So many people come and visit this country and want to scoot around on a motorbike to get to some of the out of city things that are around Chiang Mai. This can be a good idea if you actually are capable of driving a motorbike and honestly, there really isn't that much to it. I've been to and lived in a number of other places in this country and it is just more of the same. In one way, Chiang Mai is easier because the roads are in pretty great shape here and there has been a lot of forward planning to ensure that there actually are enough roads for most of the demand that traffic dictates.
Obviously there are exceptions but if you are just traveling here on holiday, you are pretty unlikely to end up in rush hour gridlocked traffic unless you are very unlucky.
One thing though, that you can get away with in most of the rest of the country that you can't really get away with here, is dodging the police if you are operating a motorbike without a license.
The thing is, the police proabably aren't truly interested in keeping the roads safer, they are interested in collecting money from people that don't have the correct certification and in most situations, unless you have a legitimate international license the likes of which I don't even know how someone acquires, you aren't going to have what they are looking for because they aren't actually looking for a license, they are looking to fine you right there on the spot.
This is something you just kind of have to come to terms with if you are visiting here, or like me, living here.
I have some tips to save yourself a bunch of headache though and maybe even get you out of it altogether.
comply, show ID
If you end up in a checkpoint where they ask for your ID or license, provide them with any sort of photo ID. If you have a driving license in your home country, show them that. Then, answer in the affirmative if they ask things like "is this international?" or "is this for motorcycle". Remember, if you tell a little white lie here this isn't any different than them purposely fleecing visitors. Safety is not their concern hence the fact that Thailand regularly ranks in the top 3 for most road deaths of any country in the world.
Be friendly
Acting like a "Karen" might get you out of situations in USA but it is only going to make things a lot worse for you over here. Thai police are definitely on a power trip, but they will treat you with respect if you do so as well. Throwing a fit will only make the fine larger, so keep it cool.
If you are fined, pay on the spot
Some people are upset and refuse to pay on the spot for some receipt that is probably not official anyway. IF you play this game you are going to lose. They will in fact allow you to go to the station and take care of your "ticket" there but now you have just turned a 5-minute transaction into an all day affair and trust me when I say that they are going to make this take as long as possible. In order to save $20 or so you have just wasted your entire day. Also the system is not going to change just because you think you are going to go over the heads of a corrupt street officer. The entire organization is in on it so it's not like if you ask to speak to a manager that internal affairs are going to get involved and thank you for exposing their system.
do NOT record them
This is a fantastic way to super-escalate the situation
Keep your ticket if you get one
This is one of the rather amusing things about routine traffic violations in Thailand. If you are issued a ticket, there is an unofficial rule that you cannot be charged for that same made up crime for 7 days. So if you got a ticket for driving without a license, you can carry on doing so for another week. In a country with actual road rules, driving without a license would mean you are removed from the streets and your vehicle is towed at your own expense. In Thailand the infraction was never about a law to begin with so they don't really care. This 7-day grace period is likely in place so that the population don't riot and burn down police stations and yes, this is something that actually does happen and when it does, the police just get out of the way and let the people burn it.
Keep that ticket forever
Using my own system, I have had the same "no license" ticket in my motorbike compartment for several years and if I see a checkpoint, I slow down, pull out the ticket and then show it to the guy who is flagging down vehicles. Chances are, this person seeing a ticket AT ALL is going to convince him to flag you on through because it is such a common thing for there to be multiple checkpoints all over the city and surrounding areas on the same day.
IF they guy happens to look at it closely (and with dozens of this exact situation happening to me they NEVER have) and they say "hey this is from last year!" you can just claim ignorance. Just say "oh, I didn't know" then be polite and comply. This is a bullshit situation anyway, so you may as well play along.
Carry small bills
The fine is often simply made up on the spot and if you open your wallet and you have a bunch of 1000 Baht notes and several 500's, you can be assured your fine will be at least 500. However, if you have a few 100's in there and then just chump change, you can probably get away with just paying a couple hundred. They are not going to ask anyone to do a QR bank transfer because that is a little thing that some people in the legal system refer to as "evidence."
I tend to look at it from the standpoint of which would you rather have? A mildly corrupt police force looking for kickbacks, or a situation like we have in the United States where you would never be allowed to drive anyway?
Follow these above steps though and there is a good chance you might just avoid getting fined at all. If you do get fined, treat it as a vacation experience. Fighting it is a waste of time and the system is not going to change.