Question: when did yamaha start fuel injection on dirt bikes
[{'answer': 'September 8 , 2009', 'provenance': [{'wikipedia_id': '11214440', 'title': 'Yamaha YZ450F', 'start_paragraph_id': 23, 'start_character': 0, 'end_paragraph_id': 23, 'end_character': 18, 'bleu_score': 1.0, 'section': 'Section::::Fifth generation YZ450F 2010-2013.\n'}]}, {'provenance': [{'wikipedia_id': '11214440', 'title': 'Yamaha YZ450F', 'start_paragraph_id': 23, 'start_character': 0, 'end_paragraph_id': 23, 'end_character': 674, 'bleu_score': 0.9046391672996711, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11605292029558420933}, 'section': 'Section::::Fifth generation YZ450F 2010-2013.\n'}]}]