So im going to change the oil on my 06' Ninja 500, Its the first one, i looked in my manuel, it said 10w-40. Thats just regualer engine oil. Now i went to Wally world and they had 4-stroke motorcycle oil...Whats the diffrence? Also there is no part number in my manuel for the oil filter nor is the a number on the one on the bike, any1 know off hand what i need? Let me know, Rep given for any1 helpfull!