After reading Matt Shumaker's project page: "My E-cumbent" I contacted him about any recommendations for very high power brushless RC motors. He recommended this:
HXT 80-100-A 180Kv Brushless Outrunner (eq: 70-55)
There's also this one at a slightly lower rpm/v and power:
HXT 80-100-B 130Kv Brushless Outrunner (eq: 70-55)
An RC controller can be used for them with details in Matt's project page.