BMW go clutchless with Automated Shift Assistant prototype fitted to an R1300GS

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BMW are looking to revolutionise the way we change gear by launching a new automatic transmission, dubbed Automated Shift Assistant (ASA) offering both a manual and full auto setting.

The technology was revealed to MCN at an exclusive event at the BMW Enduro Park Hechlingen, near Munich last week, with the brand running a live demonstration of the technology, in pre-production form, on a BMW R1300GS adventure bike.

BMW say they’ve been working on the project for five years, with the aim of evolving their up/down quickshifter systems into a fully automatic transmission, with a ‘manual’ mode where the rider selects their own gears.

BMW ASA diagram within an R1300GS boxer twin engine

In both modes, the clutch operation is completely automated, with no clutch lever on the handlebars. There’s still a foot gear lever, though it’s merely an electric ‘switch’ with no mechanical function.

The whole ASA system is essentially a computer-controlled conventional motorcycle transmission, with electrical actuators working the clutch to pull away and stop and shifting the gear ratios.

Meanwhile, the Transmission Control Unit adjusts the gear shifting parameters according to riding style, and which riding mode the bike is in – so an Off Road mode would have different gear change characteristics from Rain or Sport modes.

Hand on grip of BMW R1300GS ASA prototype

We asked Project Manager, Reiner Fings about the lack of a clutch lever, and if the engineers had considered fitting an electronic ‘clutch by wire’ lever to give the rider an override, as with the new Honda E-clutch system (which can now be fitted to the firm’s CB650R and CBR650R).

“We had an electronic clutch lever when we started development,” said Fings. “But the more we rode, it made no sense, so we threw it away.”

What about the foot gear lever? Could BMW have used an electrical ‘paddle’ shift on the handlebars instead? “We decided to have a gear lever, so it stays the way you ride a motorbike now. Maybe one day there might be paddles; there’s no technical reason we couldn’t have that.”

BMW R1300GS ASA prototype switchgear

Watching Reiner Fings ride the ASA-equipped bike around the Enduro Park, there was nothing unusual to see or hear. The bike pulled away, changed gear, and came to a stop just like any other R1300GS. But when Fings waved his left arm and leg in the air as he rode past, it was clear something weird was going on.

In practical terms, the new setup adds around 2.1kg of mass to the existing setup and will cost around €1,000/£850 extra as a factory-fitted option.

The ASA can’t be bump-started if your battery runs flat, but it does have an additional anti-theft feature. Turn the ignition off with the bike in ‘Park’ and the transmission is locked in gear, with no way to change into neutral without the ignition key. So thieves won’t be able to wheel the bike away, even if they overcome the steering lock.

BMW R1300GS ASA prototype ridden off-road

BMW were a little vague on when exactly we’d see this new gearbox, and on what bikes. But the development team suggested it will definitely be released in the second half of 2024, on a 1300 Boxer-powered machine first, with other fitments possible later on.

How does BMW ASA work?

Get a shift on: The foot-operated gear lever is connected to a small shaft inside the engine with a sensor to detect when the rider moves it up or down. There’s no mechanical link at all.

BMW R1300GS ASA prototype engine diagram

Clutch work: The hydraulic clutch actuator uses a unique spiral-groove gear to move a triangular swivel arm that operates the master cylinder. The gear has a spiral groove cut into its face, which engages with a pin on one point of the swivel arm.

A motor turns the spiral gear and as the pin follows the groove, it moves inwards, rotating the swivel arm on its pivot. The third point of the swivel arm pushes onto the clutch master cylinder, disengaging the clutch as it moves in, just like when you pull a conventional clutch lever on the bars.

Make a selection: BMW have used a new mechanism to turn the gear shift drum quickly and precisely. It’s called a Geneva Drive (it was first used in Swiss watch mechanisms) or a Maltese Cross gear, and converts constant rotation into an intermittent, precisely controlled rotary movement.

BMW R1300GS ASA prototype presentation diagram

There’s a normal-looking pair of gears, with an electric motor driving the smaller gear. The larger gear has a raised flange with a cut-out, and a small pin.

This pin engages in a third Maltese Cross ‘gear’, which has a complex shape, made up of six slots and six arms with curved ends. The pin on the middle gear fits into each slot in turn, and as the gears move, it rotates the Maltese Cross gear exactly 60 degrees (360/6) then stops.

The curved end of each arm locates on the raised flange as the gears turn, preventing the Maltese Cross gear turning any further until the pin engages in the next slot.

Alan Dowds

By Alan Dowds