i know that the black wire off of the engine needs to be earthed to the frame, just in case u connected it up to the battery or something lool
there isnt a black wire off the engine on an SR. right, on the left side of the chassis behind the left hand side pod insert thing there should be 3 wires that bolt to earth, one fro battery one from starter and god knows what the other is. that is your main earth point on the bike.
but im earthing it all on a speedy frame imp: whats the deal with that random black wire it goes no where and the starter earth is on the frame and the coil is aswell