Everyone has their favourite products so there is no definitive answer, just do it regularly - every second tank of fuel is about right unless you ride a lot in shitty conditions, rain, dirt roads etc. Heres what i do and my chains last. Go for a ride so the chain is nice and warm. Put the bike on a rear stand so you can spin the wheel. Spray WD40 onto a clean bit if rag and wipe the chain on the outside, while rotating the wheel until all the old cruddy goo is off - the rear sprocket area is a good place to do this. You'll need to spray and use a clean bit of the rag a few times. Then do the inside of the chain the same way. DON'T spray the WD directly on the chain and spray away from the bike as you don't want it getting on your brake rotors, plus the carrier in the WD may get into the chain o rings and leach out all the good lube in there. Once the chain is clean spray a good lubricant onto the inside (ie sprocket contact side) of the chain while you rotate the wheel until it is evenly coated but not dripping off. Leave overnight to dry before riding. I like Belray as it doesn't spray off all over my shiny bike.
Sent from my iPhone using Motorcycle.com App