With new emission norms strangling the engines, motorcycle exhaust systems have become a big problem for bikemakers. They’re bulkier than ever and require tonnes of R&D to limit the emissions/decibel levels, while somehow not playing spoilsport for the power output. In fact, many bikemakers have even hired exhaust companies to do the work for them; for instance, the Honda CBR1000RR-R comes with an Akrapovic exhaust as standard.

Go back two decades, however, and the story takes a 180-degree turn. Don’t get us wrong, bikemakers still paid attention to exhaust systems, not to meet norms, but to make them as good-looking as possible. And when talking about ‘good-looking’, we have to talk about under-tail exhausts. So as a throwback to the golden era, here are five motorcycles with the sexiest under-seat exhausts.

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Honda NR (or NR750)

1992 Honda NR750
Honda
The NR750 was the first four-stroke motorcycle with an under-seat exhaust

The Honda NR750 was the first-ever production motorcycle to feature an under-seat exhaust. It had a chunky tail section (inspired by race bikes) that incorporated two exhausts inside it. In fact, Honda integrated the exhaust so well, you wouldn’t even know it was there unless you looked with a keen eye. Or directly from the rear. The NR750 also went on to serve as an inspiration for the Ducati 916 (that made under-tail exhausts mainstream two years later), as accepted by its designer Massimo Tamburini himself.

Besides this, the NR750 employed a 747cc, V4 engine that produced 120 horsepower at 14,000 RPM via its unique oval pistons and an insane 32 valves. Honda topped this off with handcrafted bodywork (infused with carbon fiber) and a single-sided swingarm–both rarities at the time. There are a dozen other things that made the NR750 way ahead of its time, and you can read them all here.

Yamaha YZF-R1

2006 Yamaha YZF R1
Yamaha
Limited Edition variant of the 2006 Yamaha R1

After a few years with a side-mounted exhaust, the Yamaha YZF-R1 switched to an under-tail setup in 2004. And boy, did it ace it. Unlike its contemporaries (Ducati 999 and Honda CBR1000RR), the R1 featured twin under-seat exhausts tucked under an edgy tail section. The exhaust cans themselves had a slash-cut shape to further elevate the visual experience. The design became a hit in no time, thanks to which Yamaha stayed with the setup for the R1’s next generation too. Bulkier, triangular exhausts took the place of the slash-cut units and helped the R1 stand out against its Japanese rivals who had all switched to side exhausts by then. Over a decade later, the under-seat exhaust variants of the R1 continue to be popular wallpaper options.

Ducati Desmosedici RR

Ducati has had a few under-seat exhaust motorcycles in its lineup. But nothing matches up to its uber-limited Desmosedici RR. First unveiled in 2006, the motorcycle served as a road-going version of Ducati’s proven MotoGP race bike and drew several components from it. Though its 989cc, V4 engine made the most headlines, the exhaust was nothing short of special too. The four headers merged into two outlets that flowed from under the rider’s seat and out of the tail. It had no physical exhaust cans per se, but a closer look at the rear revealed two slash-cut ports which stare dead into your eyes. And then deafened your ears.

To talk numbers, Ducati claimed 180 horsepower from the factory and included a race kit (special ECU and exhaust) to bump this to 197 ponies. This, coupled with its 377-pound dry weight, helped the RR breach 190mph. Curious how Ducati achieved such a low weight? Well, credit went to the carbon fiber body, aluminum engine cases, and Marchesini forged magnesium wheels–the first of their kind at the time.

Honda RC213V-S

2016 Honda RC213V-S
Honda
The RC213V-S has a full-titanium exhaust system

Moving from one exotica to another, we come to the Honda RC213V-S. Like the Desmosedici, the RC took inspiration from Honda’s MotoGP weapon, the RC213V, and came ripe with a plethora of MotoGP-derived componentry. This included a MotoGP-like exhaust with two outlets - one on the side and the other under the tail section - all carved out of titanium. The under-tail unit, together with the sleek tail, had MotoGP written all over it–something no other bike offered in 2017. Another notable detail is the absence of a catalytic converter which ensures utmost power from the engine.

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Speaking of which, the RC123V-S employed a 999cc, V4 engine that produced 159 horsepower in standard trim. Slap on the supplied ‘Sports Kit’, and the number creeps over 215 ponies–plenty for a 170 kg (374 pounds) beast. To further help you obliterate the track, Honda bedazzled the RCV with race-spec Brembos, magnesium wheels, titanium bolts, and a bespoke MotoGP-spec aluminum swingarm.

MV Agusta F4

2007 MV Agusta F4 CC
MV Agusta
Close up of the MV Agusta F4's four-into-four exhaust

Back when the key players were experimenting with twin exhausts, MV Agusta set the record straight with the F4. It flaunted a tushy like no other, ripe with four - yes, four - under-tail exhausts. The stand-out element soon became a staple for MV Agusta, and not even once did the Italian bikemaker deviate from it. Instead, the sports bike aged like fine wine to feature an uber-edgy tail section - complete with four squarish exhausts - for its last iteration in 2017. As for performance, the 2017 F4 came in two variants, RR and R, both with a 999cc, inline-four engine. However, the ‘R’ produced 195 horsepower while the RR belted out 205 ponies.

So out of these five, which one gets you the most excited? Or did we miss any motorcycles? Let us know in the comments.