Hello all just being do a service on the CBR125R i purchased last week (air filter, oil filter, oil, new bulbs/LED replacments and spark plug) i replaced the old airfilter with a sexy new K&N woooo lol and the engine started fine for a while... then kinda stutered and died sounds to me like a fuel starvation... or so i thought... i took the K&N airfilter out and put the old one back its under tank so i had tank off and put all the pipes back and sealed. i have now drained the batt trying to get this thing to start the oil is new oil 10-40 full synth and filter is good. spark is sparking and nice and new although the spark plug has a diff P/N its just got an R in it for resistor or something the guy was on about but i put the old one back in (weak spark and sooted) and still no joy. batts now on a quick 80% charge then im gonna try again any ideas or advice i know fuel is in the system as i can smell it in the Cylinder