Givrins, Switzerland - Former Formula One world champion Michael Schumacher has called off a planned start this weekend in the German superbike series, saying he was still feeling the effects of a crash two months ago.

The record seven-time F1 champion was due to compete in the first race of the German IDM series at the Lausitzring in eastern Germany.

"Unfortunately I have had to call it off because I am not yet ready," he told German Press Agency dpa in Givrins, Switzerland.