Went for a spin on my cali 98ev yesterday It seemed down on power. Imagination? no misfires, easy start, smooth idle is it me or she. Any ideas? brakes not binding.
how long since you last rode it ?
perhaps the fuel is going off
Or have you been riding something modern ! 
A like and a funny button needed.
Best way to check for sure is to do a top speed run.
If you can get say 115-120 mph on the clock it is probably not down on power!
If you are still not convinced Black Dragon in Somerset will put a supercharger on it for you.
Might be worth cleaning or replacing air filter(s) and dropping a new pair of plugs in, these things can creep up on you.
fresh fuel, clean K&N, haven’t been disloyal to her. Will try plugs
My Ural felt like this this morning. But by this afternoon it felt ‘normal’. I think it was just me being impatient. Plus Welsh hills probably not helping.
Blue feels like a complete slug if I head out on that after a period of riding other bikes - to the extent that I’ve wondered if it was only running on one as I tootled off down my road. A few miles later we’re both back in the groove.