theres a mark on the left side?i know there is a little line on the right side.i didnt see one i will have to take a look again.i am running a 140 right now but i still have to get it exactly right.its close right now but not perfect.its hard for me do jet mine where i live cuz my neighbors are bitches and call the cops whenever i try to ride so i can only do like 1 plug chop a day