Is it doable or advisable?
There's a nice Kona 24" wheel racer just popped up for sale but my daughter is more MTB inclined so wondering if I could convert it.
Anyone done similar?
Few pals have done it the other way around and converted flat bar Isla bikes to drop bar CX bikes for their kids, can't see why you couldn't do it the other way around. Crack on.
What brakes does it have? What are the clearances like? Gearing?
Currently on cantis, 3 x 8 gears, drop bars..
Hard to say anything without knowing more details but I suspect the main issue you’ll save will be tyre clearance, which will probably mean that at best you don’t end up with something you could call an MTB, more of a hybrid or a flat-barred CX. It may also be a bit short in the top tube, but that’s not necessarily a problem.