Ok try the hotter plug and then tune it some more. If the top speed feels good to you at the current settings then work on leaning the LSN to get the idle just right. As you lean the LSN you will also have to start lowering the idle it's self. when you have the LSN just right you should be able to make a high speed pass and stop right in front of yourself and the idle should drop down to a nice stable idle pretty quickly. If it idles high for a few seconds then drops low your still to rich on the LSN. If it idles good for a second or two then drops super low and just dies you are also too rich on the LSN still.