Bike Dissected: 2011 KTM 65SX

Meet SS Racing MXRAD’s fire-breathing KTM 65SX. It produces nearly 20hp, and we’re buggered if we know how young-gun Johnny Bova used to hang on to the thing. This article originally appeared in Transmoto Dirt Bike Magazine‘s 2011 November (#14) issue.

There’s more than meets the eye in the mini-moto world these days. The super-competitive environment has fuelled an entire industry of trick race parts and factory support. But it’s only when you stumble across talented young riders, such as SS Racing MXRAD’s Johnny Bova, that the investment makes sense at such a grassroots level.

Four years ago, Serge Sola – the man behind the SS Racing team – put a plan in motion to foster young racing talent. During the team’s first season, he was quick to enlist the technical expertise of performance specialists, MXRAD, to make the initial two-rider team more competitive. Today, the SS Racing MXRAD team is sponsored by Link International, KTM, RR Racing and Monza Imports, and supports 10 budding young racers in the mini-moto scene throughout NSW. And there’s a growing stack of Australian national and state titles filling the team’s trophy cabinet.

Bova’s factory-esque KTM 65SX race machine has enough performance technology to make a grown man green with envy. In standard trim, the 2011 KTM 65SX produces a touch over 15hp. Bova’s 65SX produces nearly 20hp! SS Racing’s head mechanic, Mark Tanti, also manages MXRAD’s workshop, and he’s the tuning mastermind behind this lethally fast little rocketship.

The Look

For factory appeal, a black Polisport front fender and radiator shrouds, and a white rear fender replace the standard orange/white get-up. Pro-Carbon carbon fibre frame guards protect the chassis, while Custom SS Racing MXRAD graphics from Mongrel Motos complete the look.

Fuelling

The 65SX’s standard Mikuni VM 24 carby has been taper-bored with a stuffed and modified inlet tract to accelerate intake air speed, while the VForce 3 reed-block has been machined in closer to the cylinder. The bike is jetted to run BP Ultimate at a premix ratio of 60:1.

Cockpit

Replacing KTM’s standard Renthal bars are a set of gold anodised Pro Taper mini-high hangers. KTM grips are mounted at each end and the bars are bolted to billet alloy RR Racing triple clamps for increased rigidity in the front-end. Located next to the throttle is the CDI’s map switch.

Suspension

BUD Racing fork insert kits provide both fork legs with rebound and compression adjusters (OEM forks have separated rebound and compression duties). On the rear, a BUD Racing shock replaces the standard WP unit for increased adjustability.

Brakes

Standard front braking power is accompanied by an RR Racing oversized rear brake disc and mounting bracket for additional stopping power. An anodised billet RR Racing adapter mounts the standard caliper to the RR Racing swingarm.

Exhaust

A full European HGS exhaust system lets the screaming 65SX breath more efficiently and produce better peak horsepower. The HGS’s expansion chamber has actually been chrome-dipped for outright factory appeal and added strength.

Big-End

While the 65SX’s cases were matched for a perfect fit, they were also stuffed to reduce the overall internal volume. Stuffing the cases has a supercharged effect on engine acceleration, where the increased crank pressure pushes the piston up faster.

Wheels

Black Excel rims, laced to anodised orange hubs and spoke nipples, replace the standard wheels. While sprockets and chain are race-spec JT and RK. Wrapping the trick black and orange wheel set is a combination of Pirelli Scorpion MX32 Mid-Soft tyres.

Chassis

To prevent the bike from wheelstanding, a cool, 35mm longer RR Racing aluminum swingarm saves weight and extends the 65SX’s wheelbase. And for additional boot traction, there’s a razor-sharp set of BUD Racing pegs with a replaceable serrated-steel inserts.

Cylinder Head

Bolted to the crankcase is a match-ported cylinder with a billet alloy RR Racing cylinder head. The powerband is tuned via an adjustable power-valve in place of the 65SX’s OEM Pressure-Controlled Exhaust Valve. Ignition duties are courtesy of a JD Racing re-mappable CDI.

Engine Magician

MXRAD’s workshop manager and lead engine technician, Mark Tanti, has dedicated his life to racing dirt bikes – a journey that began at a tender seven years old and lasted right up until he turned 30 years of age. Mark is now banging on the doors of the big four-O with three sons to chase around the mini racing circuit and another three stepchildren all piled into the family van. Two of his boys are top Junior national riders, with the most successful of them, Aaron, having wrapped up two state titles this year. A fitter and turner by trade, Mark owes a lot of his engine tuning experience to his old man, who helped develop and hone Mark’s acute skills for fine-tuning dirt bike engines. With three years under his belt at MXRAD, Mark’s been behind many of the race team’s factory rockets. Johnny Bova’s monster-powered 65SX, annihilating mini-moto berms from SA to tropical Queensland, is the latest of his creations.