With a workshop name like “it roCKS!bikes” the Portugese builders Osvaldo Coutinho and Alexandre Santos have set the bar high for themselves. Luckily the self confessed “addicted” custom builders (and fully qualified engineers) have what it takes to build bikes that warrant an ‘it rocks!’ reaction. Their latest build, the XJR1300 CS_04 Stealth, lives up to expectations; however by definition dictionary.com tells us that stealth means “the act or characteristic of moving with extreme care and quietness” which is something I would argue this beast is incapable of doing.
The build started when a good friend brought his 2003 XJR1300 SP into the it roCKS!bikes workshop. “At first, he just wanted a new tail, seat and to fit some parts like the up-side-down fork, Brembo calipers and the Motogadget motoscope, but we told him that if we put our hands on his bike, in the end he would get a whole new bike…” With the idea of a full build approved the three began sharing ideas and the name stealth was chosen due to the owners love of aeroplanes. The owner also had a good idea of how he wanted the tail end to look so they had a starting point for their Stealth build and the Yamaha was disassembled. From the original bike the gas tank, engine, part of the frame, swingarm, rear shocks, wheels and brakes were all retained but everything else had to go!
Kawasaki ZXR up-side-down forks and Brembo brake calipers were mounted to the front end using custom made CNC adapters and an all new steering stem. In the rear a pair of Ohlin’s shocks were used to complete the suspension upgrades. The wheels were stripped and wrapped in new Dunlop Sportmax rubber and the engine, which was in good working order, received a shot of high temp matte black paint and a new set of stainless bolts and fasteners. To open up the frame the air box was discarded and a custom CNC machined velocity stack was mounted to each of the four carbs and a defensive fender made to protect the carbs from flying debris off the rear wheel. The exhaust is a custom 4-2-1 titanium unit with thermal wraps in the headers and to get the bike running smoothly with the increased flow the carbs were re-jetted and tuned. The only other performance modification made was the adaption of an oil cooler to help keep internal temperatures down.
“We used a digital dashboard made by Motogadget called the “Motoscope Pro”. This unit is packed with features like a rev counter, speedo, 0-100km/h acceleration times and a g-meter and we mounted it using an aluminum bracket we designed and cut out on a CNC.” The license plate bracket and turning signals are from “Rizoma”, and the controls are “Motogadget” m-Switch blocks which conveniently come in black. “Since we had to keep the stock gas tank we fabricated a seat and the metal rear section with a shape that follows the lines of the tank. The seat is a custom, handmade light brown leather piece and all the custom paintwork was done with an airbrush before being spayed with a thin layer of matte varnish.”
While there’s no denying the CS-04 Stealth looks amazing the question that’s always on the tip of everyone’s tongue is, of course, how does it ride? “Since we reduced a massive amount of weight from the XJR by removing parts, using aluminium for the new ones, making an exhaust from titanium and using a tiny lithium battery the bike feels very light and the tuned engine became a serious powerhouse… it pulls hard at any speed!” After appearing at the Lisboa Arts & Moto show in April the Stealth is now being used exactly as it should, as a daily rider tearing up the streets of Portugal.