Japanese Titles: Enter Neptune!, The Identity of the Masked Boy
The mysterious MTB Rider is revealed to be Kyoichi Shido who is Makoto's older brother.
Kakeru: Looks like nothing but rocks here!
Sho: Good news, I saved a bunch of money on my bike insurance!
This is a reference to the GEICO commercials, where something bad happens, and someone says something like "Good news, I saved a bunch of money on my car insurance by switching to GEICO!"