The M365 is an impressive scooter, but it can't be perfect. The build quality is excellent, with the exception of the locking mechanism which pretty predictably fails after a fair amount of riding. It failed on me and could have seriously hurt had I not been kicking it at that moment.
Luckily it's pretty straightforward to address. While scooter share companies replace the whole mechanism with a metal collar to eliminate the issue entirely, you still want to be able to carry the scooter on public transport or into a store, or perhaps throw it in a trunk. For this reason I think it's worth it to order some aftermarket parts and strengthen the connection permanently.
Here are some good replacements as well as an easy method to remove the hook pin.
Points of Failure and Replacement Parts
The following components all require some TLC. Note that those of us in the United States have to send away overseas for this stuff. While our cities are no exception to the scooter boom, the modding scene lives largely in Europe. I recommend buying from indivual specialists but you can also find decent parts on eBay. For these mission-critical items, I would avoid direct Chinese replacements.
Hook (photo above left) - What locks into the groove and visible from the front of the scooter. Has a bolt head in the middle. As you can see, it is prone to shearing in half here.
Hook bolt, large fisheye bolt, or the 'jesus bolt' as it bears the pressure of the locking lever connected to the hook...which secures the whole thing. So it's a hidden but critical part.
Again Vilda has a great part.
Axis/hinge bolt (photo above right) - What the whole stem pivots on. Not the best design as it breaks at the groove in the middle. Find a replacement that is one thick bar all the way through.
If you look hard enough, you can find combo packs with everything you need.
Replacing each of these parts if pretty self-explanatory with the exception of the hook. The manufacturer probably inserted the steel pin holding it in place hydraulically so it's pretty hard to get out. You may have found that with a hammer and punch alone it doesn't even budge, but I was finally able to extract it after loosening it by drilling some holes.
- 5mm punch
- 5mm (around 3/16") drill bit
Start by propping the front of the scooter up on a bench or something and anchor the back wheel against the floor. The goal is to have downward momentum on the hook. Then drill 3 holes into the hook directly inline with the pin. Because the pin is held only by the hook and not the bracket it's mounted to, this turned out to be the secret to greatly reducing friction and freeing it.
Aim to drill into the aluminum and not the steel pin. You can hit the pin but stop as soon as you can. Don't go all the way through it. The improved hook designs all come with a new pin anyway, but you still want the old one loosened and not broken or it will be more difficult to remove in pieces.
With your holes drilled, another pass with the punch should take it out without issue. Prop up the base of the stem with a wood block and hammer it on a hard surface such as concrete. Avoid supporting the part you're striking with any other part of the stem, or you may damage it. I used a small block of wood to provide good support directly under where I was hitting.
Take note that the pin slightly tapers on one side. I found the pin was inserted from the left side, facing forwards on the scooter. That means you'll want to strike from the right side. If you look carefully at each pin end, you will notice one is slightly smaller than the other. That's the side you want to pound. See the photo of this pin above.
With the old (hopefully not broken) hook extracted, your replacement should be pretty easy to install.