Straight Outta Sanctuary: Honda CB1100R Restomod

Possibly the Last: Honda CB1100R from AC Sanctuary… 

In 1980, Honda unveiled their first-ever homologation special, the CB1100R. Based on the CB900, the single-seat sport bike boasted a 1062cc 16-valve DOHC inline-four producing 120 bhp and was designed for endurance racing, where it made an impact straight away.

“The 1100R began life as a batch of 100 homologation specials, eight of which lined-up on the grid for the model’s maiden race, the six-hour endurance event at Amaroo Park, Australia.” –Motorsport Magazine

That Australian event was the renowned Castrol 6 Hour race, and none other than Wayne Gardner and teammate Andrew Johnston took away the win. In fact, the organizers would bar the CB1100R from the 1981 race, deeming it a “race special” instead of a production bike.

No matter, the CB1100R would race successfully on several continents, and the road-going version was soon available (albeit not in the USA). The bike was an instant classic, the fastest production bike of its time, and one of the first proper race replicas from a major Japanese manufacturer.

“The Honda CB1100R is one of the select few no-compromise, high-speed motorcycles — machines that express, in visceral as well as functional terms, that their riders are humans of unusual two-wheeled discrimination. Of the roadrace-oriented specials in its class the Suzuki Katana, the Eddie Lawson Replica KZ1000R, and the one-liter Bimotas — only the Italian kit bikes approach the level of visual flash and exclusivity embodied by the Honda.” –Motorcyclist, 1982

Only around 4000 examples were ever made, with slight differences between the CB1100RB (1980/81), CB1100RC (1982), and CB1100RD (1983).

Of course, you might have noticed this ’93 CB1100RD is far from stock. It’s the work of none other than Hiroyuki Nakamura of AC Sanctuary, and it’s been given the full RCM (Radical Custom Manufacture) treatment.

The Japanese workshop is best-known for their Kawasaki Zed models, such as the KZ1000-powered A16R we featured last week, but they have tackled their fair share of Hondas…and this one came their way at an affordable price.

“The team decided to ‘build it however they like’ as a new demo vehicle for RCM craftsmanship at their sanctuary, but when they started work, T.M. [the client] came forward and said he wanted to buy it.”

Nakamura-san says these Honda builds do pose a challenge from a parts availability standpoint — spares just aren’t readily available like they are for the Zeds, especially when it comes to internal engine components. Only the team’s stash of carefully collected components made the build possible, so this project is both extra special and a bit bittersweet…

“I don’t know if I’ll be able to make a CB1100R RCM in the future, so I thought there was no point in holding on to it, so I decided to go ahead and use it… But the precious stock parts I had on hand have been depleted considerably, so for some reason I feel a bit sad…” -Nakamura-san

Nakamura says the engine was fully processed by the good people at DiNx, one of AC Sanctuary’s trusted partners for engine rebuilds.

“The crankshaft is journal-wrapped and dynamically balanced, and the cylinder is bored and then honed with a Lotterer H85A to achieve precise clearance.  The valve guides are replaced and the seats are cut to ensure uniformity, with a focus  on precision.” -Nakamura-san

The engine was then fitted with a gorgeous Nitroweld titanium exhaust. The front fork is an ExM package with Öhlins inverted forks — a special package released from AC Sanctuary’s parent company — and the bike is rolling on 17-inch OZ Racing wheels and Brembo brakes.

“17-inch wheels…are a perfect match for the CB1100R, which has a roll axis with the head pipe positioned lower on the frame than the CB-F series!” -Nakamura

Of course, frame modifications were made to accommodate the wider yet smaller-diameter wheels, including a shift in the angle of the rear shocks and the fitment of a Sculpture swingarm with a width of 295mm.

Nakamura says that while the exterior coloring may appear standard at first glance, it’s actually a “slightly twisted” design wherein the red and blue are candy colors with slightly darker tones, and the logos on each part are painted on — not vinyl — for a higher quality finish. They also chose to reupholster the seat in black instead of the standard red, as red shows dirt too easily.

The upper cowling was lowered 10mm along with the cowling stays, and the screen was cut by hand. Nakamura says this makes the “face” of the bike look slightly smaller, “which is really cool.”

The cockpit contains a triplet of gauges from Stack, set in a one-off carbon fiber instrument panel made specifically for this build. The electrical system was completely revamped according to modern standards, and the build took a total of two years…partly due to the difficulty of procuring parts.

This CB1100R restomod is nothing short of incredible, but Nakamura fears the impact of rising prices and limited inventory both for donor bikes and replacement parts.

