Spondon Sportster 1440, a Harley-based engine
While plenty of Americans are more than capable of creating a Harley-based engine with a power curve that will punch through the top of a dyno graph, with the lone exception of Erik Buell they all seem quite happy to stick their monster motors in a long-suffering selection of chrome and metal-flake abominations that handle with all the finesse of a wheelbarrow full of manure.
It's not so with one wily European though, and when Jitze Van Der Vinne came across an American serviceman who wanted to unload a big-bore Harley Sportster engine, he decided that it would make the perfect power plant for the bike he'd been planning in his head for some time.
GSX-R upper on a Harley!
He decided to buy British in the shape of nothing less than a creation in big-bore aluminum tubing from the framemeisters at Spondon Engineering. Custom made exclusively for this particular engine, the Spondon frame hangs the Sportster engine from its exquisite aluminum trellis by way of the same rubber engine mounts as fitted to the pre-2004 steel tube framed Buells; not only to isolate the sledgehammer thumps of the big 1440cc motor, but also to allow the frame itself to be used as the oil tank without fear of the engine vibes cracking the aluminum and dumping liquid engineering all over the place.
Obviously, with an engine pumping out something in the region of 150 horsepower with enough torque to climb the side of a house, it needed some proper support. A rear shock from hlins and a set of Showa front forks lifted from a Honda SP1 did the trick.
A simple yet effective exhaust.
A pair of PVM wheels were chosen to get the project off the ground, and a set of 4-piston Nissin brake calipers grace the front wheel juxtaposed with dual wave pattern discs from the Braking company (with another smaller Braking Wave disc at the rear with a twin-pot Brembo caliper for company).
The splendid gas tank came from Spondon with the frame, as did the rearsets. From that point Jitze was on his own to source parts and fabricate the pieces necessary to bring it all together, and in the end he clearly did a top job of giving this HD motor a home to be happy.
Harley Sportster rear end
THE BUYER'S BOX
Spondon Sportster 1440
Front end:Honda Showa forks,billet yokes, PVM wheel, Braking Wave discs, Pro-Taper handlebars
Rear end: Spondon Engineering
big-tube aluminum swingarm, hlins shock, PVM wheel, Braking Wave disc, Brembo caliper, Brembo master cylinder
Motor:H-D Sportster Evo 1440cc4-speed (tuned by Zipper's), Carrillo rods, JIMS flywheels, big-bore cylinders, Red Shift cams, Power-Glide lifters,Pro-Taper pushrods & telescoping pushrod covers, S&S Super E carburetor with performance air filter & manifold, Dyna single-fire ignition system for dual-plug heads, custom exhaust system
Paint: Hugo Brabant
Polish/chrome: Jitze Van Der Vinne
Bodywork:Spondon aluminum fuel tank, fiberglass seat unit, GSX-R headlight, modified Honda SP1 mudguard
Accessories:H-D tachometer, Maligutti headlight, MVF4 taillight.
Builder:www.speedhouse.nl
Owner: Jitze Van Der Vinne