Not that the ZX-10R needed more power, but we couldn't stop ourselves from ordering a KR Tuned full exhaust. The beautiful stainless steel header and carbon canisters are flawlessly constructed, and performance is top-notch. Jeremy Toye of Lee's Cycle (858/541-2080, http://www.leescycle.com) installed the pipe and created a custom Power Commander map to match. Toye pointed out that simply installing the Power Commander with a map downloaded from the internet actually reduced power and that the full benefit of the pipe was only realized with a custom map-as is the case with most installations.
Knowing how our last-year's GSX-R1000 project came alive with the addition of a timing retard eliminator that tricks the bike into thinking it's in a higher gear-and using the more aggressive mapping to match-we found a similar unit for the ZX-10R. While we were on the phone with Cal-Sportbike ordering the Heal Tech GI Pro we also arranged for a Pipercross foam air filter ($58.99). That's the limit of our ZX-10R engine modifications; why mess with excess?
This adjustable clutch lever from Pazzo Racing is machined from solid aluminum and has an easily reached adjuster. The levers ($184.99/set from CTSmoto) are available in short and long (shown here) configurations for a number of models - including our Brembo master cylinder - and a variety of anodized colors. | 
Heal Tech's Gear Indicator Pro with Advanced Timiing Retard Eliminator (whew!) shows gear position with this huge, bright LED. The device ($159.99 from Cal-Sportbike) also has a pushbutton to select one of three settings: In standard mode the gear-position signal is uninterrupted to the ECU; the other settings default the ECU to fifth and sixth gear for more aggressive timing and fuel maps. In any setting the correct gear is always displayed. | 
A smoked widescreen from Hotbodies adds some bling to our project bike. The $69.95 Grand Prix version is one inch taller than stock with a dual radius, adds some much-needed wind protection on the freeway and doesn't block the top of the tach like the stock part does. |
The danger with most project bikes is that they often turn into a "hop-down," as we sometimes call them, and the combination of the selected parts ends up worse than stock. Nothing could be further from the truth here: Our project bike exceeds our expectations, working better in almost every aspect. Steering is light and delightfully neutral, a nice change compared with the stocker. The lighter front end helps transitions, and the ZX feels much more nimble than the few pounds saved in the front end would suggest. Certainly magnesium wheels would be a step better again, but with aluminum comes the security of knowing the wheels will survive the Department of Public Works' best attempts to bend them on the edge of a pothole.
Likewise the Brembos are a huge improvement over the already-good stock parts. Braking is one-finger powerful, although some heat is needed in the system, and response is crisp without being grabby or too progressive. The Continentals provide excellent grip and the same neutral steering as the standard (non-OEM) front Dunlop Qualifier, and wear looked better than average for a high-performance sport tire.
The ZX-10R is known for being smooth and ultrapowerful, and our modified bike has even more steam and delivers that power even smoother. The custom map gives instant throttle response at any rpm, and in concert with the smaller front sprocket and lighter front wheel it makes for a very, shall we say, happy front end. Toggling the map on the GI Pro reveals an interesting detail: While the off/on throttle is smooth on the default setting, switching to one of the other maps-fooling the ECU into thinking the bike is in fifth or sixth gear-adds a bit more power at lower rpm at the expense of the buttery throttle response. Further mapping of the Power Commander may clean that up, but in the meantime the GI Pro stays on its standard setting.
There is one flaw in our project Kawasaki: The extra power and stronger brakes exacerbate the stock bike's chassis pitch, and the bike wheelies too easily under power-even when leaned over in a corner. Fun, yes, but some suspension mods would be next on the list to better control the chassis. Still, it's the overall package that brings a grin to our faces every time we ride our potent ZX. The mix of silky throttle response, acres of usable power, neutral steering and crisp, responsive brakes gives the rider more confidence than the stock bike ever could. It's a fantastic daily rider as well, running clean and smooth in town and on the freeway. Wait, there is another flaw: Now we have to give the bike back to Kawasaki.
The dyno shows more power almost across the rev range for the modified ZX-10R, along with more overrev, but doesn't show how smoothly that power is now delivered. | 
The KR Tuned frame sliders have a bracket that mounts to both front and rear engine mounts, with the slider itself mounted to the bracket. The unique design means the fairing doesn't have to be cut, yet the slider is far enough forward to not interfere with your legs. The setup does add a couple of extra pounds, however. | 
The Kawasaki's rear end cleaned up nicely with the KR Tuned canisters and Marchesini wheel. The KR Tuned exhaust weighed in at just 15.8 pounds and is reasonable for most of our ZX-10R's performance gains. The aluminum sprocket from Driven USA is necesary to mate with the Marchesini wheel. |