I noticed the No 4 bike had a Yamaha sticker on it, so I found the Yamaha Malaysia website, and it seems they have a special class of racing for the "Yamaha Moped 135LC". That Video Clip seems to be from the Yamaha Moped 135LC Asean Cup series. Note: they call it a moped !!
Specifications:
Overall length x width x height: 1,945 x 705 x 1,065 mm
Seat Height: 770 mm
Wheel base: 1,245 mm
Minimum Ground Clearance: 140 mm
Dry weight/ Curb weight: 105 kg
Fuel oil capacity: 4.0 litres
Clutch type: Multiple Disk, centrifugal automatic
Transmission: 4-speed Rotating
Brake front / rear: Single disc brake / Drum Brake