1. After a burnout, the friction of rear wheel becomes about zero on all bikes.
2. Empty splashes sprite
https://drive.google.com/file/d/0B33SqqrJ31baLXZYazBvX1JXdjg/view?usp=sharing
Suggestion.
On speeds less than about 5 km/h, it's preferable to make that bike steering wheel angle exactly match user input.
On speeds above 10 km/h, bike lean is controlled by user input (that's how it is done now)
And a smooth transition from 5 to 10 km/h between this two modes.