I spray a bit of WD40 on a rag and give the chain a wipe when it starts to get grubby. Ideally you shouldn't let the chain get so nasty that it needs a proper de-greasing. If it gets that bad I would replace the chain.
I learned a lesson of not maintaining a chain a few years ago.................went for a ride on Boxing day on my beloved YZF750 then put it back in the shed a waited for the snow to clear. Several weeks later on a ride to work the chain snapped at 85mph.........i ignored the fact that there were obvious tight spots, the chain was bone dry and some of the links were decidedly rusty.
I was lucky cos the broken chain flew up and ripped the arse end of my bike off rather than wrap itself around my leg or the back wheel
