Suzuki GSX-R 1000 | Yoshimura Project Build
Ultimate MotorCycling Suzuki GSX-R1000 Project Build
Much progress has been made in the last few years in motorcycle technology, particularly in the area of electronics. Fuel injection is now sophisticated enough that different fuel maps can tailor an engine’s output to a rider’s preference. Beyond that, traction and wheelie controls are now appearing on streetbikes, while anti-lock braking is commonplace.
Although these technical gizmos are welcome safety devices – especially on the street where unpredictability is the only certainty – most sportbikes out there still aren’t equipped with the above devices.
Lacking electronic interference is actually not a terrible thing; at the end of the day riding safely has to be the responsibility of the rider, and no amount of smart electronics can replace smart riding. Indeed, traction control has to come from your right wrist.
Having said that, when we had the opportunity to revamp a staffer’s 2007 Suzuki GSX-R1000 project bike, it was a chance to see if the latest technology could both improve safety, as well as enhance the rideability of the Gixxer.
Although Yoshimura R&D develops parts for many different brands and genres of machine, it is best known for its fire-breathing Suzuki roadracers, and in 2012 Yoshimura campaigned in AMA Superbike a pair of great-looking custom-painted Suzuki GSX-R1000s.
Our project bike lacked a stock fairing, so we had the idea of replacing it and replicating the Yoshimura race paint. As any crasher will tell you, replacing bodywork can be a costly undertaking. However, by sourcing an entire fairing kit from an overseas web-based company – Extreme Fairings – cost was kept to around a third of the OEM price.
For approximately $600, Extreme Fairings supplies a complete body kit that includes the front fender, gas tank/airbox section, as well as seat cowl, heat shielding, and a clear or tinted windscreen.
There was nothing wrong with the supplied screen, but we opted to fit a Zero Gravity Double Bubble windscreen instead. The wedge shaped design is claimed to help with aerodynamics at speed, though in this application I admit we went for it purely for the looks.
Sourcing foreign products can be tricky, and not all Chinese-manufactured bodywork is of similar quality. Extreme Fairings’ pieces are top-notch injection molded ABS plastic, and the attachment lugs are an integral part of the relevant piece, rather than simply glued-on tabs.
Astonishingly, the Extreme Fairings price also includes custom painting at no extra charge. You can get a full set of bodywork, custom painted in any design, with any set of stickers and logos you desire, in metallic or gloss paint. They are able to work with any design except graffiti, and the product arrives with a full warrantee – if you’re not satisfied they will work with you until you are.
We simply sent Extreme Fairings a couple of pictures of the Yoshimura racebike, and three weeks later our bodywork arrived. Fitting it provided the usual aftermarket niggles of making sure the holes and tabs lined up properly, but with very little massaging the bike came together perfectly. The paint isn’t quite flawless, but it is darn good, and we are more than impressed with the result.
New bodywork and paint clearly called for new fasteners, so a Pro Bolt Titanium Fairing Kit in blue was used to piece everything together; these bolts are precision crafted, and make short work of replacement as – unlike the OEM bolts – they are sold as a complete kit instead of individually.
A selection of Yoshimura R&D hard parts in the Magnasonian (copper-colored) finish were also added to the Gixxer. They included case savers, an oil filler plug, timing inspection plugs, axle adjuster blocks, a steering stem nut, a fender eliminator kit, and bar end weights. For weight reduction and improved engine breathing, a full Yoshimura stainless exhaust with carbon fiber muffler replaced the stock Suzuki unit, and the look was completed with a Yoshimura lightweight muffler bracket. The bike is now a drop-dead gorgeous traffic-stopper.
The 2007 GSX-R1000 is plenty powerful out of the box, so we opted to keep the engine stock. Regardless, the addition of a Bazzaz Z Fi TC unit and Quick Shift, Yoshimura exhaust, and K&N air filter required a trip to JETT Tuning, based in Camarillo, Calif., to set everything up properly using a dyno.
John Ethell, who has has been awarded the Crew Member of the Year four times by the AMA, established JETT Tuning in 2005 as a way to bring his considerable racing expertise to the public. Highly respected within HRC and American Honda, Ethell has among other accomplishments been crew chief for Jason Pridmore at Hypercycle, Aaron Gobert, and Jake Zemke at Erion Racing. He was also chassis mechanic for Miguel DuHamel, and engine man for both DuHamel and Nicky Hayden at American Honda.
