Zero S — complete owner's guide

The Zero S is built around the air-cooled Z-Force 75-7 interior permanent-magnet AC motor, a clutchless direct drive and a Poly Chain HTD Carbon belt (20-tooth motor sprocket, 90-tooth wheel sprocket) — there is no clutch, no gears and almost no routine driveline maintenance. Energy comes from a Z-Force ZF14.4 lithium-ion power pack rated at 14.4 kWh maximum and 12.6 kWh nominal, managed by a sealed Battery Management System (BMS) and driven through a 600-amp three-phase controller with regenerative deceleration.

Zero sells the S in two forms. The A1 version is power-limited for restricted licences: 45 kW (60 hp) peak, 132 Nm, an 11 kW (15 hp) 30-minute continuous rating under UNECE R85, and a top speed of about 139 km/h (86 mph) max / 110 km/h (68 mph) sustained. The Full Power S makes 51 kW (68 hp) peak with the same 132 Nm and reaches roughly 167 km/h (104 mph) max / 130 km/h (81 mph) sustained. Both use the same 3 kW onboard charger (upgradeable to 3.3 kW), the same chassis and the same Cypher III software.

On the standard EPA city cycle the S is rated at about 248 km (154 mi) per charge, dropping to roughly 182 km (113 mi) in low-speed highway commuting and 162 km (101 mi) in faster mixed highway use. Zero estimates the pack retains 80% of capacity out to around 335,000 km (208,000 mi) of city use.

Almost everything on the Zero S is navigated with the left-hand MODE toggle plus the key switch and motor stop switch. The right grip is the throttle; the right lever is the front brake and the foot pedal is the rear brake. The digital dash shows a central speedometer inside a 12-segment ring, where each segment represents 20 km/h up to a 240 km/h scale, plus four configurable quadrant gauges. You can assign any quadrant to State of Charge, estimated Range, Battery temp, Motor temp, instant or trip efficiency, RPM, Trip A/B or ambient temperature. A separate regen/torque meter shows how much torque is going to (or being recovered from) the rear wheel, and a charge indicator shows remaining energy.

The dash has two main states. The Riding Screen appears when the key is ON, the motor stop switch is in Run and the kickstand is up. The Menu Screen — reached by putting the motor stop switch OFF and/or dropping the kickstand, then pressing MODE for about a second — is where you set Preferences (brightness, gauges, clock, Bluetooth, units, language, automatic updates), read Battery and Performance data, and view stored errors. Hold MODE left to exit back to the Riding Screen.

The warning-light cluster is worth learning before your first ride, because several lights are normal at key-on and only tell you something is wrong if they behave abnormally at speed.

The Zero S ships with five factory ride modes — ECO, STANDARD, SPORT, CANYON and RAIN — plus a CUSTOM slot you shape in the Zero smartphone app. Each mode retunes acceleration, top-speed limit and the strength of regenerative braking, and each has its own dash accent colour. You change modes from the Riding Screen by pressing MODE for about a second, toggling left/right to the mode you want, then holding MODE left for a second to apply it. You can switch on the move, but if the throttle is open the change waits until you close it.

Throttle and braking are linked through regen. Twisting the grip toward you accelerates; releasing it past the zero-torque point engages regenerative braking, which slows the bike and returns energy to the pack. The zero-torque point sits just off fully closed and shifts with speed and ride mode, so if you want to coast freely without regen drag, hold the throttle a hair open at that point rather than snapping it shut. For normal braking, close the throttle and use the front lever and rear pedal.

Cruise control is a long-press function: reach your target speed, press and hold the cruise button for about half a second, and the set speed shows on the dash. It works only between 30 km/h (18 mph) and 144 km/h (89 mph). There is no incremental up/down — to change speed you cancel and re-set. A short press, or touching either brake, drops the current set speed; a long press turns the whole function off.

The Zero S runs Bosch's anti-lock braking with Base motorcycle stability control (Advanced MSC is available as a Cypher upgrade). ABS prevents wheel lock-up under hard braking, but it is not a substitute for good technique and cannot overcome the physics of braking mid-corner. The ABS light is meant to be on at a standstill and should extinguish once both wheels pass 5 km/h. If it stays lit above that speed, ABS is inactive and the bike brakes like a non-ABS machine. A big front-to-rear wheel-speed difference — a wheelie, a burnout or loose gravel — can also disable ABS; to restore it, stop completely, key OFF for about five seconds, then key ON.

