One thing is certain: The Motus draws attention, thanks to what is perhaps the most unique engine note in modern-day motorcycling. Powered by a 100-cubic-inch (1645cc), liquid-cooled, pushrod V4 built by Katech, a legendary Detroit auto-engineering firm, the so-called KMV4 sounds like half a NASCAR V8. One report from the twin Two Brothers Racing carbon-fiber exhaust cans brings bike nuts running. The KMV4 "Baby Block" is the literal and figurative heart of the MST, a clever mix of proven ideas and new technology that defines the attitude and character of this all-American machine. "What's more American than a pushrod V-motor?" asks Lee Conn, who, along with designer Brian Case, founded Motus. "A high-displacement pushrod engine could be hugely reliable, overbuilt and understressed, so it could last a long time." Katech, known for work on GM's many championship-winning endurance-racing cars, designed an exceedingly compact V4 that looks familiar to anyone who's ever studied a small-block Chevy.