First Look: KTM automatic gearbox released

Austrian firm, KTM, shows off yet another automatic gearbox design

Automatic bikes are a bit like buses – there are none for ages, then you get four at once. And they’re also a bit heavy, slow, expensive, and can carry 76 passengers, no standing on the top deck.

KTM Automatic gearbox

Okay, they’re not really much like buses. But we have seen a few of them this year: Honda’s E-clutch, BMW’s ASA automated shift assistant, and Yamaha’s AMT automated manual transmission. And now we have info on another AMT, this time from Austrian bike maker KTM, which has announced the new setup for 2025.

And it’s, perhaps surprisingly, quite different from the other systems. Where the BMW, Yamaha and Honda setups have electronic actuators to operate the wet multi-plate clutches, KTM has gone for an alternative mechanical system, with a centrifugal clutch operation.

KTM automatic gearbox

These have been around for a while now: inside the clutch drum are weighted rollers (or ball bearings, KTM’s not clear in the release which). And as the clutch spins faster when you open the throttle and engine revs rise, these balls or rollers are flung out by the centrifugal (centripetal) force.

As they move out, they push on ramps or sloped faces on the clutch internals, pushing the clutch plates together and locking it up, to deliver drive to the gearbox input shaft. So where a normal clutch is usually clamped shut with springs, and you disengage it with the clutch lever, the centrifugal unit is normally disengaged, but as the engine revs rise, it automatically engages.

The most recent firm to use a centrifugal clutch on a big bike has been MV Agusta – and while we’re not certain, it seems possible that the recent KTM takeover of Agusta might have led to some technology sharing here.

Away from the clutch, the gearbox is largely conventional, though it has neutral below first gear in the shift pattern rather than between first and second gears, and it also has a ‘P’ park position below neutral, which locks the gearbox as you get on an automatic car. That will work as an extra anti-theft device, preventing the bike being pushed away, as well as helping when parking on hills etc.

The gear selector drum has its own electric actuator, controlled by a transmission ECU, and it’s this that lets KTM have both an automatic and manual mode on the bike.

KTM automatic gearbox

Once you’ve pulled away with the centrifugal clutch, the ECU takes over in auto mode, changing up and down gears as needed, with a conventional quickshifter setup cutting the throttle for up shifts and auto-blipping on downshifts, just like on manual gearboxes.

The AMT also has a manual mode of course, and here the rider can either change gears with the foot lever, as on a normal bike, or use a bar-mounted paddle switch to click up and down the ratios using the electronic shifter mechanism.

The first bike to feature the new KTM AMT will presumably be the 1390 Super Adventure dual sports machine – that was the bike which the firm showed off the tech on with enduro rider Johnny Aubert, and it’s also the model these pictures come from. And the Austrian outfit says the auto box will be rolled out on other premium models for 2025 and beyond. More as we get it!