Aluminium pulleys are more prone to wear and self sharpening.
The tooth sharpening makes possible to strip and cut belts. Being practical in performance terms a plastic pulley should weight less, is cheaper to replace and less delicate than the aluminium counterpart.
But for the looks, the aluminium pulleys are killer and more 'eye candy'.
[quote=MugenDrew;2684554]BATTERIES are for FLASH LIGHTS, gasoline is for cleanin parts, alcohol is for me to drink and well NITRO...everybody know thats for racing.[/quote] :D:D:D