I have a Weeride child seat, mounted atop my top tube.
I am concerned that if my handlebars turn abruptly, they will stab my child (please do say if there's a better term for this than stab). How do I manage this risk? I'm interested in both types of safety measures:
- active safety: to reduce the risk of handlebars turning abruptly;
- passive safety: to reduce the harm it the handlebars do turn abruptly.
Why it's a concern on some bikes only
With the shapes and sizes of my frame and parts, the handlebars happen to have just the right position and length to do that - please see the video and photos below.



I see many reasons why the handlebars could turn abruptly. The obvious ones are falls and crashes.
But I'm also concerned about that situation when they sometimes turn when I am stationary: perhaps while I'm seating my child in the seat, or adjusting the straps. While I have both my hands off the handlebars, the bike leans slightly, and the handlebars suddenly turn, perhaps because the front wheel turns rather than leans because of friction etc. I don't like quora but it's the best record I could find for this phenomenon: When the bike leans, what causes the front wheel to turn?. It's something that happens quite a bit and it's not really a problem if it wasn't for the relative position of my handlebars and the weeride.
My bike is fairly standard, it's a Giant Rock from probably around 2005. An entry-level hardtail MTB.
Ideas which I considered so far
Move the seat
I cannot move the seat, by design it is at a fixed distance from the head tube (the bar it sits on is telescopic, but it's the rear part that moves).
Replace stem/handlebars
Naturally I could replace the stem and/or handlebars. For example, longer handlebars would stop against the side of the seat. And shorter ones would just swing well clear of the child altogether.
Flanged BMX grips
I do need to get some new grips anyway, so it crossed my mind to get some flanged ones, also known as BMX grips. My logic is that they would both blunt an impact (larger object) and soften it (softer object). I think it's the best option, but I still think there may be a downside I haven't considered.
Turn limiters
Some kids bikes have turn limiters and I bet it's possible to install one on an adults bike. However, this wouldn't work for me. I do want to keep the ability to turn the handlebars 180°, because it allows me to easily put my bike in my car with just the wheels off (bike wheels, not car wheels).
Always keep one hand on the handlebars, even if stationary
It's free and simple, but not always possible.
Recap
How do I deal with this risk? Are my ideas any good? Are there any other options?