These motorcycles don’t come around very often, but when they do, the term “instant classic” seems befitting. The Aprilia RSV4 Factory and the Ducati Desmocedici are two machines that qualify.

Ducati’s Desmosedici is certainly an instant classic, as it’s the only machine ever offered to mimic the formidable 990cc era of MotoGP, built in conjunction with Ducati’s MotoGP effort, and is the closest thing to a grand prix replica yet built for the street. The limited-production Desmo combines a hellacious powerband and light weight to make it desirable to every sportbiker, but its $70,000 price tag kept it out of reach to people not named Jay Leno and Tom Cruise. Our review of it can be found here.

Aprilia’s RSV4 Factory delighted us after the first few miles, and our fondness continues unabated. Its wonderful V-Four engine sings like an operatic banshee, and it’s so compact that it feels almost like a 600. Just look at Max Biaggi’s maiden World Superbike title last year aboard the RSV4 Factory as proof of its capabilities. And true Italian beauty that’s not bred from Bologna is a feat in itself. Check out its review here.

Perfection, you say? Not to Kaming Ko.

Loyal readers of MO should be well familiar with the name. The long-time friend of the site, loyal test rider and all-around good guy can never leave well enough alone, whether it’s a lawnmower, weed wacker, or in this case two of Italy’s finest. To Kaming, it can always be a little better. Yes, readers, both the bikes you see here belong to Mr. Ko, and he took the time (and spent the money!) to give each machine his personal touch. Best of all, he let us ride them when he was done. Did we mention he’s a good guy?

Aprilia RSV4 Factory... Upgraded?

We’ve made no secret here that we’re big fans of the stock RSV4 Factory. So really, what could Kaming possibly do to make it better? If the modification list is any indication, not much. First off is a full titanium Akrapovic exhaust system and ECU re-map ($1893). Next, the stock wheels were ditched in favor of a set of OZ forged-magnesium wheels ($5200). Those wheels were then fitted with sticky Dunlop D211GP tires in a 120/70-17 front and monstrous 200/55-17 rear ($419/set).

Our original plan was to let each bike stretch its legs at one of the few tracks in Southern California with a sufficiently long straight section: Auto Club Speedway. Unfortunately the timing didn’t work in our favor. Instead, we brought each bike to Buttonwillow Raceway Park to ride with our friends at Let’s Ride Trackdays. While the tighter confines of Buttonwillow certainly weren’t ideal, it would still prove useful to see how much of a difference each upgrade made to each bike.

The Aprilia was an interesting case, as our testers had developed a love for it during our All-Vee Literbike Shootout from last year. With an already well-honed package, the additional hardware thankfully made one of our favorite bikes even better — except in one key area, which we’ll get to in a moment. We’ve noted before how agile the chassis is; direction changes are executed on a whim with stability throughout the turn. Now with the OZ wheels fitted, direction changes are made even quicker than stock – so much so that we had to adjust our turn-in markers on the track to compensate.

“It tips into a corner really easy,” says E-i-C Kevin Duke. “It’s so compact and responsive, it feels like it should be in a different class to the Desmo.”

As for the Akrapovic exhaust, the RSV4 undoubtedly sounds fantastic, with a similar growl to the Desmo but with a different tone. The surprise, however, came when we put the bike on the dyno. Our initial dyno run recorded the Aprilia making less horsepower than the standard bike we tested last year. Confused, we sought help from some world-class tuners in the area — some with AMA credentials on their resume — and even Aprilia’s U.S. headquarters to figure out why the bike was down on power. After more than 20 dyno runs using every combination of exhaust pipe and ECU mapping imaginable, the end result was still the same: Kaming’s RSV4 Factory with Akrapovic exhaust still made less peak horsepower than our stock test bike last year - 148 horsepower vs. 150.

“The dyno results were a little disappointing, but the engine’s power delivery on the track is very accommodating and definitely doesn’t feel slow,” says Duke. “Unless the Desmo is really wound out, the RSV4 can beat it down a straightaway.”

