Words: Andy Wigan | Photos: Andy Wigan, M. Campelli, S. Romero
If you’ve sat aboard a four-stroke KTM or Husqvarna in the last couple of years, then you will have noticed a new-looking switchblock mounted next to the bike’s clutch perch: a map-selector switch that, for the first time ever on a production dirt bike, incorporates a traction control function. And if you’ve activated that “TC” button and gone for a ride, then it doesn’t take long to realise just how effectively the system works.
But where did this TC technology come from? How exactly does it work? What are its pros and cons? What’s it actually feel like to ride a bike with traction control? And will these two brands’ two-stroke models adopt the technology in the near future? After collating feedback from owners, dealers, racers and technicians, we reflect on the emergence of what appears to be widely regarded as the most cost-effective traction aid that production enduro bikes have ever seen.
Here are the lucky 11 most commonly asked questions about this new technology:
1. WHICH MODELS DO & DON’T GET TRACTION CONTROL?
At this stage, traction control is only available for four-stroke models.
2. ISN’T TRACTION CONTROL ILLEGAL ON DIRT BIKES?
Yes, it is. But the rulebook used by most racing federations around the world defines “traction control” as a device that uses a sensor on the rear wheel. As the ‘traction control’ technology found on KTM and Husqvarnas doesn’t use any wheel sensors or GPS devices whatsoever, it is 100% legal.
3. HOW EXACTLY DOES THIS TC SYSTEM WORK?
The Traction Control (TC) function is integrated into the bikes’ ECUs, and activated by an all-new, bar-mounted map-selector switch. Instead of using a sensor on the rear wheel, the KTM/Husqvarna TC system simply analyses throttle inputs against sudden increases in RPM, and retards the power accordingly (via changes to the map’s ignition timing, not fuel) to maximise rear wheel traction.
4. WAS THIS SYSTEM ADAPTED FROM GET’s GPA (GET POWER ASSIST) TECHNOLOGY?
Not according to one of KTM’s key engine development Project Leaders over the past decade Michael Viertlmayr. “It’s true that several race teams in Australia, Europe and America – including KTM’s – have used GET ECUs and the company’s GPA technology for a few years now, but we developed our TC system in-house,” Viertlmayr explains. “When we first tested it three years ago, we were initially very skeptical about it. We were also unsure of how off-road guys would embrace the idea of more electronics. But after the first two times we tried it, we quickly changed our attitude. Not only did it immediately prove to work very effectively, but it was also a simple system because you don’t need any additional wheel or gyroscopic sensors. In basic terms, the ECU is able to determine when, for a given throttle setting, the rear wheel is spinning up too fast. In those instances, it simply retards the power. And we were able to adapt it to each specific gear. In terrain where you have only small patches of traction in between loose rocks or slippery mud, the full potential of the traction control is even more evident,” Viertlmayr went on to say.
5. CAN THE TC SYSTEM’S ‘SENSITIVITY’ BE ADJUSTED?
No. In the interests of keeping the system simple, affordable and effective, it’s not adjustable. But because the TC function applies to both Map 1 (standard) and Map 2 (aggressive), you effectively get four maps from the one Map-Selector Switch. And intelligently, the map and TC settings are retained, even when you stop (or stall) the bike.
6. SO WHAT DOES IT FEEL LIKE? ARE YOU CONSTANTLY AWARE OF THE TC WHEN RIDING?
It’s nothing like the TC systems used on older-style, large adventure bikes (where there’s an audible, stuttery, hit-the-rev-limiter type of interruption to the power delivery), or even the more sophisticated TC system used on KTM’s new adventure models, where the ECU controls the butterfly angle to limit power. The TC system used on KTM’s competition dirt bikes is more of a subtle de-tuning of the power delivery, but only when absolutely required. The system is calibrated so that you can still get the rear wheel spinning-up and the bike’s rear-end stepped out as sideways as you like when the terrain offers consistent grip levels. But in really slick conditions – such as loose rock or patches of wet, soapy clay – it takes the emphasis off the need for super-precise throttle control, and it helps keep the rear wheel hooking up. That results in a bike that consistently tracks straighter, which makes it easier and safer to ride – especially as the rider becomes fatigued.
7. ISN’T TC ONLY REALLY USEFUL FOR LARGE-CAPACITY BIKES WHOSE HORSEPOWER IS HARDER TO GET TO THE GROUND?
Well, conventional wisdom would expect that to be the case. But the overwhelming feedback – from the product development teams, Australian dealers, owners and media outlets – all seems to suggest that this TC system is also proving very effective on the smaller-capacity machines, mainly because they spend more of the time higher in the rev range and are equally inclined to break traction suddenly when the rear wheel hits an unexpectedly slippery patch of terra firma.
8. IS THE MAP-SELECTOR SWITCH ITSELF EASY TO USE?
Thankfully, yes. In fact, it’s dummy-proof. Unlike the previously fiddly little Map-Selector Switch, the all-new rubberised, bar-mounted switch is bigger and super-easy to use on-the-fly. It has different-coloured lights that illuminate for each setting (white and green lights for Maps 1 and 2, respectively, and an orange light to indicate the TC is activated) – meaning the switch confirms at a glance exactly what settings you’ve selected with your left thumb.
9. SHOULD THE TC BE TURNED OFF IN CERTAIN CONDITIONS?
Again, feedback across the board has suggested there is really no downside to leaving the TC system constantly engaged, whether you’re using Map 1 or 2 – because it only takes the edge off the power delivery when it’s absolutely necessary. That said, in deep, boggy sand, where you can happily use all the wheelspin you can get, there’s little point in activating the TC. In fact, in these conditions, it’s better to deactivate the system to access the engine’s full horsepower.
10. DOES THE TC TECHNOLOGY MAKE THESE FOUR-STROKES’ ENGINES MORE VERSATILE?
Absolutely. The introduction of the TC system has meant that KTM’s and Husky’s design teams have been able to better harness the gains in the engines’ torque and outright power, which ensures the bikes remain easy to ride. The TC function has also meant that mapping changes are now simpler and more intuitive. In the past, many owners (particularly with the larger-capacity models) would use Map 2 as a softer, traction map (and this would require them to first adjust the 10-position dial on the airbox-mounted switch!). In other words, the TC function has allowed owners to access a broader and more versatile range of maps, with one bar-mounted switch letting them toggle between them.
11. WILL TRACTION CONTROL SOON APPEAR ON KTM’s AND HUSQVARNA’S TWO-STROKE MODELS?
Yes, but not until KTM’s/Husky’s two-stroke models move to fuel injection, according to KTM Australia’s Technical Services Manager, Rob Twyerould. “The reason for that,” explains Twyerould, “ is that for fuel injection, we run an ECU with much higher processing power and the ability to incorporate those additional features. As an ECU has control over the air/fuel mixture and ignition settings of a bike’s engine, it can be used to get the traction control functioning properly. With a carburetted bike, however, the CDI it uses may not have the processing power to run a traction control system. Plus, because the CDI doesn’t have any control over the engine’s air/fuel mixture, you’re at the mercy of the owner having the bike jetted correctly to have the traction control working correctly. Even though TC systems only affect the ignition timing, not the mixture, the way the engine runs overall will have an impact on how effective the traction control system will be. So, once KTM and Husqvarna move to fuel injection on their two-strokes models, it’s much more likely for traction control to be incorporated into these models,” Twyerould went on to say.