Aprilia's 450 and 550cc supermoto and enduro V-twins are now available in South Africa - where other manufacturers offer enduro or motard racers with big vibratious single-cylinder engines the, Aprilia lines up with light, hard-revving, V-twin engines.
The RXV Enduro 4.5 (450cc) and 5.5 (550cc) and their SXV Supermoto siblings use compact V-twins to deliver smooth power and torque in nimble, user-friendly packages.
The short-stroke/big-bore engines, designed and built completely in-house at Aprilia's Noale headquarters near Venice, measure 79x49.5mm and 80x55mm respectively and produce a claimed 45 and 52kW - in a package that's actually smaller and lighter than that of most comparable singles.
This is mostly due to the 77-degree angle between the cylinders, says Aprilia.
The factory tested various configurations to get the most performance with the least vibration and claims the new V-twins shake less than any big-single bogtrotter on the market - even without balance shafts.
Wet liners mean quick, easy rebuilds while the dry-sump lubrication, single overhead camshafts and four titanium valves per cylinder are safe up to 13 000rpm.
All the covers are superlight magnesium and there's no kick-start - why bother when modern electric starts are so reliable, says Aprilia. Each of the four models weighs less than 120kg dry.
Carburettors have been discarded in favour of electronic fuel-injection with 38mm throttle bodies on the 450s and 40mm throats on the 550s.
Even the 550 displaces only 275cc per cylinder, allowing the use of very light, compact, one-piece crankshafts.
Aprilia off-road V-twins use lightweight steel trellis frame spars interference fitted to pressed aluminium side plates with the engine forming an integral part of the frame and acting as a fully stressed member.
They also have 45mm Marzocchi upside-downies - specially calibrated for enduro or supermotard use, depending upon the model - variable-section aluminium swing-arms and Sachs multi-adjustable shock absorbers with piggyback cylinders and high/low speed compression to soak up the bumps.
It's no use going fast if you can't stop so Aprilia has fitted Nissin radial-mount callipers at both ends, on 270mm front and 240mm rear petal discs.
Aprilia took a chance following the 450 and 550 V-twin route while everybody else stayed with singles The gamble paid off, though, with the smooth-tyred versions taking four Supermoto World Manufacturers' and Riders' championships in the last three years.
The Aprilia RXV and SXV, 4.5 and 5.5 models start at R78995 for the smaller enduro version and go up to R81995 for the 550cc, street-legal SXV 5.5, complete with six-month warranties.