It's on the trike I recently bought, while idling in neutral I hear a growling sound from inside the motor. It goes away when I pull in the clutch handle. I've also noticed shifting is also rather sloppy but may be due to the system needing a good flushing. Re. the noise, am I possibly looking at a new clutch in the near future?
I've had very similar sound on my Blue / Cream standard since around 2003 when I got it, goes away when clutch is pulled in just like yours. But I thought it was just normal. It wasn't until this September I picked up another Valkyrie (Project) and once I got it running found it doesn't have that same growl or whirring at idle. It also shifts a little smoother and feels a little more agile, a little more rigid underneath me. Since it's been so many years with the growl I guess that's not a major concern for me but I will be looking into why old blue is a little more sluggish feeling underneath me.