| Hmm,two places to check,the first and most obvious one is the relay by the battery.It will be a little black Siemens item that costs around £4.Just about every Duke has one fitted somewhere.They are pretty cheap and nasty.Usually fail when exposed to exessive heat or vibration.
They fit them to Monsters under the tank as a sidestand cut out.Ive replaced two on the missus bike and keep a spare under the seat.
The second place to check is the temperature switch.Its usually sited in the plumbing on the side of the front cylinder.Not heard of these failing tho. | 
Linear Mode
