I just had the 10K mile service done on my 2012 Harley FLHX Street Glide with the 103 engine. I changed out the oil to AMSOIL 20W-50 V-Twin at 7K miles this past spring prior to my trip to Laconia Bike week in June. During the last 400 miles on this 3K mile run on this oil i had noticed that my engine was making more noise than usual during a cold start in the morning. The HD tech notified me of this also which had confirmed that is was not my imagination. I will say that the oil was run all summer with hi heat temps all summer long & had endured much stop & go high heat traffic conditions. I had the HD tech change out the Amsoil to new HD Syn-3 oil & the engine is now quiet as a church mouse on a cold start & during operation. My conclusion based on this is that the Amsoil syn oil sheared & weakened during this interval. I thought I was paying a premium for this oil so that this type of stuff would not happen? Amsoil you have lost me as a customer!