So I also made a racing game, and I made really thin roads, but then any time my tire would go offroad, I'd slow down. So it was a tense and perfect timing situation. I tried making the roads a bit bigger and then maybe only thin in places. A constant thin road makes me feel like I'm on a tightrope. If that's the precision you want, go for it. Widening the roads would balance difficulty.
The change you made allowed me to recover in turns and just lose a little time instead of the huge 10 second penalty.
Haven't tried it on mobile, but may give it a try later.