Kawasaki 2003 ZX6R 636cc and ZX6RR 599cc models
Performance Setup Parts & Tips
Kawasaki offered in 2003 two versions of the highly competitive new ZX6. The "base model" ZX6R features a 636cc engine with a 68x43.8 mm brore and stroke, with a 12.8:1 compression. But because this bike has too large of a displacement to race in the normal 600cc Supersport and Superstock classes, they also offer at higher cost a limited edition ZX6RR to race in those classes with a 599cc engine with 67x42.5 bore and stoke and slightly higher 13:1 compression.

The limited addition ZX6RR costs about $1,200 more than 636cc model, and in stock form it is slightly down on power to its bigger ZX6R brother. If you aren't roadracing in the 600cc Superstock class, you are better off with the lower cost and better performing ZX6R. For SBK World Supersport 600cc racing where engine modifications are allowed there is a ZX6RR Factory Race Kit from Kawasaki distributors (similar to what Yamaha offers for their YZ6) which includes different thickness head gaskets to alter compression, race valve springs and camshaft kit, different gearbox ratios, an adjustablr racing ECU with PC computer hookup, tacing oil pump and generator, Akrapovic exhaust, and a larger water radiator as needed.

As you may or may not know, all 600 and 750cc SuperSport bikes in AMA have to be box stock except they can run an aftermarket exhaust, recalibrate the carburetion / fuel injection, and improve the suspension with a better shock and maybe some internal fork mods, plus a change in sprockets, chain and tires. The SBK Race Kit for the ZX6RR can't be use here in America for AMA SuperSport racing.

Team Kawasaki USA for 2003 races the ZX6RR in AMA 600cc Supersport with riders Tommy Hayden and Tony Meiring where they are having a difficult time against the Yamaha YZ6 and Honda CBR600RR. While strangely enough, Tommy is also racing the more common ZX6R 636cc model in the 750cc Supersport class against the class dominate Suzuki GSXR750s and Tommy is handily winning the class. Which proves either, the new 600 class bikes are now quicker than the current 750s, or the slighlty bigger 636cc ZX6R is a real giant killer against the 750s.

Team Kawasaki's Tommy Hayden in action on the ZX6R or is it the ZX6RR?

Our suggested way to go in setting up any Japanese 600cc SuperSport bike including the Kawasaki ZX6RR models is run the best performance exhaust system on the market which is an Akrapovic, run a jetting kit or fuel injection recalibration device from DynoJet or Factory Tuning at their recommended settings. For suspension a race quality rear shock from Ohlins, Fox Factory or Penske are the way to go. The new 41mm forks are fully adjustable and have top-out spings to aid adjustability, and probably won't need reworking. But if you feel they do, Lindeman Engineering is the best place to send them. Kawasaki USA has enough of a budget they can install Ohlins dampening internals in their team's front forks. Our Paddock Garage Suspension Tuning section will provide you with all the information needed to set up the suspension and handling of your bike.

If you still want more performance for your ZX6R bike, the next step is cams and higher compression pistons. But you'll need to run race gas with the higher compression pistons, and with the cam change the bike won't be much fun on the street. J&E Pistons is the top source for sportbike pistons in America, and Muzzy's would be a good contact for racing camshafts.

You can also attempt to buy parts form the Kawasaki ZX6RR Race Kit, but you'ld probably have an easier time buying them from a Kawasaki distributor in Europe or Japan. The British sportbike magazines like SuperBike and Performance Bikes are another good source for current hop-up articles and companies selling these racing parts. A top performance shop in Great Britain for Kawasaki performance parts and tuning is MSS Performance at phone 011 (44) 208-763-5700. Akrapovic is the recommended race exhaust system for Kawasaki sportbikes.Akrapovic race systems extensively dyno tested prior to production to achieve the best possible power.They feature expensive to build, but worthwhile performance gains from tapered header pipes, crossover balance tubes on the down pibes, and 4 into 2 into 1 collector tubes for a broader powerband.

Eric Bostrom's factory ZX6R and ZX6RR bikes are basicly stock with the exception of an Ohlins rear shock, Akrapovic full race exhaust system, and probably the fuel injection remaping offered by the Factory Race Kit CPU with PC hookup. A DynoJet Power Commander should do just as well if you have a dyno to set up with, otherwise just use DynoJets recommended programing.