Push-button electronic system drops the clutch for automatic shifting
Some manufacturers like Honda, Yamaha, Aprilia and Can-Am offer bikes and trikes that are either semi- or fully-automatic, but converting a manual shifting bike to something resembling an automatic has not been easy. Biperformance Development Corporation (BDC) believes its ShiftFX Electronic Shift Transmission (EST) could change that.
The ShiftFX EST is the result of over a decade of work BDC has put into developing kits that initially added only semi-automatic features to a motorcycle. The company's latest iteration claims to offer the rider the ability to not only choose that mode, but a fully automatic one as well, while also maintaining a fully working clutch should it be necessary to use one for emergency or poor traction situations.
In semi-automatic mode, the ShiftFX is said to work similar to the way a paddle shifter works in a sports car. But in this case, the rider pushes a green button to upshift, a red one to downshift, and a black one for neutral. Those buttons are mounted near the left hand grip for easy access, with gear changes made in as little as 30 ms.
A separate control mechanism allows the rider to choose between automatic, semi-automatic or neutral. Once in automatic mode, the bike operates just as you would expect with clutchless and buttonless shifting up and down the gear range.
The ShiftFX EST consists of three main components: Active Clutch, which allows electro-hydraulic control of the clutch; a high-speed DC motor and fixed gear reducer; and a transmission control unit (TCU) that can be programmed to change the shifting characteristics of both the semi-automatic or automatic mode.
The Active Clutch is the critical component. It consists of a master cylinder operated by a memory-shape-alloy actuator inserted into the clutch hydraulic system to provide electronic control of the clutch. An isolation valve in the system is what allows the rider to use the regular clutch to manually override the system.
The ShiftFX gear control system swaps the shift lever and ratcheting mechanism found in a standard gearbox with a patented high-speed DC motor and gear reduction set. This eliminates the need to downshift through multiple gears and makes it possible to go from any gear to another without shifting.
BDC says the electronic shift transmission system adds about 2 kg (4.4 lb) to the overall weight of a bike, and can be integrated by the OEM onto any motorcycle engine that uses a transmission shift drum.
The fully programmable TCU gives riders the ability to set shifting characteristics based on load, speed, throttle and other parameters. It connects to the engine's ECU (electronic control unit) and adds additional controls over engine braking and engine speeds during down shifts.
It appears that the ShiftFX EST will only be available through OEM manufacturers since the housing for the gear control units has to be made to fit specific engine and transmission drum combinations. So unless you're a DIYer with some serious machining and mechanical capability, installation of this modification is going to have be done by a qualified OEM mechanic.
BDC says pricing for the conversion is likely to be similar to the cost to upgrade a motorcycle from a manual braking system to ABS (about US $1,000 or more), but that could change depending on the volume of ShiftFX systems sold.
So who would buy this system? While being able to turn almost any bike into an automatic seems like an appealing idea, serious motorcyclists aren't likely to jump at the chance – or the extra expense. It may attract beginning riders intimidated by the idea of using a clutch and shifter, but they are probably more likely to opt for a bike or scooter with a CVT. There is one market where this system would definitely find traction, though – disabled riders who are unable to operate a gear shifter.
Check out the video to hear a bike fitted with the ShiftFX EST go through its gears.