Gold Wing-Style Forks For Future Hondas?

[Hugh Janus]

Patent drawings show Honda looking at wishbone-style front suspension for future models, like the CB1100. (Japanese Patent Office/)

In adopting double-wishbone front suspension for its range-topping Gold Wing in 2018 Honda embraced the same thinking that pushed the likes of Norman Hossack and John Britten into ditching telescopic forks, and now it looks like the company has ideas to spread the technology further across the range.

The firm has filed patent applications in Japan for wishbone-style front suspension on bikes at extreme ends of its range. One shows the system adapted for an across-the-frame four-cylinder—in this case the CB1100—while the other reveals how the design can be modified to fit the C125 Super Cub scooter.

Unlike the Gold Wing, the CB1100 relies on a retro-heavy overall design that favors a conventional fork arrangement, making a wishbone arrangement challenging. (Japanese Patent Office/)

The Wishbone-Equipped CB1100

Honda experimented with a variety of alternative front suspension systems while developing the latest Gold Wing before settling on a Hossack/Fior-style arrangement that’s not a million miles from BMW’s Duolever system, as used on the K 1600.

The idea was always to combat the braking dive of the heavy Gold Wing, to reduce the strain on the headstock section of the chassis and to ensure a consistent wheelbase throughout the suspension travel, in turn allowing a shorter wheelbase to be used. And since the idea worked on the Wing, it makes sense the firm is looking at whether other bikes might benefit.

The CB’s engine position required Honda to rethink the lower wishbone’s front pivot point; the engineers moved it forward. (Japanese Patent Office/)

The CB1100 might not be an obvious candidate for wishbone suspension. As the most overtly retro offering in Honda’s range—complete with air-cooled engine and twin rear shocks—its styling and engineering are heavily biased toward a conventional telescopic front suspension system. But perhaps that’s why Honda chose that bike to experiment with wishbone suspension; if it can work on the CB1100, it can probably be made to work almost anywhere.

Although the basic layout is similar to the Gold Wing’s, there are significant changes for the wishbone CB1100. Most importantly, the engine’s position doesn’t allow the lower wishbone’s rear pivot to be mounted as far back as on the Wing. On the Gold Wing, the lower wishbone is mounted further back than the upper one, allowing the lower link to be significantly longer than the upper. To achieve the same ratio of link length, Honda had to rethink the idea for the inline-four CB1100.

RELATED: 2018 Honda Gold Wing Tour vs. BMW K1600B Grand America

With the engine getting in the way of having the lower wishbone’s rear pivot mounted a long way back, Honda’s solution is to move the lower wishbone’s front pivot point forward. That keeps the lower wishbone long relative to the upper one—around twice the length—but means it must reach around the upright above the front wheel bracket extending from the front.

The CB’s bars were also a challenge, as they are positioned directly on top of the fork. Honda’s solution was to use a two-part linkage. (Japanese Patent Office/)

Another change compared to the Gold Wing is the steering system. On the Wing, the bars are mounted much further back, which means Honda could use a simple linkage running parallel with the upper wishbone to connect the bars to the fork. On the CB1100, with the bars mounted directly above the top of the fork, that’s not possible so the firm has opted to use a two-part linkage that concertinas as the suspension compresses. This is the same solution used by BMW for the similar Duolever front end on the K 1600.

RELATED: Honda Adds Super Cub And XR650L To 2020 Lineup

As with all wishbone-style front suspension systems, another advantage is that a single coilover shock can be used to do the springing and damping, which puts the CB1100 seen here in the odd position of having a single front shock and two rear ones—the reverse of a typical modern motorcycle.

At the opposite end of Honda’s range is the Super Cub, a smaller and lighter model and also an unlikely candidate for a wishbone setup. (American Honda Motor Co./)

The Wishbone-Equipped C125 Super Cub

While the theoretical advantages of a wishbone front end remain the same regardless of the type of bike, putting the system on the C125 is testing it at the very opposite end of Honda’s range compared to the Gold Wing currently using the idea.

Not only is the C125 a much smaller machine, but it’s far lighter and features a completely different chassis design with different materials and a different engine layout. That’s probably why it’s been used as another guinea pig for Honda’s experimentation.

In fact, the latest Super Cub is a late adopter of the telescopic fork; earlier iterations like the C50 and C90 used leading-link front suspension instead, but the Hossack-style wishbone setup seen here is a complete departure for the bike.

With a low-mounted single-cylinder engine it doesn’t have the same geometry problem as the CB1100 when it comes to where the rear wishbone pivots are attached. However, here Honda has opted for equal-length wishbones top and bottom.

The argument for using the wishbone front end on the C125 is that it gives more freedom for the position of the bars in relation to the front wheel, allowing a small bike to have a more spacious riding position than if it was fitted with conventional forks.

With the Super Cub’s more favorable geometry, Honda could use the same length wishbone both top and bottom. (Japanese Patent Office/)

Will these ideas lead to production bikes?

Just because a firm files patent applications for an idea doesn’t mean it will make it to production. However, it is a clear indication of what the company’s R&D department is working on.

In the case of the Gold Wing, Honda filed multiple patent applications for several different alternative front suspension systems before settling on the Hossack-style design that reached production. What was clear was that the firm wanted to get away from the limitations of telescopic forks, and it tested several solutions before choosing one that worked best. We’ll keep an eye on Honda’s patents over the coming months to see if the firm continues to develop this idea.

A wishbone setup would be a complete departure for the C125, but it would allow for greater freedom in handlebar positioning. (Japanese Patent Office/)

Interestingly, as Honda moves toward alternative front suspension, BMW—the firm that pursued odd front ends for years with the Telelever and Duolever setups—has moved back toward telescopic forks. These days the majority of BMWs use telescopic forks, with just the Duolever K 1600 and Telelever R 1250 GS staying with alternative front ends.

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