[tarochan]

the front ''hissing'' is normal.the rear is likely dirt and dust,blow the rear caliper out and or pull the pads to clean them.lots of options for the rear cowl,from a seat cowl to full rear cowl to the mono cowl with subframe ,search and you should find something to fit your budget.

Just so...I've got a 749R and the fronts hiss and I've ridden 999S, same deal. Squealing rear is usually dust, same as clutch squeal.