Thanks for reply, going back perhaps, 40 years to when I had a Yamaha dt125 and a Suzuki x7. They both struggled to start if you had the light on. Turn it off and they'd start. I would prefer, to turn the light on myself. I've started it a few times since fitting the relay and it starts easily. Time I guess will tell if either of my batteries are on the way out. I would take them to be tested, there's a place in my town which would do this. But working a lot just lately so haven't had time. but I agree with everything people have said. Thanks for the replies.