I had one for 3 years...It's a good bike...For some reason alot of people think that they have huge torque but the inline 4's have much more..However, then engine is smooth, relatively fast and has a powerband that kicks in at about 7,000 rpm and barely feels like it's working when you're going fast..Kind of top heavy powerband considering it's a Vtwin...All of the inline 4's will smoke it with EASE...Twist the throttle to the stop anywhere under 6,000 rpm and not much seems to happen...But for a vtwin it is a fast one and if you're not expecting too much it's smooth and fun to ride...It has a really cool winding sound from the gear driven cams and the engine doesn't make any weird noises...
IMHO, the RC51 would be a good streetbike if it wasn't so uncomfortable..1 hour and you're rear is numb and your wrists and neck are cramping and while it's fun to ride it's hard to enjoy it when all you can think about is how much your neck and wrists are killing you...An aftermarket seat and bars are a must on this bike if you want at least some form of comfort.
Great looking bike and it's rare.
Smooth, cool sounding engine.
Very stable at speed and planted in the turns.
Very solid quality feeling to the bike.
Ease of maintenance...Oil changes(remove both fairings) Plus if you need to add a little oil fairing has to come off, air filter(almost impossible to install), and spark plugs are WAY more difficult than they should be.
It feels kind of slow until you get to 7k
Slow turn in