Lich Bane

The Lich Bane is an ad caries weapon it gives them an extra 110 damage after each ability. And because it is a 1000 gold in between the two building items and the item it's self it takes to long to make. To make it an ap weapon and fix the time sitting on sheen an item that works off of ad dame; I would sugest replacing Blasting Wand for the Hextech Revolver.

This would reduce the final items cost to 600 gold and reduce the time spent saving for Blasting wand. You could also give Lich Bane spellvamp 20%. This would create new building options for for other ap characters to go for spell vamp other than the three chaps that have natural spellvap abilities. this change will improve the item and make a good ap item.

Or you take the +200 mana make it health and have it work the same as Sheen with and you have a ad weapon.

As a side note their is only two ap weapon item that is not jungler specific that gives spellvamp Hextech Gunblade and Hextech Gunblade to the to the 12 life steal items for ad caries.