I have just bought an 08 with 2000 miles.....have been reading threads about synthetics....still confused...what viscosity should be used? i live in Ontario Can which has temps all over the map last week 70 deg this week 40's.....yamah sells semi synth.and afull synth.....have always used yamalube 20w40/50 in 04 vstar for 76000 kms no problems .....so with this its a decision after this has been broken in...I have a friend with 92 goldwing he uses shell diesel oil from wallyworld....
any thoughts please