Yoshimura Suzuki GSX-R1000
MSRP: ~ $20,000
Curb Weight: 448 lbs.
Horsepower: 181.7 @ 12,500 rpm
Torque: 81.3 lb-ft @ 10,200 rpm
Quarter Mile: 9.71 seconds @ 147.6 mph
Racetrack Top Speed: 166.61 mph
Best Lap Time: 1:27.21
Yoshimura Suzuki GSX-R1000
Our outing at Willow Springs marked the debut of the MotoUSA Project Yoshimura Suzuki GSX-R1000. For Part 1 of our multi-stage story, this proved the perfect place to not only shake down the newly-built machine, but see how it stacked up to the others at the same time. As it also happens, with the cost of parts and labor added, the Yosh Suzuki comes in at nearly the same price as the Aprilia. This gave us a perfect comparison of two very different motorcycles which lighten the wallet equally.
For the first stage of the build we kept things street-legal, aiming to make the ultimate road-going Superbike. It’s widely known that if you have a Suzuki and want more power there’s one company to turn to – Yoshimura. It’s hard to dispute a company with the last 10 of 11 AMA Superbike championships to its name, all on Suzuki GSX-Rs. And with the addition of the YRS (Yoshimura Race Shop) program which began late last year, our project GSX-R provided a perfect opportunity for us to see what exactly the Japanese company has available for the performance-seeking consumer.
We started by installing one of Yosh’s engine-swap-program motors. This gave us a full Superbike-spec powerplant quickly and easily. That was mated to Yosh’s EM-Pro software system to control fuel delivery and their R-77 exhaust, while a BMC airfilter aided in intake flow. Finally, case guards were added to protect our investment.
The Stage 1 Yoshimura Suzuki GSX-R1000 (top) may look close to stock but under that bodywork lurks a monster; Yosh’s power-making and beautifully crafted R-77 exhaust (middle); Showa’s Factory Kit shock (bottom) was added along with a Yosh link to help handle the engine’s additional 30 hp.
To give you an idea of how much value for the money the YRS engine-swap really is, the rental motor is only three to four horsepower down on Tommy Hayden’s factory American Superbike-spec machine. And getting one is as simple as bolting it in your bike, thumbing the starter and racing – then give it back after the weekend. Yoshimura will also replace it with a new unit or perform whatever repairs are needed if anything mechanically goes wrong (as long as it’s not from gross negligence).
And this can be yours for $1500 per weekend of racing. Considering it would cost nearly that to simply maintain a modified race engine for one weekend, let alone use a full-factory unit, that’s what we call a smokin’ good deal. As for those who want to build their own SBK powerplant for the street or track days, Yoshimura will make you the same extremely-potent motor for roughly $7500.
So just how fast is the engine? Well, to just simply say fast would be the understatement of the century. Despite the fact that we didn’t get proper gearing in time for our test and had to use the ridiculously-high stock setup, the GSX-R would still wheelie under power exiting Turn 9 at 120 mph! Frankly, even with the stock gearing it’s an absolutle brain-melting missile.
But its true beauty lies in how easy the power is to use and control. Combined with Yosh’s tuning of its EM-Pro ECU, from 2000 rpm all the way up to redline the bike ran like a dream – it just happens to be one of those crazy skydiving-without-a-parachute dreams. But while seamless power delivery did it’s best to mask the beast within, there’s nothing that can truly tame the rush those 999ccs are capable of producing, especially at over 130 mph. And we can’t get enough of it.
It’s no wonder, as a look at the dyno charts shows an amazing 181.7 hp and 81.3 lb-ft of torque at the rear tire. This is backed up with the on-track data. The Yoshimura-built Superbike engine propelled the GSX-R to a blistering top speed of 166.61 mph, nearly 5 mph up on the Ducati and over 12 mph faster than the Aprilia. It’s also extremely strong all the way through the faster sections of the track, entering Turn 8 at 146.1 mph, clipping through the apex at 127.2 mph and exiting with a blistering 133.8 mph. One can only imagine what it will do with proper gearing.
