Originally Posted by
RadDog
You would not have to back off the wattage while shifting, you could just power/grind right through with no loss in speed or momentum. It would give you a massive advantage.
For people unfamiliar with the technology, Doppelkuppling (PDK) functions with dual clutches. While one clutch disengages, the other one engages. With a car traditional clutches require you to back off the gas while disengaging from one gear and re-engaging with the next gear. The car looses a tremendous amount of power (temporarily) and momentum. The PDK does not. That is why cars with 500 hp and PDK actually accelerate faster than a traditional 6 speed clutch on a 600 hp car.
Lets apply this to bikes: You have to back off your peddle force every time you shift. Imagine not having to do so, instead powering through your peddle stroke with 100% force while simultaneously changing gears.
Now THAT would be pretty freakin' cool.
I’m a dyed-in-the-wool manual driver, but a day spent with a dual-clutch transmission (rental Hyundai Veloster) had me seriously considering shifting (sorry!) to the dark side - shifting, auto or by paddle, was unreal. The momentum lost as the motor is disconnected from the drivetrain during gear change - either auto or manual - is circumvented by having the “next” gear tee’d up and ready to engage instantaneously.
However, not sure about having to ease off when shifting on the bike. I do this under a few specific circumstances, namely dropping from large to small chainring (if the chain is under too much tension, it can defeat the relatively weedy spring of the FD), and when shifting to a larger sprocket when climbing out of the saddle (I unweight the pedals momentarily by leaning forward onto the bars just as the chain shifts). Otherwise, I’m not aware of any easing off when shifting either up or down.