anyone ever run time trial, or "bullhorn" type handlebars on their singlespeed mountain bike? i've got a monocog, but its used mainly for city riding/commuting/delivery work, formatted with skinny tires and all that stuff. thing is, i feel like my bars are too wide and cause an obstruction. i'm looking into either a short riser or flat bar or bullhorn bars. my questions are, which ones in these categories do you recommend, and if i do switch over, is maneuverability sacrificed?