But power is also nothing without control, so we focused on basic and affordable chassis modifications to take Suzuki’s already potent GSX-R to the next level of racetrack and canyon-road devouring prowess. In the suspension department we added a Showa Factory Kit shock and Yoshimura linkage along with a massaged stock Showa fork and fork-extender caps. The aim was to match chassis performance to its monster motor’s abilities. Not an easy task, though with the help of some of the race team’s suspension gurus, we were able to make substantial strides without investing too much coin.
High-speed mid-corner stability from the Yoshimura-built Suzuki GSX-R1000 Project Bike was rock solid.
As a result the bike handled far better than the base machine, especially in terms of the rear shock. Where the progressive spring and link used on the OE unit makes it nearly impossible to tune out corner-exit pumping under acceleration, we had no such issues with the Showa unit and Yosh link, despite the fact we were putting over 30 additional horsepower through it. This is the result of better valving, slicker action and the use of a consistent-rate spring and flatter-rate link. This kind of power through the stock shock would have been downright scary, thus if you are going to go big with the engine we highly recommend you invest in suspension that can handle it.
Up front the fork was plush over the small stuff but handled hard braking well and was very balanced with the rear shock. The combination of the two equated to one of, if not the most stable big-bore bike I’ve ever ridden through Big Willow’s Turn 8 and 9 section. While most bikes are sensitive to gusts of wind at 140 mph at knee-dragging lean angles, the Yosh Suzuki wouldn’t budge no matter what came its way.
“I’m absolutely flabbergasted at how on-rails the Suzuki was through (Turns) 8 and 9,” Waheed says of the Yosh GSX-R. “I could go in there on any line I wanted, at any speed I wanted, and no matter what I did it just shot around those two corners probably faster than I’ve ever been. If only every bike was so easy to get through that scary section of the track then, well, it wouldn’t be so scary anymore.”
Yosh Suzuki GSX-R1000 VBox Data @ Willow Springs
– A blistering 166.61 mph down the front straight and a whopping 146.1 mph down the back shoot showed what the Yosh engine was capable of. The comparison-leading Turn 8 and Turn 9 speeds display the chassis’ high-speed abilities.
We opted to leave the fork and shock set at the stock height and as such the bike didn’t flick from side to side nearly as quickly as we would have liked. Not that is was sluggish; we just would have liked more urgency when changing direction. As such, this is something we are in the process of changing for Part 2, so be sure to stay tuned as the racing phase of the project begins later this month.
This was visible in the data too, as while the Suzuki was stable and very fast through the Turn 8-9 combo, in the slower Turns 2 and 4 it was at the back of the group. Speed at the apex of Turn 2 was a meager 86.6 mph, almost four down on the others, while in Turn 4 it was also last, though only slightly down on the Aprilia – 54.3 mph verses 54.5 mph – Mirroring our rider impressions. Though with some ride-height adjustment this could easily have been remedied.
Another area where we would have liked more performance was the brakes. We added Galfer pads and steel-braided lines, yet combined with the stock master cylinder and calipers it still produced lackluster results. We’ve never been a big fan of the Suzuki liter-class machine’s binders, especially the feel though the OE master. And although the Galfer parts helped and would be an adequate street set-up, for track work a little more performance is needed.
With Stage 1 in the books, Stage 2 begins. By the time you read this the GSX-R1000 Project will be fully disassembled and in the process of being turned into a full-blown racebike.
Other than some slight gearing, geometry and brake issues, we came away quite surprised with the Yoshimura Suzuki GSX-R1000. For virtually what you would spend on a mid-level exotic European sportbike, it’s easy to have Yosh turn your Japanese machine into a motorcycle which circulates the track substantially faster while being a downright missile in a straight line. The GSX-R1000 is a potent street bike in stock form, but with this bike the boys from Yosh turned what is already a 9 out of 10 to a 12 – or maybe higher.
If you want to haul the mail around the track and smoke anything on the road at the slightest twist of the right grip, simply pick up the phone and call Yoshimura. It’s no wonder these guys have been so successful at racing. And now it can ALL be yours from YRS at more-than-reasonable prices!