I take my chain off when I clean the drive train. If you have a quick link on it, it makes it really easy. I use simple green to clean the chain and then re-lube. if the drive train is really dirty i will use a tooth brush with some simple green.. scrub, rinse and then dry. I usually just wipe off the deraileurs with a rag... Lube your chain when it starts to make noise... dont use WD-40, try to find a lube that dries after being applied to prevent excess gunk buildup like GT-85. There are many out there.