One of the best things that happened in the 70s was the Honda CB750. Known as the first superbike, the inline-4 powered CB750 was magical and set the foundation for the superbikes in the years to come. But Honda did another experiment on this venerable platform. A twist-and-go version of the CB750. It was called the CB750A Hondamatic and the magic of that motorcycle may be ready to make a modern comeback.



The reason why Honda came up with the CB750A Hondamatic in the first place was that they wanted to combine the power of a superbike and the ease of use of a scooter. Not the easiest things to do, to be honest. But Honda did succeed... somewhat. While the bike worked as intended, the power loss was too great for the enthusiasts and then power itself too great for easygoing riders.

So, it was not the idea that did not work, it was just that the execution did not come about easily. But now, Honda seems to have dusted off the old design sheet in hopes of recreating the magic. And the lab rat for this experiment is none other than the Honda CB1100, the direct descendant of the CB750.

Again, the intent is the same; to amalgamate the performance of a sportsbike with the ease-of-riding of a scooter to make a motorcycle that is not only enjoyable but easy to enjoy as well. In the past, Honda achieved that by replacing the clutch with a torque converter, something widely used by automatic cars.

The torque converter was also combined with a 2-speed gearbox. It allowed the rider to select high or low ratio. The above will be controlled by the riders' conventional foot panel. The problem with the setup was almost blunt power and performance. The first superbike, CB750, just didn't feel like one with that setup.



The new design, according to the patents seemingly, has a similar set of controls. A foot-operated gear shifter is there but the clutch is missing. The idea to retain the 6-speed unit to make sure that the performance remains the same. The work of the clutch is taken care of by a computer-controlled, electro-hydraulic actuator, mounted just above the engine which replaces the conventional lever.

The clutch reservoir is conventionally mounted on the bars to make checking and filling easy. An array of inputs including sensors for speed, revs, gear position and throttle position are allied to a sensor that monitors pressure on the gear lever.

The information obtained is then used by the ECU to cut the ignition during upshifts, blip the throttle on downshifts and modulate the clutch when starting and stopping. Quite a bit like a modern up-and-down quickshifter. The only difference is the lack of a clutch.

One major difference between the Hondmatic clutch and the conventional clutch is that while the latter's default position is the engaged position, the Hondamatic clutch defaults to a disengaged position.

Quite a departure from convention but hey, until it works, it's alright. More importantly, it makes sure that the drive is disconnected if there's a loss of hydraulic pressure or electronic failure. A highly unlikely event, but quite possible.

A solenoid-operated valve closes the hydraulic system once the clutch is engaged during normal use to save the actuator from having to constantly maintain hydraulic pressure.

Another thing, and a very important one, is that the system is a simple one and while the patent shows a Honda CB1100, it can actually be installed on any motorcycle. A few advantages of the Hondamatic are; the simplicity of a scooter with the performance of a superbike, does not require creating a whole new gearbox or reengineering one; and finally, it is the relative cost of manufacturing.

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