Automated Manual Transmission (AMT)
By Ben Purvis
The race to automate clutch functions continues, with KTM the latest to join the revolution. The company's answer to HONDA's 'DCT', the BMW 'ASA' and Yamaha's 'Y-AMT' is simply called Automated Manual Transmission (AMT) - which will first be seen on the 1390 Super Adventure S Evo.
KTM uses just one electromechanical servo to turn the shift drum they combine it with a purely mechanical centrifugal clutch that disengages when the bike comes to a halt, automatically re-engaging when the throttle opens - using the same tech that's been around for decades on scooters.
It's a set-up that should be lighter and less costly than its rivals' designs. On the move, KTM uses the same tech already implemented on quickshifters to cut ignition during upshifts and blip the throttle on downshifts, timing it with the servo-operated movement of the shift drum to make for gearchanges that take only 50 milliseconds.
The design has also required a rethink of the transmission because the centrifugal clutch defaults to a disengaged state, the opposite of a conventional clutch, and that means it's impossible to leave the bike parked in gear. That would cause a problem when parking on slopes, so KTM has introduced a 'Park' setting to the gearbox that engages a locking pawl to stop the gearbox from being able to turn.
Like others, the KTM system allows multiple modes. It can change gears completely automatically, with three options for shift points and aggression - Comfort, Street or Sport. In these modes it will automatically kickdown if you open the throttle fast, and a kickdown can also be prompted by rapidly closing the throttle, then opening it again.
There are also manual controls via paddles on the left bar - these will always work, even in fully auto mode, if you want to override the bike's gear choice - and an additional foot control that mimics a conventional shifter if you prefer a more traditional feel. Because it's all electronic, you can even switch the foot shifter to a race-style, upside-down shift pattern simply by altering your preferences on the dashboard.
The system also means KTM hasn't felt the need to stick to the conventional one-down, five-up shift pattern. That design is intended to make sure you can change down to first without accidentally ending up in neutral - something that isn't an issue with an electronically controlled gearbox. Instead, the KTM box uses a pattern of P-N-1-2-3-4-5-6, with park and neutral only selectable when the bike is stationary.
The AMT transmission opens up new opportunities when combined with the Bosch radar-guided cruise control that's already optional on some KTMs. While the original generation of that system, when active, could keep pace with traffic ahead automatically at speed, when paired with the automatic transmission, it allows the radar to control the bike's speed all the way to a complete standstill.
Initially, the system is being applied to KTM's large LC8 V-twin engines in '1390' form, and it's expected to be offered on several models in the coming months.