More recently, Ethell was crew chief for Roger Lee Hayden on American Honda’s Moto2 entry at last year’s Red Bull Indianapolis GP. With that resume, and his legendary attention to detail, it would be child’s play for him to fine-tune our Project Yoshimura Suzuki.
Setting up the fuel mapping on the JETT dyno, Ethell’s stated goal was to optimize the fuel/air ratios. “Peak numbers have never interested me‚” Ethell said matter-of-factly, “if you get the fuel-air ratio right, the peak numbers will take care of themselves.”
For us, it is all about rideability, and Ethell’s statement rang true. Although the Gixxer’s power is outstanding, there is a big dip in the torque curve down low. By optimizing the fuel-air ratio to a goal of around 13.6:1 in the cruising range, and 13.4:1 on the top end, the big Suzuki motor ended up with peak rear-wheel horsepower of 176.5 at 12,000 rpm and maximum torque of 83 ft/lbs at 5400 rpm.
Those kinds of numbers and “user-friendly” aren’t often seen in the same sentence, but Ethell’s tweaks to the fuel mapping have produced an extraordinarily pleasant bike. The Project GSX-R1000 now has linear power and such a good throttle connection that when revs rise and the bike goes from docile to wild, it is intuitively easy to control.
We added two teeth to the rear sprocket to bring down the tall gearing and, coupled with the Bazzaz Quick Shift, the Gixxer will loft the front wheel a couple of feet off the surface and then hold it smoothly and controllably through the first four gears. It is one thing to hold a wheelie at the balance point; it’s quite another to lift the front a little and hold it using power for an extended period. This is impressive stuff from the cockpit for sure.
Ammar Bazzaz first entered the AMA Superbike scene in 1997 and, as Mat Mladin’s race engineer at Yoshimura, he helped Mladin bring home his first three AMA Superbike championships. Starting his own company in 2003, the Chino Hills, Calif. based Bazzaz brings his high tech wizardry to regular sportbikes with a line of unique, affordable, state-of-the-art engine management products.
Installing somewhat easily using the OEM connectors, the Bazzaz Z Fi TC unit comes with default maps for Fuel Control, Traction Control, and Quick Shift. While it is plug-and-play, the Z Fi TC box certainly performs best if it is professionally set up.
The level of complexity can be quite intimidating if you don’t know what you’re doing. However, having watched John Ethell set up both the Traction Control map and Quick Shift timing, we have subsequently found it easy to connect my laptop with the supplied USB cable, and fire up the free software (downloadable from the Bazzaz website) to adjust the traction thresholds. There is also an offline mode that we found useful to practice with. The Z Fi TC unit doesn’t interfere with Suzuki’s own fuel maps, so the stock A, B and C (Rain) modes still work as originally intended.
A handlebar mounted flip-switch gives a choice between two separate maps that cover Fuel Control, Traction Control and Quick Shift, and the rotary dial detents to the center and allows a plus or minus adjustment to the Traction Control sensitivity on the fly.
Traction control is a cool addition to any motorcycle and, unlike many of the OEM systems that need wheel speed sensors to determine loss of traction, the Bazzaz TC is a rate-of-change system that uses rpm spike data to determine wheel slip.
Fully tunable by throttle position, engine speed, or gear selection, it cuts the spark to certain cylinders, thereby dialing back the power slightly. Manifested as a slight popping or stuttering sound from the exhaust, the Traction Control is easier to hear than feel when it’s in action.
Bearing in mind this is a system designed primarily for racetrack use, it will not save you if you insanely wrench the throttle mid-corner, but it is nice to know that there’s a system in the background that will help manage the enormous power, especially in changeable road traction conditions. This isn’t a system to be exploited as a racer would; rather, it is an addition to one’s safety arsenal.
The Quick Shift device cut-times can also be adjusted and, although the default settings are quite good, Ethell did marginally speed up the cut-time from first into second gear based on his experience. The Suzuki’s gearbox is butter-smooth and has a short throw at the lever, enough that the Bazzaz Quick Shift works flawlessly and feels like it must come stock with the bike. Traction Control is a safety device that is only used when you step over the edge; but the Quick Shift is an immediately useful tool in constant use, and something I just wouldn’t do without.
