Try using a nail brush and kitchen/oven spray. It always works very well.

 

I used magic eracer pads and wesley's bleche white, it works perfect, I used on both of my bikes,on the heritage I got the thunder header 2unto 1 and after a couple of months my rear tire turns yellowish,and the pads and the wesley's brigns it back to the original white.
just my two!!!!!

 

SOS pads.