The difference a pipe can make

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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

  • jason

    I would consider a lot more aftermarket exhausts/slipons if they improved the sound without being so much louder. No need to wake up all my neighbors when I leave for work in the morning.

    • Sean Smith

      That’s probably my favorite thing about these slip-ons: They work amazingly well and the people around you don’t have to know how much fun you’re having.

    • Wereweazle

      Most exhaust manufacturers will list a decibel level for your bike. Just look for one similar to the stock can.

      • aristurtle

        Also remember that bels are a logarithmic scale; +10 dB means that it is twice as loud.

  • zipp4

    Any sound clips?

  • Brian

    Absolutely correct. It even works on scooters. I have a Piaggio MP3 250. With the othe performance mods I did (new variator, Dr Pulley sliders, my akrapovic can just makes everything work that much better. One little known fact about Akrapovic Exhausts. If your exhaust is for the street, they now weld the DB killer in place. No more can you easily interchange it. Still Love what my new can does for my little scooter.

    • donniedarko

      Is there a mod you can do to make it taken in and out easily Brian?

      • Sean Smith

        It’s called the grinder mod. You simply use a grinder to cut the weld, then use a nut and bolt to re-attach the db killer. Or just leave the thing in place since you’ll probably need a different map to make more power.

  • http://greatjoballweek.blogspot.com/ Case

    I don’t know anyone that isn’t a big fan of Akrapovic pipes. Pricey but excellent.

    On the subject of loud pipes, I hiked through part of Santiago Canyon with The Girl this Sunday afternoon. It isn’t far from Cook’s Corner, which is very popular with the ride-it-to-park-it pirate crowd on the weekends.

    We exited the main road and followed the trails back into the hills. The only thing interrupting the quiet of the walk was the sound of every. fucking. bike. dragging itself up a hill two miles away. It was absurd. If I lived there I would go bananas.

    • Beale

      I ride my dual sport up there a lot and have been progressively running quieter and quieter exhausts. I don’t want to be the asshole who disturbs the sound up there. I can hardly wait until we have electric trail bikes with serious range so I can ride up to deer without spooking them.

      • noone1569

        “Hey, hunny, watch me slap this deer on the ass while pulling a wheelie!”

        • Beale

          Exactly. What could go wrong?

        • matt

          that’s awesome. YouTube called, they are waiting for your upload.

  • bluemilew

    Can someone explain to me why the torque and hp curves don’t intersect at ~5000 rpm? I realize the scales are different but I thought it was generally accepted that hp=torque*rpm/5252.

    • http://www.facebook.com/beastincarnate Ben Incarnate

      I believe it’s because there are different y-axis scales for torque and HP on this chart, rather than one scale

      • Sean Smith

        Correctemundo. They should meet at 5252, but Akrapovic pulled them straight from their funny dyno and they don’t quite look right.

  • http://www.muthalovin.com the_doctor

    I like the look, and from the story, they sound subtle, so that is great. I do honestly feel bad waking the neighborhood up at 6:50 when I ride, but I feel fine when Suzy SUV hears me and doesn’t mow me down.

    • John

      There is definitely something to be said for slightly louder exhausts making one’s presence known on the road. I’ve always been a pretty big fan of not dying…

      • http://worldof2.com/ jpenney

        I’ve had bikes of all different sound levels and that has ZERO influence on the car drivers, they are simply tuned out of the driving experience. Between the sound deadening and the infotainment (phones included), no amount of noise, visibility, etc. is going to really make a difference.

        Assume you are invisible and inaudible.

        • SamuraiMark

          +1

          I’m a pretty attentive and responsible cage driver driving a relatively un-soundproofed people-mobile. I can’t think how many times I’ve not noticed open-piped Harley’s on the highway until they were right on top of me. If the loud pipes are in front of you, that’s certainly noticeable. But otherwise, ‘loud pipes save lives’ is BS. More likely to inspire road rage.

          Now, if you’ll excuse me I just need to finish up a bit of shopping here … trouble deciding between Akro, Two Bros, or Scorpion cans. Or maybe Devil.

        • http://lightsoutknivesout.tumblr.com/ Scott Pargett

          I agree mostly with cars being generally oblivious to everything, unless it’s directly in front of them (even then it’s a coin toss). But it has a big affect on other hazards in a city environment such as bicyclists, pedestrians, and critters… all eager to dart into your path suddenly.

          Was a big problem on my Street Triple with the very quiet stock cans. Aftermarket cans put that to a quick end. It was unbelievable how many things were jumping in front of me beforehand.

          Plus I saw some nice performance gains in hp, a ton of high mounted weight shaved, and a really nice aesthetic gain. They are on the loud side, though… no debate there.

  • http://www.twitter.com/wessilerfanclub a hipster

    Those akro’s are rad and I fully believe the performance benefits, but you must have been drunk when you listened to the exhaust on that dorso. It prob is the best sounding bike I’ve ever heard.

  • http://www.facebook.com/beastincarnate Ben Incarnate

    On the Z1000, the slipons are the same price as the full system. The full system more than doubles the performance and weight reduction, but it’s also about 4x the volume. Plus, it realistically demands a fuel controller.

    A quandary like that is why I haven’t done crap with the stock exhaust yet.

    • http://www.facebook.com/beastincarnate Ben Incarnate

      …correction, it’s a bit less than 2x the volume of stock, but only 1 dB higher than the stock Dorso 750.

      Then again, Akrapovic claims all of their systems run fine without a fuel controller. So, maybe the full system would be okay. Le sigh. First world problems.

  • http://www.pedalgents.com holdingfast

    *whispering(sorry to be that guy but you meant tail as opposed to tale – everyone knows, everyone read past it because who cares, but …just sayin)

    • Sean Smith

      I blame my editor…

  • Maxwell

    Im assuming those HP/TQ figures from Akro’s dyno were with proper fuel mapping changes in place no?

    • Sean Smith

      Indeed. Which is to say, stock mapping. They built the pipes so that they’d bolt on and make power without having to adjust the computer. The guys over at Akrapovic are pretty smart.

  • doublet

    Man. I really feel like I want one of these Dorso 750′s. A friend of mine works at a dealership and that was realistically my ‘first impression’. In person, the way nature designed it. Now, I’m looking for a reason to talk myself out of being smitten. Have you guys ridden a 750?

  • Paul

    anyone have a view whether an akrapovic upgrade would have similar impact on the dorso 1200?

  • Mihovil Anic

    Just a quick question. I just got my Shiver ABS and I noticed that the stock exhaust is heating up the seat (outside temp was 10 degrees Celsius). I’m affraid it’ll cook my backside in the summer.
    Did anyone notice if Akrapovic exhaust is also heating up the seat or it addresses that issue on top of sounding great?

    Thanks