Stalled again today while bike (GT) was idling at stoplight. Attempted usual restart except on this occasion the restart was very abnormal, behaving as if battery voltage was very low. Engine very slow to turn over but after two attempts it started and I continued to work. Straightaway I checked battery cables upon arrival all good. Bike restarts as normal now. Fuel tank 3/4 full, 91 octane, air temp 77F, bike was stopped, in gear, clutch in at red light light when it shut down. When attempting restart the starter turned over very slowly and the dash lights etc. dimmed almost completely until it restarted finally. Any thoughts? Mileage is 1400 ish miles