ROAD TEST HYOSUNG ST7
WORDS: Michael Esdaile PICS: Geoff Osborne
Having established itself in the small to medium capacity classes Hyosung has signalled its intention to move up the cc scale with this month’s cover bike, the ‘lightheavyweight’ ST7 cruiser. KIWI RIDER 25
ROAD TEST HYOSUNG ST7
100 although the ST7 would happily run at 110-120km/h, the only limitations being the presence of revenue collectors – and the wind pressure the handlebars expose you to. The ST7’s motor is very punchy from 80 km/h onwards in fifth and at a private test facility we managed (holding on grimly) to achieve 180 km/h. But that’s not the point of a cruiser. Interesting, though, that the motor had the grunt to propel it to that velocity.
t looks good and it’s got a storming engine, but underneath, it’s still a Hyosung.”
I
Hyosung ST7 is totally different, featuring a well ‘over square’ motor with an 81.5mm cylinder bore and a 65 mm stroke.
With this advice, Kiwi Rider Editor Ross MacKay handed me the key to the latest creation to roll off Korean motorcycle manufacturer Hyosung’s assembly lines at Changwon.
With the highest power output by some margin among the 650 to 950cc cruisers, the ST7 is also the lightest, which is why Hyosung calls it a ‘light heavyweight’.
Changwon is near Busan, a city near the southern tip of Korea that is also home to Samsung’s gas turbine engine and selfpropelled artillery making arm, Hyundai’s railway rolling stock manufacturing facility, LG Electronics, and Doosan, a heavy engineering company that makes large diesel engines, desalination plants, large forgings and castings as well as nuclear power plants. Changwon is also where S&T Daewoo is headquartered, making, among other things, vehicle electronics and small arms. Changwon’s exports in 2008 alone amounted to $US 28 billion – more than that of all of New Zealand. So this is no rinky-dink little Asian city. Back to the latest Hyosung, the ST7. MacKay was right, it does have a stunning engine, one that can cruise along in relaxed mode, or blast you down winding roads in almost sports bike manner, depending on what takes your fancy. The 680cc, DOHC, 8-valve, liquidcooled fuel-injected 90° V-twin motor is derived from the tried and tested GV650 motor but sports slightly longer cylinders to match the increased piston stroke that provides the increase in displacement. Hyosung has yet to tell us what else they changed in the motor to give it even stronger bottom-end power than the GV, but our guess is that valve timing and electronic engine management is different. Most cruisers feature ‘under square’ engines (cylinder bores smaller in diameter than the length of the piston stroke) to achieve stump-pulling low rpm torque. The 26 KIWI RIDER
ON THE ROAD With an extensive high pressure weather system extending over the country providing cloudless days (I suppose Hyosung would call that a Natural Hy), the opportunity was too good to turn down. We’d done enough wet weather riding recently so with the 17.5 litre fuel-tanked brimmed, it was off south. Using a circuitous route that took in Bombay, Miranda, Clevedon, Maraetai and back through Auckland, we were able to whiz along the motorway at 120 km/h, attack winding back roads at a bit more than that, putter along the Sea Bird Coast at 80 to 90 km/h soaking up the views, nip through another set of winding roads, then get stuck in stop-start peak hour traffic. Apart from the peak hour part, the ST7 coped with every road condition we tried it on with aplomb. Tall riders found the forward mounted foot-pegs within easy reach but those of shorter in-seam felt the pegs were too far forward. This, combined with the high, wide and pulled back handlebars, puts you in a laid-back (literally) riding position. For the first time we discovered a motorcycle riding position that put the old abs in tension!
On the back roads the ST7 was happy to run anywhere from 80 to 120 km/h in top and with greater ground clearance than most cruisers, it was a while before we found the limits to bank angle. Let’s just say you can roll this baby over in corners like no other cruiser – apart from the Moto Guzzi Bellagio. STOPPING Arriving unexpectedly in a tighter than anticipated left-hander, a quick clamp on the front brake lever combined with a decent push on the rear brake pedal washed off speed easily and quickly, the ST7 snapped over into full bank, and we were through, no drama with grounding out floor boards. Talking about the brakes, there’s a generous single disc up front clamped by a four-piston caliper that provides good feel with heaps of power. Out the back there’s another disc rotor, this one gripped by a twin adjacent piston floating caliper. Now most cruiser-style bikes (not to mention most scooters) have a lot of their stopping done by the rear brake. This is due to a very much rearward weight bias and a low, long chassis that does not pitch as much weight forward onto the front wheel when the front brake is applied as taller, shorter bikes do. So you normally slow cruisers using a generous amount of pedal pressure on the rear brake and a gentle squeeze of the front. Not so with the ST7 though. We discovered early on that using cruiser-type levels of rear brake pressure locked up the rear wheel quite easily so the technique is to use the front harder than usual for a cruiser and press more gently on the rear pedal. Our guess is the ST7’s motor is further forward in the chassis than is the cruiser norm, so there is less weight on the rear tyre.
