So I bought a 2009 1300 GT about a week and a half ago. The bikes been a lot of fun and I've had some good times with it already racking up bout 1000 miles. Earlier today I was on my way back into town and got down to about 30 miles left on the gauge so I decided to fill up. I stopped at a new gas station and filled up with their premium. It's a 91 octane with 10% ethanol. This may be a stupid conclusion but within roughly 10-15 minutes of filling up I noticed a tapping noise as I came to stop lights at idle. Upon further inspections it seems to be coming from near the top of the engine near on the left side if you're seated on the bike. I can't help but feel that these two events may be related, any info / thoughts are much appreciated!