well yesterday, my battery died in the F4i, so i hooked it up to my charger at the recomended voltage and time. it called for a quick charge on the battery of 2v at 1 hr. so i did that and took off, no problems. well this morning, i went to school, then after school went to work. when i get to work, i notice a lot of white residue on my swing arm and tire and rear breaks. turns out the battery was leaking acid all in the box that it resides in, which was in turn leaking out a vent hole in the middle of the box. called and ordered a new battery as soon as i saw this. anyone know how to remove the stains left by the acid? when i was riding home after work (i had to push start the bike) it started raining pretty hard and seemed to wash some of the residue away, except for on the lower part of the exhaust where it kinda melted on there. a couple of other things too. are k&n air filters really worth the $50 or should i stick with the OEM filter. also what is the best replacement spark plugs for the F4i. my bike feels a bit sluggish lately and im thinking its either the plugs or air filter. bike has 20,300 miles on it and still running like a champ, except for the dead battery. thanks in advance guys.

 

its called soft scrub should do the trick

 

Or you could put coke on it too. You'll have to rinse that off too though right after.
As for the air filter, I went with a K&N but only because it's reusable. zero performance gains. For spark plugs, just stick with oem ones, I think they're NGK's.