Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/789906
VOL. 54 ISSUE 7 FEBRUARY 22, 2017 P73 But there's one part of the equation we're yet to talk about. ELECTRONICS FOR DAYS This area is the main talking point of the new CBR1000RR range. Criticized in the past for having no more electronics than fuel injection and the company's heavy Combined ABS system, the CBR now has everything the others have and more, but it's not as straightforward as slapping on a traction control system and hoping for the best. Oh no. Honda has developed a whole new electronics package for the CBR based off the RC213V-S, which, in turn, is developed from Repsol Honda in MotoGP. Yes, the CBR does use the Bosch IMU, but it uses it differently than Yamaha or Ducati, for example. Honda's electronics combine traction and wheelie control func- tions. That is an ultra-important point because since the Bosch IMU was released, the manu- facturers that used it on super- bikes separated the traction and wheelie parameters, allowing you to vary them independently. Honda chose to combine them, and herein lies an issue. Under the acronym HSTC (Honda Selectable Torque Con- trol), the system calculates the throttle input, lean angle, and the rate of slip from the rear wheel to determine how much gas you're allowed to have and ultimately, how hard you can drive out of a corner. There are nine different levels of traction control, yet the linked wheelie control has three modes: Level 1 (aimed at track riding) provides a reduced wheel- ie control input in throttle modes one to three; Level 2 wheelie (for fast canyon riding) provides more wheelie control in throttle levels four to six; and Level 3 wheelie control (for normal street rid- ing) allows next to no lift at all in throttle modes seven to nine. Portimao compounds issues because you can spin the rear wheel like mad and wheelie into next week thanks to the undu- lations of a racetrack situated between three separate canyons. The entry onto Portimao's front straight is three long, separate right-hand apexes, all while going downhill, leading to a massive hump onto the straight proper. The wheelie control at this section of the track is an issue because when the front wheel comes up, it comes up hard—the HSTC electronics allow for a big, short distance wheelie, but then cuts the ignition viciously, slamming the front wheel to the ground. The problem here is not that the wheelie was cut. It is the fact that the system uses only front and rear wheel speed to detect if a wheelie has occurred, rather than the front and rear chassis pitch rate calculated by the IMU. On something like a Yamaha YZF-R1, the wheelie control can be programed in to allow you to keep the throttle pinned and have power still being transmitted to the rear wheel, with minimal drive lost as the system slowly brings the front wheel back to earth. On the CBR on Portimao's front straight, at 140 mph it takes the best part of two seconds before I'm allowed to have any drive after the wheelie comes. This is due to the time it takes for the front and rear wheel speed sensors to sync back up, and the ECU shutting the throttle bod- ies. Nothing is happening at the twistgrip, only the traction control light flickering on the dash until it (L-R) See that little orange "T" circled in the top left corner of the dash? That's the traction control light coming on at over 150 mph. The CBR wasn't spinning, but it wasn't driving, either, as I waited for the front and rear wheel speed sensors to sync up and the light to disappear. Just like the old bike— the base model CBR comes with Showa's Big Piston Fork.