Radical Six: Honda CBX1000 Restomod

RCM-688: The First-Ever CBX Restomod from AC Sanctuary…  

We’ve seen many masterful restomods from Hiroyuki Nakamura and the crew of AC Sanctuary — an assortment of Zeds, Ninjas, Katanas, CB1000R’s, and more. But we’ve never seen a six-cylinder machine from the Japanese “restogods”…until now.

This Honda CBX1000 was built for repeat customer Mr. Chen of CHMoto — a dealership located in Taipei, Taiwan. Says Nakamura-san:

“As of March 2025, nearly 700 RCMs have been produced, and the CBX1000 is a unique model!”

That’s right, this build — RCM-688 — is the only CBX that AC Sanctuary has ever produced as an RCM (Radical Custom Manufacture) machine. As with all RCM builds, it’s comprised of parts from world-leading manufacturers like Öhlins suspension, OZ Racing wheels, Brembo brakes, and
other top-notch products worthy of an RCM.

As AC Sanctuary had never converted a CBX1000 to 17-inch wheels, they began by carefully collecting measurements and data to ensure optimal geometry and fitment. The donor was originally a mono-shock “Pro-Link” model, but Nakamura and crew converted it back to the more traditional twin-shock arrangement. A Sculpture braced swingarm supports the wider rear tire.

At the same time, they modified and reinforced the frame, which was always a bit too flimsy for the power and weight of the big six-cylinder engine.

Nakamura-san says the engine was the most time-consuming aspect of the build. It was leaking transmission fluid, and parts for these bikes are not so easy to come buy. He ended up having ARP here in the US manufacture a number of internal parts for the motor, which was completely disassembled and rebuilt from the ground up.

The Nitro Racing titanium exhaust is a one-off masterpiece.

“Built at the owner’s request, it is an elaborately crafted exhaust that is suitable for an RCM, equipped with dual silencers, one on each side.”

In order to mount the wider rear wheel and tire, it was necessary to offset the drive chain significantly, which led to interference with the left exhaust pipe and bracing. Fortunately, the AC Sanctuary crew was able to rework the various parts to work together.

A one-off instrument panel was created from aluminum and carbon plate to hold the three Stack gauges, affixed to the upper fairing bracket.

Nakamura and team have decided to enter RCM-688 in the Tokyo Motorcycle Show next weekend, March 28-30. If any of our readers are lucky enough to attend, you can see the bike in the Sphere Light booth.

The build was much more challenging than expected, but all the hard work was worth it.

“The CBX1000 was extremely difficult to make, taking three years to complete. We didn’t expect it to take this long, so we would like to take this opportunity to apologize for making you wait so long. The RCM-688 will depart on a ship bound for Taiwan in April! This machine will surely be a big hit when it is raced in Taiwan! Thank you to Mr. Chen of Taipei CHMoto and the owner!”

Build Video

Below is a short YouTube video of the build.

Follow the Builder

Website: www.ac-sanctuary.co.jp
Facebook: www.facebook.com/ac.sanctuary

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