Two-Stroke Supermoto: Honda CRF / CR500 Hybrid!

Honda CR500 Supermoto

MCNC builds a CRF-framed, CR500 supermotard!

Introduced in 1984, the Honda CR500 would become one of the most infamous motorcycles of all time, a two-stroke open-class monster that made more than 60 hp in stock trim — still more than a 2021 Honda CRF450R motocrosser. The power delivery has been described as nothing less than lethal, requiring the rider to remain focused at all times:

“The CR500 has a reputation as being an animal, but when you are thinking straight and everything is together, it’s a lovely machine. But as soon as your mind wanders you tire and become a passenger, that’s when a 500cc two-stroke becomes a beast that will bite you…” —MCN

Honda CR500 Supermoto

Of course, the mystique of this two-stroke apotheosis has been luring riders for years, and one of them is our friend Nicolas Baux (@atelier_mcnc) of France, who built the Moto Guzzi 850 T3 café racer, “La Macchina,” we recently featured. Nicolas’s first bike was a two-stroke 1980 Yamaha RD80LC, which helped solidify his love of smokers.

Honda CR500 Supermoto

Years later, he picked up a 1992 CR500, which he rode for years before getting the itch to put that legendary engine in a more modern chassis:

“In 2012, after riding my supermoto Honda 500 CR for 8 years, I decided to modify it by mounting its engine in a 2006 450 CRF frame. For fun. That day I cut up my first frame!”

Honda CR500 Supermoto

Nicolas had to heavily modify the frame to make the old engine fit the new chassis, and also design and machine an assortment of brackets, supports, and adapter plates. Not only was all of the work worth it, but it triggered his passion for heavy modification:

“It’s the first motorcycle that I really modified, and it was a revelation: when you start cutting a motorcycle frame, you become addicted!”

Honda CR500 Supermoto

Below, Nicolas gives us the full story on the build of his CRF-framed CR500 supermoto!

Honda CRF/CR500 Supermoto: In the Builder’s Words…

Honda CR500 Supermoto

After riding for several years with pleasure on my 1992 500 CR, with its original frame, I decided to give it a little makeover by installing its engine in a more modern chassis, that of a 450 CRF from 2006.

Honda CR500 Supermoto

After buying a nice donor and reselling the engine, wheels, brakes, and everything that was not useful to me, I positioned the engine of the 500 in the aluminum frame.

At this point, it was very clear that the Y of the frame was not located in the right place, since the large exhaust of the 500 was in the middle of the frame — no matter matter, I have a saw!

Honda CR500 Supermoto

A few minutes later, I could finally take the measurements of what would later be the new Y. I used a template that I cut in foam to take the dimensions, then I validated it by manufacturing a plastic test piece. Once the dimensions had been validated, we could then machine the final aluminum part.

Of course, I also had to make other parts such as the lower supports, the cylinder head mounting, the high voltage coil support, and the airbox adapter plate.

There were also modifications that had to be made to the frame and the engine at the level of the gearbox, so that the rear shock absorber could clear. The FMF exhaust is completely original — only the silencer needed a little touch-up and special mounting brackets.

Honda CR500 Supermoto

The tank had to be heated slightly to clear the cylinder head, and the radiator mounting had to be redone to make a good connection.

Honda CR500 Supermoto

After fitting the bike with new wheels, good six-piston Beringer brakes (the best of the best), we ended up with a very exciting bike to ride and with a fabulous look.

Honda CR500 Supermoto

It’s the first motorcycle that I really modified, and it was a revelation: when you start cutting a motorcycle frame, you become addicted! The next one will also be a mythical 500, but very different… to be continued!

Build Photos

Honda CR500 Supermoto Honda CR500 Supermoto

Actions Shots

Follow the Builder

4 Comments

  1. I love reading all of your articles. The builders of these bikes are more than engineers, they are artists.

  2. I prefer riding the steel framed 500s. The aluminum framed 500s are like riding Jack hammers.

  3. They “look” great. But BikeBound NEVER GIVES US HOW THEY REALLY RUN!! A little 0-60 would help and give us some semblance of performance, wouldn’t it? I don’t want a trophy!! i want the beast to run as good as they look!! BikeBound, can you do anything about that or not?

    • We hear you! In our interviews, we do ask the owners and/or builders how the bikes handle and perform — while many of them have weight and hp numbers, few have actual 0-60 or top speed data. That said, we will push for more specific performance data moving forward, as this is great feedback and we’re as curious as you are 🙂

Leave a Reply to bikebound Cancel

Your email address will not be published. Required fields are marked *

*