Today I got the R out and rode it for about 30 minutes, pretty hard as usual, but when I got home and shut it off it was making a hissing noise. It sounded like air leaking form a tire but it was coming from the top of the engine or maybe the radiator. I checked the radiator hose for a break or leak but found none. Any input would be appreciated. Thanks in advance

 

are you riding in snow? snow+hot engine=steam sound.

 

Nope all of the snow has melted here. It sounded different than water hitting the engine, sounded more like pressure or air leaking.

 

in that case then, I'm clueless

 

Pull off your front plastic and check your water level.If its low then you have steam or hot water leaking somewhere.If if its not low then ride it with the plastic off so that you can isolate the problem.