotoTwin bars, 6024 lamp, htd grips, 12v outlet.