Next Page...Ducati Desmosedici — All Show and No Go?

Ducati Desmosedici

Ducati Desmosedici — All Show and No Go?

As for the Desmo, the list of upgrades is a little longer than the Aprilia. With stock wheels the tire choice is limited to a specific Bridgestone rubber, made in cooperation with Ducati, because the stock rear wheel is 16.5 inches. There are aftermarket adapters out there to fit a 17-inch Ducati 999 rear wheel and therefore have access to a wider range of rubber, but Kaming wouldn’t settle for that.

Instead, he fitted his Desmo with 17-inch BST carbon fiber wheels ($1695 front, $2695 rear) to accommodate the same Dunlop tires as the Aprilia. But while he was at it he went crazy and installed ceramic wheel bearings ($395), and a host of titanium bits including sprocket studs, nuts, and lock washers. Why all the trick lightweight bits? “I don’t know. They sounded good at the time, so I bought them,” says Kaming.

We’ll admit, once the aura and panache of the Desmosedici wears off, it shares something in common with virtually every motorcycle: it could use improving — mainly to the suspension. The standard spring rates work well for a top-flight racer, who generally prefers stiffer rates than us mortals. But since neither Kaming nor we possess that kind of skill, Mr. Ko felt the need to replace the stock 8.0 kg/mm rear spring with a 7.0 kg/mm unit ($713.50).

It’s money well spent, we think. The softer spring absorbed more of the road imperfections around “Bumpywillow” and was generally well accepted among all of our testers. Also well accepted were the carbon fiber BST wheels and Dunlop race rubber. It’s hard to pinpoint which of the three upgrades deserves the most credit for the Desmo’s improved handling, but overall — and at our respective speeds — it steered quicker with a more compliant ride.

“It now steers so much better than stock,” raves Duke. “The BST wheels are even lighter than the mag stockers, and their traditional 17-inch sizes make its handling so much more linear and allows the use of any grippy sportbike tires. It’s much more composed while leaned over in a corner.”

The Desmo has a massive top-end hit that catapults the bike down every straight, but its performance on the dyno was a bit disappointing. Not only does the Desmosedici make less overall torque than the Aprilia, but it isn’t until 11,000 rpm that it surpasses the Ape in peak horsepower as well. Take a closer look and you’ll also see that the Ducati is far from linear in the way it builds power, unlike the RSV4. But you’ll never notice that from the saddle. During our track testing, the Desmo seemingly went from a standstill to light speed the moment the throttle was cracked. 

One area that wasn’t touched, but one we were still mixed about, is the Desmo’s rider triangle. The clip-on bars are a stretch from the saddle and the pegs feel surprisingly low for a sportbike. Overall comfort with the narrow seat took some getting used to, which some were able to do and others weren’t. Ground clearance was never a problem, though hanging off the bike mid-corner felt awkward to some.

“This is likely the only GP motorcycle I’ll ever ride, so my basis of comparison is limited,” says Pete. “But compared to ‘normal’ sportbikes the Desmo feels strange, almost unnatural. Though it’s still cool as heck to ride!”

Worth The Money?

If the numbers don’t bother you, the upgrades to the Ducati transform the bike from a raging bull to a relatively manageable beast. Even though the power figures aren’t particularly impressive, as a total package it’s much better than stock in our minds. As for the Aprilia, while we can’t explain the power deficit, that’s not to say every aftermarket exhaust will deliver the same results.

When it’s all said and done, are the upgrades worth the money? The changes to the Ducati transform it to a machine worth living with, while the anomaly that is the Aprilia makes an argument that spending a ton of cash does not automatically make a motorcycle better.

Either way, these are two of the coolest sportbikes we’ve ever ridden.

Related Reading
2011 Aprilia RSV4 Factory APRC SE Review
2010 Literbike Shootout
2008 Ducati Desmosedici RR Review