Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_78 (laps INTEGER, grid VARCHAR, bike VARCHAR, rider VARCHAR)
### Question:
What is the highest Laps, when Bike is "Yamaha YZF-R1", when Rider is "David Checa", and when Grid is greater than 18?
### Answer:
SELECT MAX(laps) FROM table_name_78 WHERE bike = "yamaha yzf-r1" AND rider = "david checa" AND grid > 18