Through 50 km/h zones the ST7 will run along in top (fifth) gear but is happier in fourth. Anything above 60 km/h though and fifth gear pick-up is fine.
Further strength to this theory came when we snapped the throttle wide open on a damp road, and immediately got the rear Shinko spinning for 50 to 100 metres in the straight line. Fun too…
EASY TIGER!
HANDLING
On the motorway, we had to consciously ease the throttle to keep speed down to
This is not something we delve into in most cruiser tests because these sorts of bikes
You can on the ST7 though. The technique we used was to eye up the corners, roll off the throttle and let the prodigious engine braking (hey, this thing has an 11.5:1 compression ratio after all) wash off the required speed, then turn in on the throttle and let the mid-range surge drive you through and off down the next straight. The only time we used the brakes at all in the winding stuff was to stop the ST7 running into the rear of a P o l i c e car driven by an apparent novice who kept braking in the most unexpected places. Fortunately, the driver got the message, pulled over and let the Hyosung through. OVERALL The only glitch we found in a 300 km afternoon’s fun was the very on-off throttle response in stop-start peak hour traffic when we were down in second (and even first) gear in the evening crawl. We found we were slipping the clutch a little at times to ease the abruptness when the throttle was opened from completely closed at crawling speeds. The other whinge was the indicator switch. Now you may think we are looking for things not to like about the ST7 but the truth is it is the response from hand and foot controls that can nark you about any bike. In the case of the ST7, the indictor switch was stiff and we often had two attempts before we got the flashing light cancelled.
ST7 is an all-new model for Hyosung with little to link it even with impressive 650-size Aquila. Look is classic old-skool US cruiser with a twist while feel has a distinctly sporty edge. Engine is liquid-cooled and fuel-injected with the same bore but a longer stroke than its 650cc class siblings. Build quality is solid but tactile feel (the indicator switch is particularly clunky) is nearer to The Warehouse than it is Barkers. Longer legged riders found the forward-mounted foot-pegs a comfortable reach, but it was a bit of a stretch for shorties. Higher than usual cruiser ground clearance yields good cornering clearance.
That said, brake and clutch feel were very good and it is pleasing to see the front brake lever is span adjustable to suit as wide a range of hand sizes as possible. After 300 km in an afternoon, we had a twinge or two in the gluteus maximus muscles from the very laid-back riding position but apart from that, we were ready to go again. After a fairly spirited performance all afternoon, the ST7 swallowed 15.25 litres of fuel to return consumption figures of 5.02 l/100km (19.92 km/l). And believe it or not we’d expect much better than that if we could have contained ourselves to a more ‘cruiser’ style, but the ST7 was too much fun on a sunny afternoon for that. KR
ROAD TEST HYOSUNG ST7
generally have such cornering clearance limitations you don’t exactly attack the twisties.
SPECIFICATIONS HYOSUNG ST7 ENGINE Type: Liquid-cooled DOHC/4-valve 90° V-twin Displacement: 680cc Compression ratio: 11.5:1 Bore x stroke: 81.5 x 65mm Starting system: Electric Engine management system: CDI Fuel system: Electronic fuel injection Clutch: Wet multi-plate Transmission: 5-speed Final drive: Belt FRAME Type: Tubular steel twin cradle Swingarm: Steel Front suspension: Telescopic fork 41mm Rear suspension: Single preload adjustable coil-over shock absorbers Brakes: Single floating 300mm rotor disc w/ 4-piston caliper front & single 270mm rotor disc w/ two-piston caliper rear Wheels: Cast aluminium alloy 16 in. dia. front & 15 in. dia. rear Tyres: Shinko SRR712 120/90-16 front & 170/80-15 rear DIMENSIONS Wheelbase:1690mm LxWxH: 2480 x 840 x 1125mm Seat height: 675mm Dry weight: 225kg Fuel tank capacity: 18L RRP: $24,995 Test bike: Hyosung NZ Ltd More information: www.hyosung.co.nz GEAR: Helmet: Arai Jacket and gloves: Spidi Pants: Draggin Jeans Silverback Boots: Diadora
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