Bicycle Mechanics - front brake shudder

i've got a surly lht with a suntour xc pro front brake and kool stop salmon pads. when i brake with anything more than the gentlest pressure i get a crazy amount of shuddering. so much so i can see the rack move back and forth about an inch.

is there anything i can do to cure this, or am i gonna have to buy some stiffer forks?

An out-of-true front wheel can cause shuddering. Have you checked it?

Also make sure that your brake caliper is centered. Look to make sure that the pads are contacting the rim at the same time, or just look down on the wheel while stationary, apply the brake and see if the wheel deflects in either direction.

everything is in order. it's almost like the brake is too powerful for the fork?!

the other thing that i wondered is whether the front rack could be causing the problem - as it mounts to the eyelets and the lowrider bosses. could it be reinforcing the bottom half of the fork through triangulation>? i guess i'll have to take it off and see

Check the headset next.

While stationary, straddle the top tube and apply the front brake. Rock the bike forward and back. If you can rock it, your headset needs tightening. If there's no play, then we'll move on.

I have the same issue with my Waterford. It has a 531 lugged fork and cantis and Kool Stop red pads. It only happens at slow speeds, probably the same for you. To verify, look down at the fork blades as you are shuddering. Mine move a lot; it is easy to see. I did improve the situation a little with less grippy pads. I've learned to not use the front brakes as strongly as the rear and all is well.