Fairy dishwashing liquid. Does a decent job with dishes coated and caked in cooking oil, so I had to see it's full value with motor oil, grime, and grease. Surprisingly, from a short stint playing with the bike, one wash and that about done it. Go figure... may be a worthy tip. Laundry powder's next
I use this solvent-less industrial hand cleaner by dominant called "remove-all". Great stuff. Can't seem to find it on their website though... hope they still make it!
Septone Orange scrub, very good abrasive hand cleaner, dad would buy it in bulk when he was a diesel fitter.
i use repco hand washer, just a generic white bottle, no water required and will remove everything off your hand, and its cheap.