Tyre's mystery line

I have about 400 miles on the Bridgestone BT023R on the front wheel of my 2005 Honda CBF600N and I’ve noticed a strange line just left of centre that runs the circumference of the tyre. Has anyone else seen this? Is it a concern?
Zoogie, MCN forums

It’s nothing to worry about. The increasing amounts of silica used in tyre rubber compounds has a tendency to build up quite a static charge as they spin along, so that line is an ‘earthing strip’ to discharge any current that builds up. It will be there for the life of the tyre, but it isn’t a wear indicator, those are at the bottom of selected tread grooves.