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Engineers have tried and failed for decades to build motorcycles with automatic transmissions. Honda finally gets it right with the new DN-01 “sports cruiser” bike. Conventional automatic transmissions, like those in cars, lag when you hit the throttle and can throw a bike off balance during turns. Honda’s HFT (for Human Friendly Transmission) responds to the throttle instantly by using hydraulic pumps instead of standard gears.

The HFT offers a range of gear ratios similar to a conventional six-speed manual, and it has about the same weight and dimensions. The motorcycle goes on sale in Japan this year, though a price has not been set. Honda hasn’t yet decided if America’s weekend rebels will get their own auto-shifting bike.

Launch the gallery to see how Honda’s truly fluid transmission works.

Honda DN-01 Transmission

Honda DN-01 Transmission (step one)

1. The engine cranks a pump that turns both the drive shaft and a tilted metal disk [A].
2. As the disk spins, it depresses a circular set of pistons [B] around the shaft.
3. The pistons eject high-pressure fluid that travels through a chamber [C] and pushes out a second set of pistons [D].
4. Those pistons press a second tilted disk [E], causing it to spin and transmit extra torque (leverage) to the drive shaft.

Honda DN-01 Transmission (step two)

5. A motor adjusts the angle of the second disk . A lot of tilt provides the high torque found in low gear [F]. Less tilt offers lower torque but more speed, like a high gear.

Honda DN-01 Transmission (step three)

6. When the disk isn’t tilted [G], the second set of pistons shuts off to save power, and the pump alone turns the shaft and rear wheel.

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