Kawasaki Let Us Hang Onto Our '07 ZX-10R For A While. Of Course It Didn't Remain Stock For Long
Project Bike
In The Normal Course Of Magazine Testing, Bikes Are put through the wringer and then returned to the manufacturer-job done, thanks for playing. Sometimes, however, we get the urge to hang on to a bike and tinker, maybe to improve some aspect of the bike we didn't like, or perhaps to test some aftermarket products. And sometimes we just want to keep a bike around because we like it so much. Case in point: this '07 Kawasaki ZX-10R. After our last year's literbike comparison test ("Literbike Lunacy," Aug. '07) we found that swapping out the Kawasaki's stock front tire made a huge difference in the bike's behavior, transforming it from a ponderous handful on the street to a neutral-steering rocketship. With that change, we didn't want to return the ZX-10R-partly because it was so much fun to ride, but mostly because the tinkering gene had kicked in. If a front tire made that much difference, what would, say, some aftermarket wheels do?
This multifunctional radial-mount Brembo RCS master cylinder is a work of art. CNC-machined from an aluminum forging and anodized, the RCS has an adjustable pivot point with 18mm and 20mm settings, allowing it to be used for street or track as well as a variety of different calipers. The folding lever has a span adjuster that doesn't affect the leverage and can be set up with a remote adjuster for racing, and there is even a brake-light switch incorporated.
It was a golden opportunity to try Marchesini's forged aluminum wheels, and because the company has moved under the Brembo umbrella we thought we'd sample Brembo's new line of High Performance goodies at the same time. As usual the snowball effect resulted in a couple of weeks' worth of UPS deliveries and a 165-horsepower toy that reminds us of why we liked the original, '04 ZX-10R so much: Our modified Kawi is a light, fun package that is docile and playful as a kitten when puttering around but ready to pounce like a lion anytime you're willing to pull its tail.
The real impetus behind our project Kawasaki is the wheel and brake combination. Brembo's HP line includes calipers and rotors intended for the street/track rider, with performance and pricing a step down from the full-on Superbike bits. The two-piece radial-mount calipers run $1550 for the pair-still not cheap, but less than half the cost of the higher-spec, one-piece units-and the rotors cost $610 for the pair. We matched the discs and calipers with one of Brembo's RCS (Ratio Click System) master cylinders, which also falls under the HP line and costs $365. Marchesini's forged aluminum wheels-not quite as light as their magnesium counterparts but significantly sturdier and cheaper, and lighter than the stock wheels-run $2222 for the set.
Brembo's new High Performance line is highlighted here with the replacement rotors and calipers. The radial-mount calipers may look like the one-piece race units but are two-piece and bolted from the rear. Marchesini, now part of Brembo, likewise offers forged-aluminum wheels that are more suitable than magnesium for the street/track-day rider. Galfer provided us with the brake lines and fittings to match. The assembly shown here - Marchesini forged-aluminum wheel, Brembo discs and Continental tire - weighs in at just less than 23 pounds, a savings of four pounds compared with stock.
There's no point in mounting up shiny new wheels with old tires, so we spooned on a set of Continental's new ContiRace Attack high-performance sport tires. The new tire is a development of the company's ContiSport Attack, using a continuous compound technology and sparser tread pattern for more grip. The Race Attack is a street/track tire that is also available in a competition version, but we chose the standard version in keeping with the ZX-10R's intentions. One feature that prompted us to pick the Continentals is that the rear tire is offered in both 190/50 and 190/55 rear sizes, the 55-series tire matching the Kawi's stock tire. Street prices for the new Contis typically run $340 per set.
Out back the Marchesini wheel called for a nonstock sprocket to fit; we sourced an aluminum sprocket ($74.95) from Driven USA, which offers sprockets and chains in practically any custom combination with a variety of colors to choose from. While we were at it we ordered a one-tooth-smaller front sprocket ($29.95); both were in stock 525 pitch so we wouldn't have to mess with the chain. Installation of the wheels and brakes included a couple of snags: The rear disc bolts needed some washers underneath to account for shallower counterboring of the wheel, and the calipers and master cylinder needed different banjo bolts from stock, which weren't included in the kit. Galfer came to the rescue here with color-matched stainless steel lines and the correct fittings for everything ($98).