What level should you use a thunderstone on your Pikachu

i wouldn't evolve pikachu at all i would keep the stats how they are but if you want raichu your speed will fall but everything goes up slightly so i hope you use this information well if any of you ppl need if you need any help on Pokemon platinum heres my trainer number 13387 and type in ash ( and im a thunder collector ;)How ever if yor playing second gen. You may want to wait until lvl50 or at least up to 41 so pika uh would learn thunder(lvl41)or light screen (lvl50) after that he dosen't learn any new moves so feel free to evolve him after that.