hm....

rotate.js

var e = this.velocity
                      , t = Date.now()
                      , n = t - this.lastFrame;
                    this.lastFrame = t,
                    e *= n / 16,
                    this.rotation = this.rotation + e;
                    var r = "rotate(" + this.rotation + "deg)";
                    this.$el.css({
                        "-webkit-transform": r,
                        "-moz-transform": r,
                        transform: r
                    }),
                    this._requestAnimation = window.requestAnimationFrame(this._update.bind(this))