I'm replacing my hand grips and on the throttle side I'm having a slight problem. I putting on the Black diamond grips on my 2010 FXDWG. When I twist the throttle a bump when I first start twisting but then its fine all the way to WOT. There is also a bump when twisting back right before you hit idle. It's almost like it's catching on something inside the housing. Does anyone have any ideas on what this could be. I've took it off and put it back on a couple times. It's starting to aggravate me.