Join Date: Aug 2005
Location: Orangeville, Ontario, Canada
Going backwards it could be dirt, rust, loose connections, worn starter, brushes at their limit, loose connection internal of the starter motor, corrosion on any or all high powered wires, corrosion on any or all control components and wires, poor contact on the handle bar switch, relay is loose, dirty, burned, corroded. Then on the other side that is the grounded side, repeat the above. Especially the motor negative lead side is failing or failed.
Try starting the bike from an external source, a jumper and if it goes then your problem is anything leading to the starter motor. Isolate any and all probable things in that power circuit.
Also could be that the starter is doing its job, but the job now is over rated because of binding, gobs of grease, worn parts.
You need to isolate the electrical from the mechanical. EG switch kill to no run and see if it attempts a start. Compression too high, binding.....