I personally think that the front stock savage
brakes work amazingly well, granted, a bit on
the soft side but I see this as a poormans ABS
that lets you stay in control, till' you really pull.
Even when riding 2up, 700lb total (bike+gas+gear
+ 2 adults) it stops on a dime, the rear drum break
I rarely use but works also well; can't complain 1 bit.
Then again, look at the huge disc brake from my
200lb 125cc or the one from the 100mph ninja 250.
Yamaha sr125

Stock Ninja 250

Aftermarket double ninja 250R

Buell XB12 outside disc

Old-school ducati double drum brake

To change the ls650's front brake I think it's better (and cheaper)
to just get a different rim and forks, quite a few of them will fit.
Anyone out there has a brake/rim mod or a rear-disc savage?