Monday

2012 APRILIA SHIVER 750 GT ABS Sportbike

WHEN MCN COMPARED Aprilia’s then-new Shiver middleweight 750 sportbike to Triumph’s 675 Street Triple back in August 2008, we enjoyed two middleweight “naked” bikes with a lot of performance per cubic centimeter but found both of them could benefit from better suspension. Triumph responded in 2010 by introducing its Street Triple R with fully adjustable suspension, which instantly transformed the bike into a seriously fun backroad sporting weapon for $9499.

When we learned that Aprilia planned to produce a new-andimproved Aprilia Shiver 750 GT ABS for 2011, we began wringing our hands in anticipation. After all, the Shiver had been our comparo winner, and since we already loved its smooth, free-revving V-twin engine and its rock-stable chassis, we imagined how the Dorsoduro’s fully adjustable fork would make the Shiver 750 GT ABS even more attractive. So, we grabbed a test unit as soon as it was available and subjected it to our usual testing regimen. Unfortunately, we didn’t get our wish, as the 2011 Shiver GT ABS retains the original’s non-adjustable front legs. In the end, we can confirm that Aprilia Shiver has been updated, but has it been significantly improved?

2012 APRILIA SHIVER 750 GT ABS
  
Engine & Transmission
Despite its mid-range ranking in Aprilia’s hierarchy of high-performance V-twins and V-fours, the Shiver’s liquid-cooled 90° V-twin was a true benchmark engine for the Italian company. Introduced in 2008, it was the first engine to be produced entirely in-house by Aprilia, which had relied on Rotax in Austria for all its motors previously. This relationship ended for good in 2010 as the last motorcycles powered by Rotax-built 60° V-twins reached the end of the Noale assembly line. In the future, all Aprilia engines, as well as the forthcoming new 1200cc version that will power Dorsoduro 1200, will be built in-house.

The Shiver 750 GT ABS was one of the first motorcycles to utilize flyby wire throttle technology and offer multiple driving modes. Its three fuel/ignition maps; Sport, Touring and Rain, progressively “detune” the engine by altering throttle response and/or cutting horsepower depending on the mode chosen. The rider’s twistgrip
inputs are sent to the Marelli fuel injection’s ECU, which monitors engine rpm, gear position, throttle position and rate of throttle movement, temperature and atmospheric pressure to calculate the optimum spark timing and fuel delivery to the Shiver’s twin 52mm throttle bodies.

2012 APRILIA SHIVER 750 GT ABS
2012 APRILIA SHIVER 750 GT ABS
Although nothing in the EFI has changed since 2008, there’s still a lot to like in the Shiver’s DOHC motor, which uses a combination of timing chains in the lower end and gears in the cylinder heads to actuate the Shiver’s four valves per cylinder. This cam drive arrangement allows for more compact cylinder heads and shorter overall engine dimensions, and Aprilia claims that it also increases timing accuracy. The engine’s 90° layout also naturally quells second order vibration, negating the need for balancing shafts, thus saving weight and reducing drag inside the engine.

Once underway, the Shiver 750 GT ABS transmits its power through a smooth, precise and slick-shifting 6-speed transmission and the clutch action is smooth and silky, no matter what driving mode you’re in. Our only nitpick is that the Shiver’s transmission is geared taller than its supermoto-styled sister, the Dorsoduro 750, which deletes the Dorsoduro’s edgy hot-rod character from its personality. The internal ratios are identical, but the Shiver has a slightly taller 1.75:1 primary ratio and a two-tooth smaller rear sprocket (the Dorsoduro has a 1.87:1 primary and a 16/46 final drive). The changes hurt the Shiver’s acceleration while lowering cruising rpm at 65mph, from 4970 on the Dorsoduro to 4700 on the Shiver. Gas mileage is much improved, however, from an average of 36.9 mph on the Dorsoduro to 43.8 on the Shiver.

2012 APRILIA SHIVER 750 GT ABS
2012 APRILIA SHIVER 750 GT ABS

Chassis, Suspension & Handling
During our recent comparison between the Ducati Hypermotard 796 and the Aprilia Dorsoduro 750, we praised the latter’s stability and precise steering, which was so delightful that it virtually erased the Dorsoduro’s 50-lb. weight disadvantage to the smaller, lighter Duck. As the Shiver shares the same modular steel trellis/cast aluminum frame, near identical rake and trail (25.7°/4.29" vs. the Dorsoduro’s 25.8°/4.25") and actually puts slightly more weight on the front wheel (48.3% vs. 47.3%), we expected it to handle about the same as its supermoto-styled sister.

No such luck. At low speeds, the Shiver handling is shockingly light much quicker than its 56.7" wheelbase and 489-lb. wet weight might suggest. We immediately tried reducing rear preload, to add a bit of what felt like inadequate trail, and found that, indeed, it made a noticeable difference. However, no matter what we did with the rear preload and rebound adjusters (the only adjusters offered at either end), we never found a setting that permitted the chassis to take a reassuring “set” at mid-turn. Although its straightline stability was adequate at higher speeds, its front end feedback was AWOL and multiple mid-turn corrections were the norm. This lack of feedback could shake rider confidence when negotiating fast sweeping curves, especially on rippled pavement where the Shiver’s front end would exhibit a particularly nervous feel.

The culprit appears to be the Shiver’s non-adjustable, 43mm, male-slider cartridge fork. We had hoped that the model updates would include a preload- and rebound-adjustable fork like the one found on the Dorsoduro, but Aprilia clearly meant to keep the Shiver’s MSRP below $9000, and the non-adjustable fork is a cost-cutting move. Unfortunately, that leaves the Shiver rider to deal with factory-set spring and damping rates that don’t compliment the chassis. The fork offers 4.7" of front wheel travel that feels firm on the compression stroke but rebounds too quickly for our tastes. Our recommendation to owners of the new machine would be to take it a reputable suspension tuner, who could probably transform the bike’s
handling with the proper changes for less than $200.

The Shiver 750 GT ABS Sachs shock, on the other hand, does a reasonable job of controlling the rear end. Mounted laterally to the right side of the swingarm to free up space under the seat for the Shiver’s massive 2-into-1-into-2 exhaust system, it provides 5.1" of travel. Like the fork, its shock spring was too firm for our tastes, but making adjustments is easy as the preload collars and rebound adjuster are right out in the open.

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