Rick Wall, co-owner of Sawing Services in Chatsworth, Calif. did the wrenching on our project, and his creativity and attention to detail are unmatched.
For the perfect streetbike setup, Wall custom-machined a top triple clamp to his own specification that allows an upright handlebar to be fitted. A Buell tapered bar was sourced and, after a little trimming of the top fairing for brake and clutch clearance on full lock, an endlessly comfortable riding position was created. The stock mirrors were retained, though you now have to lift an elbow for a clear view to the rear. The extra comfort of the upright riding position is well worth the trade-off.
Changing the riding position naturally changes the motorcycle‚Äôs weight distribution, and the Project Gixxer initially had a slightly vague-feeling front end and a tendency to run wide on corner exit. Examining the still-pristine front Dunlop Sportmax Q2 confirmed that it was being underworked due to the lack of front-end weight. Raising the rear by 12 mm and dropping the front by 8 mm changed the attitude enough that the difference was visually noticeable. The reduced ground clearance doesn’t seem to be a factor on the street where lean angle is not as extreme as on track.
With so much weight taken off the rear, we were a little unsure whether the problem would migrate to the back of the bike and turn it into a slithering, highside monster that would test the Bazzaz electronics to the max. We need not have worried.
Although it is probably not an ideal track set-up, on the street it works incredibly well, and the Suzuki became a perfect-handling machine. Galespeed Type-R aluminum wheels save unsprung weight and, combined with the extra leverage of the upright handlebars, the Project Gixxer turns very quickly. There is no feeling of nervousness, no doubt due in part to the stock electronic steering damper.
It is nice to be able to take a wide line and get the bike cornering efficiently; turn-in is absolutely precise, and the rider can place the bike exactly where he wants; changing lines doesn’t faze the bike in the slightest. It is stable in mid-corner, even in high-speed sweepers, and as the rider comes back on the throttle on corner exit, the Gixxer is solidly planted and doesn’t try to run wide.
Bump absorption at the rear is managed by an Ohlins TTX (Twin Tube) shock that separates the rebound and compression damping functions. Usually the piston moving within a single tube shock creates bubbles in the fluid as it is forced through the valves in the piston. Those bubbles, known as cavitation, naturally create damping inconsistencies as the piston goes back and forth.
Ohlins’ TTX system links two tubes in front and behind a solid piston, and the fluid then simply moves between the tubes replacing itself from in front of the piston to the back of it (and vice versa). The valving that creates damping is then placed in the second tube where it cannot create bubbles in the fluid.
The end result is a shock absorber that reacts so smoothly and quickly that the tire has much better contact with the road, and that means better grip. The difference in performance between the stock Suzuki shock and the Ohlins is dramatic. Even if you are not an expert rider, it is more than worth trading up.
Nickel-plated Brembo radial calipers and master-cylinder handle the stopping duties at the front, and replace the stock Nissins. New GSX-Rs now come with Brembo Monoblocs as standard, and they are another excellent upgrade, especially if you are a track day regular.
The Brembos have plenty of feel, and the master cylinder doesn’t have that instant, grabby over-bite that can be so dangerous on the street; the bite increases linearly as more pressure is applied. The big advantage of the Brembo calipers is they do not distort when they get hot – not really a factor on the street, but at a track it certainly can be.
Turning a contemporary sportbike into a superbike for the road is not a particularly challenging task, but it sure is a rewarding one. We chose to focus on electronic management and upgraded brakes to tame the Suzuki’s prodigious horsepower, and at the same time reduced weight and upgraded the suspension to help it handle well on the street. Our Suzuki GSX-R1000 Yoshimura Project Bike also looks like dynamite, and the upright riding position makes it all-day comfortable. Anyone want to go superbike-touring?
This story is featured in the Mar/Apr 2013 issue of Ultimate MotorCycling magazine—available on newsstands and good bookstores everywhere. The issue is also available free to readers on Apple Newsstand (for iOS devices) and Google Play (Android). To subscribe to the print edition please visit our Subscriber Services page.