Yamaha did not release the HP numbers, but being a low rpm air cooled twin, it probably has around 75 ponies. Divide that by its hefty 950 curb weight (I don't think that is wet weight, either) and you get a power to weight ratio of about 13.0 hp/lb....pretty similar to my wife's V6 Kia Sorento.

F6B is about 7.5-8.0 hp/lb, depending upon whether power at the wheel or the engine's output itself.