providing you have not let the pads get so low that they have worn through the friction material and the metal part of the pad and then the piston has started to wear away on the disc (which i have seen)then there should be no reason to have to bleed the brake,does the brake still have a good feel to it(non spongy)if so then just put your new pads in.take the three wheel bolts out move the wheel over slightly then undo the two 13mm headed bolts ,put a big flat headed screwdriver between your worn out pads and twist it to push the pistons back in watch them to make sure they do not tilt and jam as they are only short pistons, then pull out your two springy pad pins and the pads will fall out put in your new ones the part number is FA115 and then simply put them back together and refit them.as rayb says theres a window in the master cylinder have alook at it with the top of the master cylinder level and see if it has plenty of fluid in it the top and bottom of the sightglass is the high and low fluid level indicator.
adam bike doctor
December 2009