Honda CB1100F Restomod – BikeBound

1123cc Honda Restomod from AC Sanctuary… 

In 1983, the Honda CB1100F arrived as the corporate’s king sport bike, designed to battle head-on with the 1100-class superbikes from Kawasaki, Suzuki, and Yamaha — bikes that had been a stable second sooner within the quarter mile than Honda’s outgoing CB900F.

 

The CB1100F’s 1062cc DOHC four-cylinder engine boasted greater pistons, hotter cams, redesigned combustion chambers, and improved carburetion — all of which added as much as 108 bhp, almost 20 extra ponies than its predecessor. The CB1100F might reportedly hit 67 mph in first gear, and riders appreciated the considerable energy down low in comparison with its rivals:

“In a three-way shootout between the CB1100F, Kawasaki GPz1100 and Suzuki GS1100ES, Cycle journal whipped off a standing-start quarter mile in 11.03 seconds at 121.78mph aboard the Honda. That was barely slower than the GPz1100 and GS1100ES (10.8 and 10.88 seconds, respectively), however the upside of the 1100F’s longish stroke was spectacular low-end grunt for real-world driving.” –Motorbike Classics

 

The superbikes of the early 80s weren’t identified for excellent dealing with — in any case, engine output had far outpaced body and tire expertise. Nevertheless, the CB1100F benefited from additional body gusseting, revised geometry, and a box-section swingarm. Cycle World was duly impressed:

“There isn’t a extra steady bike. Dial up the Honda’s damping to full throughout, jack up the fork stress to eight.0 psi and shock spring preload to quantity three place or larger and set out for the meanest, roughest, quickest sweeper you will discover.” –Cycle World, 1983

Nevertheless, there’s a lot to be stated for updating the suspension, brakes, and electronics of those outdated air/oil-cooled beasts, and nobody does it higher than Japan’s AC Sanctuary. Although they’re finest identified for Z-series builds just like the Z1-R restomod we just lately featured, they bring about their expertise and experience to different many makes and fashions of the period…though founder Hiroyuki Nakamura says it’s getting laborious to search out appropriate donor bikes:

“The variety of bikes in good situation has decreased considerably, and the classic bike market has entered an period of nice change. This isn’t only for Kawasakis; it has additionally occurred to Hondas from the 80’s, and the CB1100F/R has grow to be tough to acquire.”

 

This was case for the CB1100F you see right here, dubbed “RCM-525” — all AC Sanctuary bespoke builds use this naming conference, the place RCM refers to “Radical Development Manufacture.” What’s extra, Nakamura says inner engine components for the CB1100F are now not accessible — fairly the issue for a workshop’s whose excessive diploma of perfectionism calls for a full engine rebuild:

“That made the construct course of was completely different from the air-cooled Z RCM fashions, as we needed to patiently wait to acquire new components by way of public sale.”

With time, persistence, and quite a lot of “twists and turns,” the engine was rebuilt with 1123cc Wossner Pistons, a 13-stage spherical oil cooler, Yoshimura / Mikuni TMR MJN 38 carbs, and extra.

A Sculpture steering stem and swingarm designed for the Z-series was tailored for the Honda, and it was given Öhlins suspension at each ends and a set of 17-inch OZ Racing wheels with meaty Pirelli Diablo rubber.

Nakamura says the distinction to the usual bike is way from refined:

“After upgrading the consumption/exhaust system and ignition, the bike delivers large, torque-laden energy. The bike has been reborn, and has an fascinating energy supply that may be absolutely skilled compared with the conventional bike.”

Nakamura says he felt a robust connection to this bike, however he fears it could be the final of its sort:

“New engine components have gotten increasingly tough to acquire because the situation of the bottom automobile deteriorates. These components are a robust headwind for RCM. Maybe this RCM-525 would be the final of the RCM CB-F&R sequence.”

Let’s hope this CB1100F restomod isn’t the final to roll out of AC Sanctuary!

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