Went from '08 R1200R to the '09 K1300S. The K is superior to the R except it's not as flickable due to extra weight. Absolutely no engine heat issues with the K, and though I've preferred nakeds up to then, the full fairing produces a much more comfortable (protection from weather elements) particularly in winter. I ride year 'round; will occasionally hit the 20's at night in worst of winter and that requires electric jacket liner.
The R12 without ESA has a more compliant ride than the K bike's ESA set to "comfortable" and still allows spirited, controlled rides on backroads at speed. If I were to order again, I would not option ESA on any BMW... just ride the std OEM's until they're gone then replace with Ohlins.
I would consider returning to an R12R when the next ones come out with the twin OHC cyl head already in the late RT's and GS's, by way of the HP2. Problem is again.... no lower fairing for protection in rain/cold and no quickshifter option, which is awesome addition. I ride pretty aggressively (for my age group) so I'd do similar mods as before on the '08 to boost power.
I only ride solo, but can tell you the R is better for 2-up since the driver sits upgright. The K averages a true 50mpg which was just about what the R did. Service is far more expensive on K when it comes to valve adjustment/plug installs, but you can easily go 24K (18K per manual) before you need to even consider unless you track the bike often. I'm already approaching 25K and the valvetrain is no noisier than when new. Clutch is still right on. The ESA shocks are OK, but I'd really prefer new ones soon and considering pulling the ESA versions and just installing std Ohlins (far cheaper and rebuildable). The K bike only has a couple areas where you might feel some vibration, but it's never annoying... just like the twin R that pulses when you accelerate from low speeds. The torque on the K is far superior than the R's. I had a fuel module and full Remus exhaust on the R, but adding a custom-mapped PC5 does far more for the K than the R. Now that I've experienced both, I'd never ride a K without one again, because it does far more than just add ponies... no more flat spots in curve and throttle response/smoothness is incredible. Oh... tires last far longer on a naked R! I prefer the placement of the mirrors on the K, but the R's are bit more adjustable. I was averaging 46-47mpg on the K until I added the PC5, then it jumped to 50-51mpg (there are lots of open roads around here and very little city traffic). If riding an interstate at steady indicated 70-75mph, the mileage exceeds 51mpg. Even when riding this bike hard, it never goes below 40mpg. I've used full synthetics since 6K service (also used in R). There are more luggage options available for the R than a K13S, but I've never been limited on the K on trips since riding solo. I really like the K, but was never unhappy with the R either. Personalized both bikes with quite a few performance and styling mods.
PM if you have any more questions. I'll PM you some pics of both. Check sig below to see the current mods on the K.
Last edited by Sheep; Nov 24th, 2010 at 10:02 pm.