I looked back 200 threads in this section and didn't find much on this, and my searches didn't reveal something that might yield an answer...
I started the front brake improvement process on my '06 by switching to a stainless brake line. 18 ft-lb on the banjo bolts. Honestly, didn't notice much difference. Put some time on that.
Got the EBC 320 semi-float rotor, used the OEM caliper with the EBC adapter and kept the OEM Master Cylinder. That was a big improvement. Enough for some. Blue Loctite and 16.5 ft-lb on the hub bolts. The mounting bolts that came with the EBC kit were obscenely long and I had to cut them down to lie flush with the back of the bracket. Put some time on that set-up.
Looking for further improvement, got the Eagle Mike stainless steel adapter for an SV650 caliper (*****
& came with SS stand-off washers to compensate for the shoulders on the SV bracket, and SV bracket mounting cap bolts — drilled the caliper carrier threads out with a 25/64th bit for thread removal to create clearance for the cap bolts), and installed that. 17.5 ft-lb on the mounting bolts. I didn't have to grind down the allen/cap bolts that came with the EM adapter as they cleared the stainless drive buttons with only the chamfer showing through, although EM also shipped shim washers for under the bolt heads as well--for now, I'm letting the bolt nubs (chamfer) hang out (but I'll carry the washers around for awhile.)
Back together, bad weather, no test yet, but one concern...
The SV650 caliper has a greater fluid capacity when compared to the KLR650 OEM caliper. The initial bleed went well, I think, and I tied down the lever to the hand grip over night to squeeze any bubbles. While the brake pads come to lock using the OEM master cylinder, that happens a hair short of the hand grip (not enough room for a finger.) Pads start significant gripping with the brake lever is only 1/2 inch from the throttle cable housing and at full grip, the lever touches the throttle cable housing. This is not confidence inspiring or comfortable. I'm looking for a 1 inch pull on the brake lever and not a 2.5" pull from start to maximum hand pressure and no sudden lock up.
Barkbusters on the handle bars.
I may try removing the caliper and rotating until the banjo bolt is up to see if I can find air— though the position of the bleed screw should obviate that. Hmmm—I did this alone, and it could have sucked air—I'll bleed again. The feel isn't "spongy" that I can tell, but the lever travel is too long. While the dime mod is my next step, I don't want to introduce drag and I'm wondering if there is a better master cylinder to install.
I'm thinking I would need more volume with less travel but don't want to reduce pressure at the caliper nor create a "wooden" feel.
Troubleshooting or Master Cylinder suggestions?