Bike/Car crash - Driver wants to take me to court

Tell him (if you manage to get in touch with him, that is) that you have a counter claim for the expensive bike he trashed with his insane driving + an additional claim for compensation for the head injuries and trauma.

When you fail to hear anything further from him, that is probably the time to pursue your claim as (it would appear to me anyway) that he IS just a chancer and didnt want to go through with anything.

You may even be able to use that fact against him in court

Counter claim sounds like a good way to scare him off. If its too much stress to deal with you can always drop your claim (provided he's dropped his by this point). Sucks to have lost out but better than getting a bill from the court.