This motorcycle-powered kei-car is a match made in motoring heaven

Some of the most wonderful, exciting, and soul-stirring engines are to be found in motorcycles, which can pose as a barrier of entry for those who aren’t brave/ballsy enough to mount a crotch rocket to see what all the fuss is about. 

If you are the sort of chap who needs the safety of a metal body, and the comforts of a chair, fret not, all you need to do is to find a light enough car where a motorcycle engine can work its magic. A car as light as this classic 1972 Honda N600 kei-car would do nicely.

You won’t find the N600’s original 34kW 598cc inline-2 engine under its hood. Instead therein lies a 782cc V4 engine from a 1998 Honda VFR 800 Interceptor sport bike, which puts out 86kW at 10,500rpm. While its original twin-potter maxes out at 9,000rpm, the motorcycle engine can spin up to 12,000rpm. Piped through a Supertrapp exhaust, this N600 sounds closer to a Formula single-seater at full chat than your average kei-car. 

Honda VFR 800 Interceptor.

The engine however is only one part of the changes done under its skin. Instead of driving the front wheels, power is sent through to the rear via a proper propshaft. Its outmoded 70s suspension on the other hand, has been thoroughly updated with all-round double-wishbone assemblies taken from a first-gen Mazda Miata (NA MX-5), while a Ford-sourced differential sits between the rear axle on a narrowed Miata subframe.

That's damn cool.

All said and done, this reworked N600 tips the scales at 635kg, which is slightly more than the car’s original mass of 550kg. But who are we to complain when it has a 250 per cent power bump? 

If there is one drawback to this whole package is that it uses a six-speed motorcycle gearbox. While gear changes are done through a pair of paddle shifters, you’d still have to operate its motorcycle clutch, which is better operated with fingers rather than feet, and to top it off, it doesn’t come with a cog for reversing, so plan your parking approaches carefully.

What's your ultimate lightweight engine-swap? Tell us about it in the comments.