Kawasaki knew it had something special with its mid-sized parallel twin motor – this engine has been used to power a handful of different bikes from different classes and has even been utilized as an increasingly popular flat-track weapon. The 650cc eight-valve four-stroke DOHC twin boasts digital fuel-injection with dual 38mm Keihin throttle-bodies, producing fun yet practical power for the street with decent low-end grunt and strong mid-range oomph. The (stock 2010) ER-6N (known as the Ninja 650R in the US) redlines at 11,000rpm, though the Kawa twin starts to really flex its muscle in the middle of the powerband. A six-speed gearbox enables the bike to have a better top-speed and while the ZX-6R is likely what comes to mind when most riders think “mid-size Kawasaki race/track bike”, the ER-6N is capable of being transformed into a highly competent racer.
This ER6 has been thoroughly tricked out and is about what you’d expect for a machine competing in the Isle of Man’s Lightweight TT (also referred to as the “SuperTwin Class”. In 2012, the class was re-introduced, allowing four-stroke twin-cylinder 650’s to officially compete on the famous Island circuit. This example uses a highly upgraded and specially tuned 2010 ER-6 parallel twin engine wrapped in a lightened and modified 2006 ER-6 chassis. The SuperTwin now makes more than 25% more power than the stock engine, currently putting down 90+ hp. The bespoke chassis uses a custom subframe and a swing-arm unit from a Versys (with Nitron race shock currently set-up for a 180lb pilot). The forks, yokes, radial calipers and brake-disks, and master-cylinder are all from a 2006 ZX-6R.
Increasing the Kawa Twin’s power – from around 70hp to over 90hp! – required an immense amount of work and quite a few mods. The Mean Green machine’s digital fuel-injection has been helped out via throttle-bodies from a ZX-12R and the Twin now exhales burnt fumes via a full (shorty-style) Arrow race exhaust with balance pipe & lambda bosses on each header allowing for individually mapping each cylinder on the dyno. The 2010 powerplant has received an ample amount of work from renowned cylinder shop Slick Rick Racing Heads, owned by “Slick” Rick McConathy (not the old-school rapper) and home of the SR20 cylinder head.
The 650’s cylinder head was skimmed, ported and “short ported”, (and skimmed barrels too), all to “Slick-spec”. Slick Rick also lightened the flywheel/rotor, modified the clutch to accept an extra friction plate, and utilized stronger cush springs. The Kawa Twin also saw its camshafts undergo a regrind as well as being fitted with Carillo conrods. This example has also been fitted with custom adjustable rear-sets, Harris clip-ons, Koso rev-counter, fuel-pressure gauge, custom aluminum dash and mount, lightweight lithium-ion battery (in a custom aluminum battery box), larger custom radiator with mesh-guard and one-off brackets, quick-action throttle, modified wiring harness (with keyless ignition, will start while in gear), custom relay box, waterproof connectors throughout, Power Commander 3 (with dual maps), and Power Commander ignition-module. Other aftermarket parts found on this example include GB racing engine covers, Hifibre (KMR style) fairing (with large “TT screen”), Hifibre ram air scoop and seat unit, USB rechargeable rain light, modified fuel tank, and a one-off air-box with K&N panel air-filter with said air-box reportedly increasing the mid-range power and bumping peak power up by an extra three ponies.
The Isle of Man TT is one of the world’s most rigorous tests for man (or woman) and machine, pitting racers against 37.73-miles of one of (if not) the least forgiving circuits of all-time. Racing in this iconic competition requires an enormous effort in a myriad of ways. To even participate in the TT riders are required to already have a handful of other road-racing events under their belts, and the majority of competitors aren’t residents of the small Island in the Irish sea, meaning this endeavor requires an enormous financial investment. Though that’s not to say the vast majority of participants will come anywhere close to ever breaking-even. Racing even locally isn’t cheap, traveling overseas with everything required to compete just makes everything markedly more costly.
Riders make absolutely every possible effort to squeeze the maximum performance from their respective machines in an attempt to gain even the smallest edge over the competition, and to fair better against the often deadly Mountain Course. Ex TT machines are world-class production racers that have not only been fitted with top-of-the-line components, but have also had the benefit of competitions leading up to the TT which enables riders and their teams to get their bikes as dialed in as possible. Having a motorcycle set-up correctly makes all the difference in the world.
This ER-Sixer example also comes with dozens of spare parts, including a micron race-exhaust with Akropovic can, various brake components, lighter weight springs, extra rims, sprockets and sprocket carrier, modified std airbox, wiring harness (also modified), stock radiator, engine casings, and gearbox just to name a few. Plus for an additional price the seller has a spare 2012 ER6 engine that has also undergone the complete Slick treatment. The entire list of spares is way too long to write out in its entirety but it includes everything from major components, all the way down to small things like an array of different sized windscreens.
There’s also another meritorious ex-TT 2004 ZX-10R Superbike from the Wilson and Collins Team. The 1000cc Ninja – which was piloted by Paul Dedman and Gary Carswell in 2006 – has a host of upgrades such as full Ohlins suspenders, Harris swing-arm, yokes and rear-sets, AP disks and calipers, Akrapovic exhaust system, custom kevlar airbox with billet bellmouths, kit throttle, Hot Bodies race-bodywork, Brembo master-cylinder, Marchesini five-spoke rims, Aluminum tank, and Mehew motor. This Ex TT ZX-10R example is cosmetically exactly as it was when it was last raced over a decade ago, though it has recently received new fluids, filters, lithium-ion battery, chain, and brake pads. This bike clocked a cool 120.88mph lap of the Mountain Course when it competed in 2006. The stock Zed-ex Tens from this era were already referred to as “widow-makers” so I can only imagine what piloting this thing must be like.
Interestingly Des Collins (the Collins part of Wilson and Collins) had set up a promising young lorry-mechanic from Lincolnshire with a bike to practice with in September of 2003 with the intentions of possibly signing the mutton-chop-sporting racer for his debut TT in 2004. Apparently the two didn’t get along particularly well – a situation only exacerbated by the young racer totaling the bike Collins had paid for – and Des cut the kid loose, though he would find another seat. If you haven’t guessed by now, said kid was a then-22-year-old Guy Martin. Fortunately Collins’ experience with Guy didn’t turn him off from financially backing other racers and the wealthy co-founder of Wilson and Colins Steel Construction went on to provide support for more than 50 racers at just about every level of racing.
Guy Martin, racing in 2004 NOT racing for Des Collins.
This really is the SuperTwin to own. Though the Yamaha MT-07, WK 650i, and Suzuki SV650 are all solid machines, the ER6 holds far more records than the rest of the bikes in its class. The current seller is changing the class they currently compete in and as a resut have put this example up for sale. In addition to cold, hard cash, they are also open to (partial) trading for Yamaha TZ250 (in particular 4DP) parts, and also “may consider a deal for a classic 350cc or 500cc racer”. You can find this Ex TT 2006-framed 2010-powered FrankER6nbike SuperTwin racer for sale here on Racebikemart.com in on the Isle of Man with a price of $10,225. The ZX-10R is also on Racebikemart in the UK but doesn’t have a listed price.