Many thanks to Ayako for tweeting the link!
Suzuka Circuit has posted that Keanu Reeves will attend The 38th “Coca-Cola Zero” Suzuka 8 on Saturday, July 25 in Suzuka CIty, Japan.
Update: Suzuka has tweeted that Arch Motorcycle will be there and they list times.
According to Niconico Live, he will drop the flag to signal the start of the final race. In addition to showing t˙e KRGT-1, he will also do a talk show if I understand the translation correctly.
Update X2: Many thanks to @tomgurnee who tweeted that he saw Keanu at LAX today. The tweet was posted about 2.5 hr ag0.
Note: When he went to the races in Italy, he toured motorcycle company headquarters, so wonder if he will visit Suzuki, Yamaha and Kawasaki while he is there.