The 2015 production RM-Z450s from Suzuki carry a ‘Holeshot Assist Control’ system. The set-up is essentially a form of traction control that manipulates the ignition timing to allow for more effective starts in hard or slippery conditions.
The electronics reset after a small delay – anything from 1.2 seconds to 4.5 – or by hitting fourth gear or closing the gas. The device is engaged by pushing a small clear button on the handlebar.
As with fuel injection on their flagship four-stroke back in 2005, Suzuki are the first to release a stock motorcycle from factory floors with this technical addition and it comes directly from work achieved by the works MXGP Rockstar Energy Suzuki team with riders Clement Desalle and Kevin Strijbos; both currently second and fourth in the 2014 standings.
The effectiveness of ‘HAC’ has yet to be fully tested for the average rider and racer but the Suzuki MXGP crew are still developing the technology and don’t particularly like speaking about their delicate findings. “It is something we have been working on for two years but also a sensitive area for us,” remarked Team Principal Sylvain Geboers. “It involves the electronics and some assistance for the riders at the start but it is a very complicated addition to the bike and set-up.”
Desalle and Strijbos have been a constant presence at the start of MXGP motos through the nine Grands Prix this season so the mechanism is clearly having some positive effect at the sharp end. We asked Strijbos for a bit more analysis through his Grand Prix tests. “There are so many settings with that,” he said. “We can have more or less power, more or less traction. I usually have the most powerful setting, so that it doesn’t drop as soon as I hit the gas. My team-mate has something different from what I hear.”
“At most of the tracks it is the same spec but we can change it when we want,” he added. “I engage it when the fifteen second board goes up and I’m told it will last for the crucial time that we need. It is cool that we have the light also to know it is activated.”
The advancement of electronics was seen in MXGP more than two years ago when Italian company GET introduced their GPA (GET Power Assistance); a form of traction control that was pioneered with factory Yamaha and Honda teams. It is now almost a standard part of most 450cc set-ups but Suzuki – who rely on GET material for data acquisition – is one crew continuing to push the possibilities of engine management. “I think most factory riders have some kind of mechanism or device from what I can see so why not us?” concludes Strijbos.
Further use of electronics in MXGP sees Jeremy Van Horebeek’s prototype Yamaha carrying an electric start and rumours that the factory Hondas of Max Nagl and Evgeny Bobryshev will also soon remove the kickstarter from their CRF450Rs.