user: Question: Which rider from the 1971 Isle of Man Junior TT 250cc final standings had a speed equal to 86.15mph?
Columns: ['Place', 'Rider', 'Country', 'Machine', 'Speed', 'Time', 'Points']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'Tony Jefferies', 'United Kingdom', 'Yamsel', '89.81mph', '2:05.48.6', 15.0]
SQL:

assistant: SELECT "Rider" FROM "Table" WHERE "Speed" = '86.15mph';