In the 13th stage of that race Competition , he collapsed Motion and died Death during the ascent Self_motion of Mont Ventoux .

Near the summit of Mont Ventoux , Simpson fell Motion off of his bike but was able to get back on it .

The post-mortem examination Scrutiny found Know that Simpson had taken Ingestion amphetamine and alcohol , a diuretic combination Cause_to_amalgamate which proved Incident fatal Killing when combined Cause_to_amalgamate with the heat , the hard Confronting_problem climb Self_motion of the Ventoux and the stomach complaint .