The difference a pipe can make

This Aprilia Shiver 750 and its similarly styled stablemate, the Aprilia Dorsoduro, are two very nice looking motorcycles, with one exception — they both suffer from a significant case of junk in the trunk. The stock exhausts, tasked with quieting the booming of two large cylinders, are simply huge. Aprilia’s gone through significant trouble flattening the profile of the cans so the tale looks slim side-on, but view either bike from slightly above and to the rear and things start falling apart. Then a Shiver with Akrapovic pipes showed up in our garage...

Now, we’re not typically ones for aftermarket exhausts. Partly, that’s because we ride very, very fast and don’t like to advertise that fact in the moment. It’s also because the anti-social nature of our two-wheeled pastime/passion/lives has begun to grate. People’s number one complaint about motorcycles is the noise, so it stands to reason that being quiet is the best thing you, I or anyone can do for motorcycling.

Having said that, in stock form, the Shiver and Dorso simply sound anemic. The muted put-put-put is more commuter appliance than Italian v-twin. These Akrapovic slip-ons cure that without going all anti-social. They’re loud enough for you to hear some engine, but someone enjoying an episode of Two And A Half Men won’t spit their carbonated high-fructose corn syrup all over their flat screen when you ride by. According to Akrapovic, the decibel level — 96 — is identical to the stock pipes.

The Akrapovics improve the Shiver, but the difference on the Dorsoduro is night and day. From portly to purposeful in two bolts and a couple of springs.

Aprilia builds a good bike, but Akrapovic makes it better. With the upgraded exhaust, there's something about the sound and character of the motor that evokes what could be described as essential motorcycle-ness. On the Shiver, the peak power increase of 3.4 (81.2, up from 77.8 on Akra's dyno) isn't spectacular, but it is significant. The real news is the torque curve between 3000 and 6000 RPM. The factory pipes cause a sharp torque spike before 3000 rpm, after which torque rapidly drops before rising and then stagnating between 4000 and 5000.

The slip-ons smooth this out while also adding significantly more torque. That's a big deal because the gearing has you cruising between 3000 and 6000 rpm in 6th just about all the time.

The Shiver has other redeeming qualities too: good brakes, a well balanced chassis, smooth easy wheelies on command, and just enough heat coming through the seat from the undertail pipes to keep you warm in jeans. Add a street-legal Akrapovic and suddenly you can add the word “exciting” to that list of qualities.

Akrapovic