2021 Middleweight Naked Spec Sheet Shootout

A by-the-numbers look at our six contenders

With the Aprilia Tuono 660 and Triumph Trident 660, we’ve got two brand new middleweight nakeds on the market this year, entering what was already a pretty good field with the Honda CB650R, Kawasaki Z650, Suzuki SV650, and the Yamaha MT-07. Obviously, this calls for us to put all six motorcycles together in a shootout.

John, Troy and Ryan have been putting these middleweight naked bikes to the test, with Evans taking photos and Sean shooting video in preparing this six-model comparo. Of course, with me more than 2,000 miles away up in Toronto, I get the much less exciting task of comparing these middleweights on the spec sheet. I’m not bitter. At least I have the Stanley Cup playoffs to look forward to… dammit.

All right, let’s get this over with (still not bitter).

Engine

The term “middleweight” doesn’t mean the same as it used to. With the bigger bikes now pushing into the 1200-ish range, the middleweight class has grown to cover a wide range of displacements. Just look at our middleweight adventure shootout earlier this year featuring bikes ranging from 689cc to 889cc.

Thankfully, for this shootout, we’re able to wrangle six contenders that are relatively close in engine displacements, ranging from 645cc to 689cc. At the low end, we have the 645cc Suzuki SV650, with the Honda CB650R and Kawasaki Z650 only slightly larger at 649cc. We then have the Aprilia Tuono 660 and Triumph Trident, the two newest models in this shootout, coming in at around 660cc. The Yamaha MT-07 tops this competition with a 689cc displacement, but the overall gap between the largest and smallest engines is pretty narrow.

Among our six battlers, half of them are powered by Parallel-Twins in the Aprilia, Kawasaki and Yamaha. The SV650 mixes it up a bit with a V-Twin configuration, but then we have the three-cylinder Trident and the CB650R’s Inline-Four.

Putting all six bikes on a dynamometer, we start to see some separation between the engines. The Tuono 660 produced the most power with 84.6 hp at 10,500 rpm. At the low end, we have the Kawasaki Z650 with just 61.4 hp at 8100 rpm. Both are Parallel-Twins, with just 10cc separating them, but the Aprilia overpowers the Kawasaki, thanks to its higher rev limit and a significantly higher compression ratio (13.5:1, easily tops in this competition, but much higher than the Z650’s 10.8:1).

The SV650 and MT-07 all hover around 70 hp, with the Trident a little higher at 72.3 hp, which further shows how much a disadvantage the Z650 has in this comparison. The CB650R produced the second highest horsepower with 81.9 hp, but you had to get close to its rev limit to get there. In the midrange, from 5,000 rpm to 8,000 rpm the Honda was at the bottom of the pack before it finally caught up. Though it produced the second lowest peak, the MT-07 offers more power of all six bikes up until around 8,300 rpm.

It was a similar story on the torque curve, with the CB650R having a big dip in the midrange, but this time it wasn’t able to outrun the competition, peaking at 42.1 lb-ft. at 8500 rpm. The Trident, SV650 and Z650 were all fairly close in the midrange while the Tuono 660 didn’t catch up until around 8000 rpm. The Yamaha MT-07 produced far and away the most torque for most of the rev range, peaking with 48.7 lb-ft. at 6300 rpm.

Chassis

The Z650, SV650, MT-07 and Trident each use tubular steel frames while the CB650R uses a twin-spar steel frame. The Tuono stands out with both its frame and swingarm made of die-cast aluminum.

The Kawasaki, Suzuki and Yamaha each use 41mm telescopic forks. The Triumph and the Honda are equipped with inverted Showa Separate Function Forks, but the CB650R gets the slightly better Big Piston version. Aprilia equipped the Tuono with a Kayaba fork, the only one of the bunch with adjustable rebound and spring preload.

The Tuono and MT-07 offer adjustable rebound damping and spring preload on the rear suspension. The rest offer only preload adjustment.

All six bikes offer dual front disc brakes and ABS as standard, but there are still different levels of brake quality. On the lowest tier, we have the Z650 and Trident using two-piston front calipers. The SV650 and MT-07 offer a step up with four-piston calipers, while the CB650R adds radial mount calipers.

The Tuono goes the extra step with a radial master cylinder and steel-braided brake lines (the Trident also has steel-braided lines). The Aprilia is also the only one that offers an optional IMU which enables cornering ABS (our test bike is equipped with this $400 option).

Dimensions

Measuring all six bikes on the MO scales, the Tuono comes in the lightest at just 401 pounds (with the caveat that it was the only one we weighed without mirrors). The MT-07 wasn’t far behind at 406 pounds, followed by the Z650 at 412 pounds. The Trident’s 427 pounds looks relatively porky, but our unit was equipped with accessory grab rails and engine protectors. Even then, it’s still lighter than the 438-pound SV650 and 443-pound CB650R.

The SV650 offers the lowest seat height at just 30.9 inches, followed by the Z650’s 31.1-inch saddle height. The Trident and MT-07 offer identical 31.7-inch seat heights, with the Honda slightly higher at 31.9 inches. The Aprilia offers the highest perch at 32.3 inches. That’s nearly an inch and a half higher than the SV650’s seat.

Price

Looking at the specs sheet, it comes as no surprise with its premium components that the Aprilia Tuono 660 has the highest Manufacturer Suggested Retail Price at $10,499. That’s over a grand more than the second priciest, the $9,199 Honda CB650R. The Trident is next at $8,095, which also makes it the least expensive bike in Triumph’s entire lineup. In this group, however, it falls in the middle above the MT-07 ($7,699), SV650 ($7,499) and Z650 ($7,749).

So, which of these naked middleweight motorcycles is the best? On paper, we can make some assumptions, but we’re going to have to wait for the testing to be done to find out.

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