There you go,
I watched the middle earth on the telly, The boys were on top of a mountain in minus temps, they warmed up in the camera van but they left the bikes on tickover for some time while they warmed up, It didn't show it but one of them turned the bikes off.. When they went to start up the bikes again both bikes had flat batterys.... So that's why I asked..
Tickover with lights on, maybe heated grips turned on aswell....
Cheers for all the replies guys, tosh