The police is setting up checkpoints daily at Sukhumvit road, days and night. Now they are tougher and they may tow your vehicle, or/and ask 1000 baht for having no helmet. Thai driving license or International driving licenses are mandatory. They are tough with tourists, but also with Thais, who complain about the high price of the fines in the social networks (compared their low salaries). The driving schools are full and you may wait weeks or months to have an appointment to pass the driving license. It is worth doing it if you are an expat and will avoid the hassle to spend time paying, and going back and forth to the Police Station then the towing parking etc… if your motorbike is towed you topically have to pay 1000 baht to get it back, this is adding up with the fine and the taxi motorbikes to go here and there.