Grom bike

Honda Grom

The car guys have been enjoying engine swaps for years. It’s the simplest and most reliable way to get extra horsepower—which is why we see RX7s tooling around with 6.2-liter GM V8s, and tiny Honda Civics with Acura power. Motorcycles are another matter, though. It’s an engineering nightmare, and you obviously lose the stealth aspect, because the motor is on display. But that didn’t dissuade Cole Mishler, who has just built the ultimate pocket rocket: A Honda Grom with a lithium ion power…