The Control Freak — or Letting Go of the Clutch Lever: Honda’s Dual Clutch Transmission

I spent the better part of two decades working to become a Jedi Master of Motorcycle transmissions. Preloading shifters, feathering dry clutch levers, matching RPMS, optimizing drift and drive entering and leaving corners – seeking the smooth.

All of that, apparently, counts for nothing, now. The robots have come, and they are our masters.

When Honda asked me to evaluate their Dual Clutch Transmission (DCT), I’ll admit that I was skeptical. Operating the gearbox and the focus it demands is one of the pleasures of proper motorcycle operation, and one I from which I took great pride.

Still, there are times when that focus can become a chore – like while stuck in congested traffic during a commute or worse still, hitting a huge construction backup or accident delay during a long tour. Sadly, we all don’t get younger, and clutch hands can and do wear out, and what do you do then? With The Gold Wing’s DCT offering an F1 style manual paddle shifted mode, one has the option of doing the shifting if you want to, and not having to if you don’t want to.

The DCT is an outgrowth of Honda’s 2- and 4-wheel racing programs. DCT is technically a manual gearbox, but a manual gearbox where the forks and selectors are operated by electronics and hydraulics. If that was the design’s only trick, that would be enough, but the real genius is the transmission’s dual clutches. The way the gearbox is constructed, the first clutch controls 1st, 3rd, 5th and 7th gear, while the second clutch controls engagement of 2nd, 4th and 6th gear.

Honda 7 Speed Dual Clutch Transmission

To effect gear changes, the transmission controls have already engaged the next gear during an upshift, and simply disengages the first gear clutch while simultaneously engaging the second gear clutch. The bike is never out of gear, for even a millisecond, and there is never any break in forward momentum while accelerating. Same thing happens while decelerating, only backwards.

You can’t do that, no matter how much The Force may be with you, Mr. Jedi Motorcycle Transmission Master, and your back seat passenger, who has smacked helmets with you an infinite number of times, knows it too.

Thumb the Gold Wing into ‘Sport’ mode, with the DCT in automatic, and find a long empty stretch of rural highway. Roll the throttle wide open and the DCT will simply amaze you with a series of seamless, peak power shifts that keep the bike hooked up and hauling, front tire skimming the pavement through the shifts into 2nd, 3rd, 4th… In its selected environment, and demonstrating clear intent and aggression at the throttle, the DCT is simply amazing.

Like all things managed by software, get tentative, though, and things could be better. In the bike’s default ‘Tour’ mode, automatic shift decisions always carry too few rpms. The bike always has the torque to bull through it, but it feels like emergency acceleration is just out of reach (although with automated downshifts, it really isn’t), and the engine feels less than smooth when it clearly is at higher rpms.

‘Sport’ mode is better with shift points – holding the engine in the middle of its output and making decisions which more closely mimic my own – although after hard acceleration it tends to hold onto a gear way too long when the throttle goes neutral to closed. Both modes will occasionally snap off a downshift just after corner entry if you’re coming in off the gas, which was a behavior which had me saying non-G-rated words.

Fortunately, the system has the ability – even when in automatic mode – to accept user overrides from the paddles, so once I got in the habit of snapping off a downshift before I started corner entry all was right in Wing World.

Where the system really shines is in ‘Manual’ mode, though. With all of the shift decisions being made by a skilled rider, the DCT is magic. The Robot is faster than you, he’s smoother than you, and he never misses a shift. On a flowing two or four lane highway the system is responsive, smooth and powerful – taking repeated seconds out of shifting in ways you could have never appreciated until they were gone.

The Robots may be here, but the humans still have a thing or two to show them.

 

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This article was originally published in the September/October 2018 edition of Motorcycle Times.

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