Hi folks new guy here names kelv . I have a 2012 sinnis stealth 125 got it as a project bike an for winter months as I despise driving and don't fancy taking my gsxr 750 out in snow . .....anyways got 125 stealth and it will not start ,seems like there is too much air even from a makeshift airbox with only a 8mm hole in ,now and then it will fire but only runs for 5 seconds or so ....thats with the idle screw all the way out and completely random when it fires up...also it'll run off starter fluid ,now I've tried everything different air boxes,filters,jets,floats,cleaned an stripped carbs a million times ,idle screw,fuel screw the lot , even made a sealed airbox which got the bike to run but then backfired and blew it to bits (was only a thin plastic sweet tub) ......any ideas welcome as I am completely out of them at the moment , I should also add it has an aftermarket end can and did come with a come filter on