“In the future, it will become increasingly difficult to realize RCMs for classic bikes, let alone the air-cooled Z series. To be honest, the CB1100R is particularly difficult, and at this stage I honestly believe that this RCM-630 may actually be my last.”

Follow the Builder

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

More AC Sanctuary Restomods…

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 […]

860cc Kawasaki Z2 Restomod - RCM-617 from AC Sanctuary, inspired by Aitsu to Lullaby…   Most of us know the story of the Kawasaki Z1. Introduced in 1972, the 903cc UJM superbike was the fastest and most powerful Japanese four-cylinder ever […]

Straight Outta Sanctuary: Honda CB1100R Restomod - Possibly the Last: Honda CB1100R from AC Sanctuary…  In 1980, Honda unveiled their first-ever homologation special, the CB1100R. Based on the CB900, the single-seat sport bike boasted a 1062cc 16-valve DOHC inline-four producing 120 bhp […]

Zed’s Not Dead: Kawasaki KZ1000 “A16R” Restomod - KZ1000-Powered “A16R 005” from AC Sanctuary…   Hiroyuki Nakamura and his team at AC Sanctuary are famous for developing some of the fastest, sexiest restomod motorcycles on the planet. Though they work with many different […]

Thundering Super-Sport: Honda CB900F Restomod - RCM-604 by AC Sanctuary…  When the Honda CB900F first appeared in 1979, it wasn’t available in the States, as Honda was worried it might steal the thunder of the mighty CBX. American riders grew green […]

King Zed: Kawasaki “KZ1135” MKII Restomod - Kawasaki KZ1000 MKII from AC Sanctuary…   The Kawasaki KZ1000 MKII was the 1979-80 version of the liter-sized Zed. It received some nice upgrades over the previous model, including fresh bodywork, larger carbs, electronic ignition, […]

RCM-632, Unveiled: Kawasaki Z900RS Restomod - Z900RS built to AC Sanctuary’s tastes…    In 2017, Kawasaki introduced the Z900RS, a 109-hp naked retro that recalls the storied air-cooled inline-four Zeds of the 1970s. “You remember the 1970s, when things were simple, […]

Air-Cooled King: Kawasaki “GPz1170” Restomod - A Warhorse Reborn: GPz1100F from AC Sanctuary…   In 1981, Kawasaki launched the GPz1100 to recapture the Superbike throne. It would be the most powerful Z1-based machine ever, offering 109 horsepower from the fuel-injected, air-cooled 1089cc […]

Radicalized: Suzuki Katana 1100 Restomod - Final Edition Katana, Radicalized by AC Sanctuary…   In 1980, the original Suzuki Katana 1100 rocked the motorcycling world with its angular, space-age design. It was the vision of legendary German designer Hans Muth, who’d been […]

Ninja Type-R: Kawasaki GPZ900R Restomod - AC Sanctuary gives an original Ninja the Type-R treatment…  Introduced in late 1983, the Kawasaki GPZ900R — aka the Ninja ZX900 — was the earliest member of the Ninja series, and it changed sport biking […]

Ice Cool R: Kawasaki Z1-R Restomod - Kawasaki Z1-R from AC Sanctuary…  As everyone knows, the arrival of the Honda CB750 in 1969 kicked off the superbike era. Over the next decade, a two-wheeled arms race between the big four Japanese manufacturers […]

Restomod Reborn: Kawasaki KZ1000MK-II - 1105cc Kawasaki KZ1000MK-II by AC Sanctuary…  The Kawasaki Z1000MK-II appeared in 1978, largely as a response to the Suzuki GS1000 and Honda CB900F. Known as the KZ1000MK-II in some markets, the machine had beautiful new […]

Mark II Missile: Kawasaki KZ1000 MKII Restomod - AC Sanctuary’s MKII Missile…  In 1979, Kawasaki introduced the KZ1000 MKII, which offered new angular styling and a slight power boost out of the 1015cc DOHC inline four engine, now making 93 bhp. The crank […]

Déjà Vroom: Kawasaki “KZ1165” Restomod - RCM-554: 1165cc Zed from AC Sanctuary… The Kawasaki KZ900 was the direct successor of the mighty Z1. At the time of its introduction in 1972, the original 903cc Zed was the largest, most powerful four-cylinder […]

Resto-Monster: Honda CB1100F Restomod - 1123cc Honda Restomod from AC Sanctuary…  In 1983, the Honda CB1100F arrived as the company’s king sport bike, designed to battle head-on with the 1100-class superbikes from Kawasaki, Suzuki, and Yamaha — bikes that were […]