Reading the word ‘Ex 2 Thi’ on the Youtube video as posted by Kevin Le make me clueless about what the video is going to be about. Then, I notice in the video that there is Yamaha 135LC (Exciter in Vietnam) with an exhaust from a 2-stroke bike. Literally, that word means ‘2-stroke Ex’. When the bike is started and the exhaust started to make noises, it is really 2-stroke 135LC! This mod is not just an engine transplant but most of the part used are still maintained from the original 135LC engine. We can see the engine casing is still standard stock from the original 135LC. The job in making this modification possible is not easy in my opinion. So, we from MotoMalaya.net salute you, Vietnam modders.
You’ll want to see the video as the prove that the engine is really 2-stroke:
A very BIG thanks to Kevin Le for the tips.