Unleash The Hounds!
BMW let the American moto-press sample the new K1300S in the mountains above Santa Barbara, California, an environment rich with twisty roads upon which to test out the upgrades instilled into the latest Beemer. The unit we rode was a Premium Package model, so we were able to test the complete BMW acronym soup of ESA II, ASC and GSA.
The BMW Paralever single-sided...
The BMW Paralever single-sided swingarm now features a shaft drive with a two-stage damper system to cancel out torque snatch in the driveline that was an issue with the previous K1200S. Continental ContiSport Attack rubber is standard fitment, providing excellent grip with good mileage.
Immediately noticeable is the increased grunt of the new engine. You can literally let the BMW chug down to 1500 rpm in top gear, twist the throttle to the stop, and get nothing but smooth acceleration (the twin counterbalancers quell vibes well) that rapidly builds in ferocity. There's excellent power on tap as low as 4000 rpm, enabling you to run a gear higher in many situations that would tax the previous powerplant. Highway overtaking is now accomplished with ease and quickness.
However, it's the boost in midrange and top-end that will really get your attention. While the K1200S couldn't exactly be labeled a weakling, even when compared against the old Hayabusa or ZX-12R, it just didn't have the same hair-on-fire, peel-your-face-back acceleration at higher speeds (and when compared against the latest Hayabusa or ZX-14 it paled even more). Now when you grab a handful of throttle, the acceleration has that same unrelenting locomotive-on-nitrous feel that continues well into triple digit territory. And yet the powerband is much more linear as well; there's none of the power spikes at 6500 and 8000 rpm that the old engine had.
Throttle response—especially off trailing throttle entering a corner—is silky smooth, with none of the jerkiness that plagued its predecessor, allowing earlier and stronger drives off corners. There was one small hiccup, however: on trailing throttle between 5000-5500 rpm, there was a distinct flat-spot/hesitation when you got back on the gas. It was much worse in the higher gears, mostly because it was easier for the engine to pull out of it in the lower cogs. It definitely felt like a lean fueling issue, and while not alarming, it became bothersome when running through a series of medium speed corners where you often end up accelerating from that rpm.
Our test unit was fitted with...
Our test unit was fitted with the optional GSA (Gear Shift Assist) powershifter. The system uses a Hall-effect switch to allow full-throttle upshifts. We found its delay time to be a little excessive, and a bit of overkill on a torquey bike like the K1300S.
The traction control is non-adjustable, and as such, its interrupt strength and threshold are both fairly conservative. While not overly obtrusive (unless you try to pull a wheelie, which it swiftly kills off in midstride, resulting in the front end slamming back to earth), you can definitely feel its electronic hand slowing you down when you start trying to push the limits of the OE fitment ContiSport Attack rubber. Like the ABS, it can be turned off if so desired.
The second-generation ESA II differs from the previous version by its ability to not only adjust spring preload and damping on the fly, but also spring rate if required. By using a movable internal sleeve that adjusts how much support is given to an elastogran (a thermoplastic polyurethane elastomer) sleeve at the end of the spring, the system in a roundabout way adjusts the spring length, thereby changing spring rate. We actually grew to like the first ESA system on the K1200S, and the same is true of the ESA II on the K1300S; it's undeniably convenient to be able to switch the suspension from twisty road firm to highway plush at the push of a button. We ran the setting on standard with a single rider when corner carving, as the sport settings were too firm in our opinion.
A powershifter is a nice idea on a bike that requires a lot of shifting like a high-strung 600, but on a torquey, wide-powerband beast like the K1300S, the GSA is kind of overkill. We also found the unit's delay time to be too long, with the shifts often taking longer than a crisp non-clutch upshift would.