Misano Adriatico, Italy - Ducati’s V4 Desmosedici is unarguably the most powerful engine in MotoGP, consistently recording the highest straight-line speeds on Grand Prix circuits around the world.
Now the company, admitting that it has taken the L-twin concept about as far as it can go, has used the experience gained from Grand Prix racing to develop its first standard production V4 engine - the Desmosedici Stradale* - to power the next generation of roadgoing Ducati superbikes.
The first of these, the new Panigale V4, will be showcased at Mllan’s international motorcycle show in November, with a long-stroke (81mm x 53.5mm) version of the new engine, giving it a displacement of 1103cc, for more midrange power and more torque across the rev-range.
Ducati quotes ‘more than 155kW’ at 13 000 revs and ‘more than 120Nm’ all the way from 8750-12 250rpm. There’s also a higher revving short-stroke R version on the stocks with the same 81mm bore (the biggest allowed in MotoGP) but less than 1000cc capacity, making it legal for World Superbike racing; the factory plans to homologate the Panigale V4 R in time for the start of the 2019 season.
The barrels are inclined at 90 degrees for perfect primary balance without heavy, power-sapping balance shafts - but the crankpins are offset at 70 degrees for a ‘big bang’ effect. The result is two pairs of power impulses - bang-bang, bang-bang - which has been shown to generate a more linear power curve and improve traction coming out of corners.
It also gives the V4 that signature lazy, droning soundtrack - and nobody at Ducati will tell you that isn’t an important selling point for the new bike.
As on the MotoGP machines, the crankshaft turns backwards, while the clutch and gearbox turn forward. That’s supposed to reduce the overall gyroscopic effect and make the bike faster and more agile when changing direction - but, as everybody who has ridden one has testified, slow steering is in fact the Ducati MotoGP bikes’ Achilles heel.
V-engines tend to be long; packaging them in a compact sports or racing frame can be a problem. This one has been tilted three degrees to the rear, to bring the swing-arm pivot (which is on the gearbox casing, a Ducati tradition) further forward, and make space for larger radiators in front.
Needless to say, the new engine is designed around Ducati’s signature desmodromic** valve system, using dual overhead camshafts per bank and four valves per cylinder. It also has variable-height intake horns - a first for a production engine from this maker - over four 52mm oval throttle bodies, each with one fuel-injection nozzle above the butterfly and one below it.
*
For those of us who don't speak Ducati, DesmoSedici
is a portmanteau word meaning 'Sixteen Desmodromic Valves'; Stradale
simply means 'Road'.
**Desmodromic
is derived from two Greek roots - desmos (controlled) and dromos (course), a system made famous by Ducati in which the valves are both opened and closed by cams and rockers.