For decades Suzuki has been building class leading performance based Supersport bikes with our GSX-R range, and muscular aggressive street bikes. In recent years we’ve combined these skills and experience to create the GSX-S line, a range of bikes with Supersport derived engines and performance, but harnessed in aggressive naked street bikes for a stripped back look and street focused performance. It began with the GSX-S1000 in 2015, then came the GSX-S750 and now an all new start point for the GSX-S family comes the stunning GSX-S125.
The power plant for the new GSX-S125 is a single cylinder, liquid cooled, DOHC (Double Over Head Cam) with 125cc. It powers the GSX-S to great performance on the streets and a lot more besides. The engineers behind the GSX-S series have been perfecting engines for over 30 years, and this is their latest masterpiece. In the 125cc class the GSX-S125 has the best power to weight ratio, the best torque to weight ratio and the best acceleration. So the rider can enjoy the most fun and excitement, every corner, every straight and every ride. This level of performance is well known for a GSX-R and now a GSX-S too, but beyond the power and acceleration there is even more, this engine is also extremely fuel efficient as well, so you can travel further on each tank of fuel before its time to re-fill.
There is a science to building high-performance engines, and the GSX-S125’s DOHC engine is a perfect example of how to make a lot of power out of a very efficient and compact power plant. The objective is combustion efficiency, optimal balance of the sporty engine character and fuel economy. There is a connection between the GSX-S125 and the race proven four cylinder GSX-R600 sold around the world, because the GSX-S125’s single cylinder is almost one quarter of a GSX-R600. Although Suzuki engineers experimented with different bore and stroke figures to find the most efficient combination for the GSX-S125, the two engines both use an over-square design, with a larger bore and a shorter stroke, and have a similar bore x stroke ratio. The GSX-S125 engine displaces an actual 125cc from a 62mm cylinder bore and a 41.2mm piston stroke. The larger bore makes room for two 24mm intake valves and two 21mm exhaust valves, set upright at narrow angles to improve the shape of the combustion chamber, increasing the compression ratio, performance and fuel economy. The cylinder bore is plated with Suzuki’s own race-proven nickel-phosphorus-silicon-carbide bore coating known as SCEM (Suzuki Composite Electrochemical Material). An aluminium cylinder plated with SCEM weighs much less than an aluminium cylinder fitted with a conventional, pressed-in cast-iron liner, while also reducing friction and improving durability, ring seal, heat transfer and the engine’s ability to maintain consistent high-power output.
An effective liquid-cooling system with a large radiator helps keep the engine at the optimum temperature, producing consistent performance and maximising fuel efficiency and mileage. The engine makes its high horsepower and reaches its generous torque, delivering strong, effective power across a broad rpm range. And the GSX-S125 comes with a smooth-shifting 6-speed transmission and an electric starter.
The GSX-S125 features advanced electronic fuel injection, which delivers fuel based on what the rider is doing with the twist-grip throttle as well as input from sensors monitoring engine rpm, intake air pressure and temperature, exhaust oxygen content and coolant temperature. To improve intake efficiency, throttle response, and engine power throughout the rpm range, the GSX-S125 has a 32mm throttle body. A dual-spray, four-hole injector aims the spray from two holes directly at the intake valves. Ample intake air is supplied by a large-capacity airbox and efficient filter. The accurate electronic fuel injection system contributes to the GSX-S125’s outstanding fuel efficiency.
Advanced Electronic Fuel Injection
Efficient Liquid Cooling
The chassis design of the GSX-S125 is light and compact, giving the rider ultimate control on the streets for a fast and agile ride. For a street bike low weight is key, this helps deliver a bike with responsive and rewarding handling as well as added confidence on the street. The Engineers behind the GSX-S125 have created the lightest bike in the 125cc class, giving the rider the edge over the competition. As well as being the lightest machine in class the GSX-S125 also has the lowest seat height too, making an unbeatable combination for accessibility for all types of rider, while still maintaining an aggressive street look with easy riding position. The low seat height means most riders will be able place both feet securely on the floor for added confidence, while the light weight makes the bike easy to manage both on the move and for slow speed manoeuvers.
Contributing to the bikes low weight are the 10 spoke cast aluminium wheels. Having light weight wheels helps ensure great handling, for a ride that’s fun and a machine that goes exactly where you want it to. The slim design of the spokes also adds to this GSX-S’s aggressive street looks, along with the sporty petal type brake discs front and rear.
