Installing a temperature switch to the outside of a brush DC motor, to avoid overheat damage, any input?

I’m looking for any input, advice, knowledge, experience on this subject:

This is for my E300 Razor Scooter, which I have modified the controller shunt to allow more current and plan on over volting soon as well.
I’m planning on installing a $2. high temperature cut off resetting switch, like those sold on Aliexpress in various set temperatures and both normal open and normally closed styles, to the outside of my OEM brushed 24v 250w DC motor, to avoid overheat damage.
Kind of like that famous Electric cars suspenseful pursuit scene from the classic1971 Sci Fi movie “THX 1138”. Where they have to wait for the motors to cool off or something, to get going again.
So that if and when I’m pushing my motor too hard for too long, up hills etc., the controller will shut off the motor before any damage.
I just wait 15 minutes or more for a proper cool down and start riding my scooter again, no harm done is the plan.
I see I should be able to wire a normally open temperature switch to the controller’s brake lever circuit which is also normally open, but closes and cuts off the motor when the rear brake lever is applied.
I suppose super glue might be the best simple thing to use to attach the switch to the motor body. Super glue should be able to take the heat and also conduct the heat to the switch.


These Razor brushed DC motors, as well as all the various watts sizes and voltages sold online, don’t have Any high temp thermal cut-off-protection build into them. In spite of the fact that high priced E-bike and E-Scooters do have cut off protection and many of our home electric appliance motors do as well, such as our vacuum cleaners, clothes washers, etc.

Surprisingly, I haven’t see Anyone in a forum installing an after market high temp thermal cut off to these motors. But I have seen on YouTube, people over heating and permanently damaging/killing these DC brushed motors when over current/over volting.
These lower watts motors are much cheaper and much lighter, consume less power than a larger motor when not over worked and can take a beating, a real sweet spot. And fitting a much larger watt motor can be impossible in the OEM motor’s location.
None of these brushed DC motor companies seem to list the high temperature limit of their motors which depends on the materials they use. I’ve tried to ask these motor companies but haven’t gotten a reply.
From what I’ve found online concerning DC motors in general, the heat is mostly generated in the electrical energized spinning Armature.
An estimate to be that the stator’s maximum temperature which it can reach/be exposed to for short periods of time without the risk of permanent damage, might be around 266 F (130 C), before the Armature’s winding’s insulation begins to melt off. When this occurs, the outside metal case temperature of the motor, where the heat dissipates from, will be less, say approx. 176 F (80 C).
I suppose a 149 F (65 C) high temperature switch might be about the right temp to stop the motor for a cool down. No might have to go lower in temp…hmm.
Currently I stop my scooter rides occasionally to check the motor’s outside temperature with my hand from time to time, especially after steep hills.
I’ve read online that the typical human can tolerate briefly touching something that’s about 60 to 65 C (140 to 150 F).
If I can’t touch the motor without releasing to the count of 4 seconds, then I’ll take a 15 minute brake for it to cool down.

Has anyone tried installing a high temp cut off switch?
Anyone know what temperature the motor’s outside case might reach before motor damage?
Any suggestions, comments, criticism, etc?!

Thank you for your time & help!