Hmm... let me go look up my file and see if I can sort out some of the steps.
I did my bright outline layer, and then ran a digital camera noise removal over that. I separated the background from the biker. I made several duplicates of the bright outlines, both of the backgrounds and the biker.
On the background version of the bright outline, one set of motion blur is horizontal to emphasize the speed of the bike. Another is diagonal for the rain.
Top, bright outline of biker, set to multiply.
Next, bright outline of biker, set to burn.
Next, bright outline of biker, set to normal.
Next down, bright outline of background, blur horizontal, blend mode multiply.
Next to bottom, bright outline of background, blur diagonal, also with texture, blend mode set to luminance, low opacity, to allow bottom layer to show thru some and darken background of scene.
Bottom, copy of original, normal blend
Programs: Paint Shop Pro 9 and Painter 9