The GSX-S125’s confidence-inspiring stability, nimble handling in turns comes in part from its steel-tube backbone frame, which combines optimal torsional rigidity with light weight. This helps the GSX-S’s impressive chassis specification of; compact 1300mm wheelbase, 133 kg ready to ride kerb weight, and a low seat height of just 785mm.
The Anti-lock Brake System (ABS) is the latest Bosch ABS 10 base unit, which is the lightest and most compact two-channel ABS system on the market. The pro-active system monitors wheel speed and immediately intervenes when imminent wheel lock is detected-before actual lock-up. The compact ABS system as installed on the GSX-S125 weighs just 0.59 kilograms. *The sporty-looking petal-design 290mm front disc works with a dual-piston caliper and the 187mm petal-design rear disc works with a single-piston caliper, both delivering excellent braking performance.
*ABS is not designed to shorten the braking distance. ABS cannot prevent wheel skidding caused by braking while cornering. Please drive carefully and do not overly rely on ABS.
Light, Compact Chassis
Light Aluminium Wheels
The GSX-S125 features a convenient easy start ignition system with a shutter-key lock system. The key fob carries a unique, random magnetic code pattern which opens the shutter when the fob is lined up and pushed into a receiver on the ignition lock cover, and the ignition key can then be inserted into the lock and the ignition turned on. Once the key is inserted into the shutter-key ignition lock and turned to the running position, the system automatically starts the engine with one touch of a button mounted on the handlebar; there is no need to hold the starter button down until the engine fires. The shutter can be easily closed by pushing a button once the ignition is turned off and the key has been removed.
Suzuki Easy Start System
Shutter Key Lock Open
The GSX-S125 has exciting, aggressive style that transforms it into a rolling work of motorcycle art. It starts at the front with a modern headlight cowl and instrument module, and continues with a sculpted fuel tank and extended upper side cowlings, plus a lower engine cowling. The tail section and side panels extend forward and reach underneath the fuel tank, unifying the design. And frame covers add distinction and substance to the overall look. The sleek, compact bodywork pieces not only look great, they are also lighter than the bodywork used by competitors, and make it easier for the rider to manoeuvre through traffic jams.
The GSX-S125 features vertically stacked LED headlights, with the low beam above the high beam, and position lights on each side of the headlight. The GSX-S125’s LED headlights are bright and compact, lighter and longer lasting compared to conventional halogen-bulb headlights seen on competing machines. Because LED headlights use about 15% of the electrical power required by conventional bulbs, less engine power is needed to run the motorcycle’s alternator, improving acceleration and fuel economy. The LED license plate light on the rear fender is light and compact and much more durable and vibration resistant than the conventional bulb lights installed on competing 125cc machines.
The Suzuki GSX-S125 has a full LCD instrument panel set in a modern dashboard, framed by turn signal, neutral, hi-beam, coolant temperature, malfunction indicator lamp (MIL), ABS, and programmable engine-RPM indicator lights. The bright LCD panel includes a segmented-bar tachometer across the top; a digital speedometer; a gear position indicator; a digital clock; a digital odometer with dual trip meters; an average fuel consumption meter; a fuel gauge; and an oil change timing indicator.
Styled for Street
|Engine capacity||124cc||Engine||4-stroke, 1-cylinder, liquid-cooled, DOHC|
|Bore||62.0mm x 41.2mm (2.4in x 1.6in)||Compression ratio||11.0 : 1|
|Lubrication||Wet sump||Ignition||Electronic ignition|
|Fuel System||Fuel Injection||Transmission||6-speed, constant mesh|
|Power||11.0 kW @ 10000rpm (15PS)||Torque||11.50Nm @ 8000rpm (8.48lb.ft)†|
11.0litres (2.4 UK gallons)
4-stroke, 1-cylinder, liquid-cooled, DOHC
62.0mm x 41.2mm (2.4 in x 1.6 in)
11.0 : 1
6-speed, constant mesh
Telescopic, coil spring, oil damped
Link type, coil spring, oil damped
†Power and torque conversions to imperial/metric units (in brackets) are approximate and included as a guide only.
|34 monthly payments||£80.56|
Includes VED and First Registration fee
|Total amount of credit||£2772.00|
Included in the final payment
|Total amount payable||£3400.16|
|Duration of agreement||36 months|
|Annual Percentage Rate||3.0%|
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