as mentioned by saboor
honda CG125E has wasted spark ignition - the plug will fire everytime the cylinder reaches TDC no matter if on the compression stroke or exhaust stroke.
infact - any single cylinder motorcycle with its pulser, points on the crank or magneto will be wasted spark - even CD200 twin is like that - it wastes a spark on each cylinder.
Honda CB125, CB185 etc engines are not wasted spark - their triggers are fired from the cam.
btw - two stroke are not just only fires on every stroke, - in a 2 stroke every upstroke is compression and it results in a power stroke.
the exhaust happens as it descends and opens the exhaust port, at the same time the transfer ports open to transfer new mixture from the crankcase to the cylinder.
everytime the piston rises a negative suction is created in the crankcase of a 2 stroke and the intake stroke takes place.