Motorcycle Traction Control (MTC) cuts motor torque when the rear tyre starts to spin, and offers four settings — STREET, SPORT, RAIN and OFF — that are selected automatically with each ride mode but can be changed manually by holding the MODE toggle right until the mode flashes, then toggling and confirming. The traction-control light stays lit whenever MTC is switched OFF. Drag Torque Control (DTC) is the deceleration-side partner: it manages regen drag so the rear wheel doesn't slip while you're slowing down. Note that disabling ABS also disables DTC, though MTC keeps working.

Parking Mode is a Cypher III+ upgrade that adds a walking-pace forward and reverse crawl for manoeuvring in tight spots and on slopes. It is not a parking brake. With the bike stationary and the motor stop switch OFF, open the Menu, select Parking Mode, then raise the kickstand and set the motor stop to Run when the dash prompts. Use the cruise button to switch between reverse and forward, and feather the throttle gently. Drop the kickstand, set motor stop OFF, or turn the key off to exit.

The Zero S charges through an onboard AC charger — there is no DC fast-charge (CCS) port on this model. EU bikes use an IEC 62196 Type 2 (Mennekes) socket; other regions use a J1772 (Type 1). The standard onboard charger is rated 3 kW and is firmware-limited to 3.3 kW, which the '+10% Charge Power' Cypher upgrade unlocks. A full charge normally takes under five hours in mild temperatures. Charging simply won't happen if the pack is below 0°C (32°F) or above 50°C (122°F), and above about 43°C (110°F) ambient the charger deliberately reduces current, so hot-weather charges take longer.

On the dash and in the app you get three tools to manage charging. Charge Target lets you cap the maximum State of Charge (0–100%) so the pack isn't left sitting full. Delay/Scheduled charging (app only) shifts charging to off-peak hours and takes precedence over Charge Target. Extended Range Charging — a Cypher III+ upgrade — tops the pack to a displayed '110%' for long trips, and must be re-selected each time you want it. When storing or between infrequent rides, a lower resting charge is kinder to the pack.

Battery care is where Zero is most specific. Never leave the S sitting below 30% State of Charge — a prolonged low charge can damage the pack and void the warranty. If the pack is ever fully discharged, recharge it within 24 hours. In hot weather or after sustained freeway speeds, let the pack cool a few hours before charging rather than charging it hot. Once charging is done, unplug: the pack enters a hibernate mode and self-discharges extremely slowly.

An electric drivetrain has no engine to run in, but the Zero S still benefits from a deliberate first phase. Ride conservatively at first to learn the throttle-and-regen relationship, the real-world range of your commute and how the bike behaves under braking — its light weight and instant torque reward smooth inputs. Because release-throttle regen does much of the slowing, spend your first outings getting comfortable modulating the grip before leaning on the modes with more aggressive power.

For the battery specifically, Zero recommends a calibration routine over the first five charge cycles: let the pack discharge below 5% and then charge it above 95%. This does not change the battery's performance or capacity — it simply lets the BMS learn and report State of Charge more accurately, so your range estimate becomes trustworthy.

Two early dealer or self-checks are built into the schedule. At the initial 100 miles (160 km) and again at 600 miles (1,000 km), the belt tension, throttle operation, kickstand and drive-motor commissioning are verified; the 600-mile service adds wheel bearings, steering bearings and the front brake-lever pivot. These first inspections catch settling and mis-tension early and are, per Zero, the most important services in the bike's life.

With no oil changes, spark plugs, air filter or clutch, the Zero S service list is short, but a few items are non-negotiable. Before every ride, check brake-fluid level, front and rear brake operation, tyre pressure and tread, and the drive belt's tension and condition. The major service falls every 8,000 miles (13,000 km) or 12 months, whichever comes first, and covers a brake-fluid replacement, wheels and wheel bearings, belt tension, steering bearings, all chassis fasteners, the fork and shock, throttle grip, kickstand and a drive-motor commissioning check.

Brake fluid is DOT 4 and must be replaced every 12 months regardless of mileage, because it absorbs moisture over time; Zero recommends a dealer do this since the ABS hydraulic unit complicates bleeding. Two longer-interval jobs round out the plan: repack the steering bearings every 16,000 miles (25,000 km), and replace the Gates carbon belt and inspect the swingarm pivot bearings every 24,000 miles (37,000 km).

The belt is low-maintenance but not no-maintenance. Keep it free of oil, grease and grit, wash it with mild soap and water, and inspect for cuts, exposed tensile cords, cracking at the tooth base or edge beveling (a sign of sprocket misalignment). Correct tension is 62–82 Hz measured with the Gates Carbon Drive app or a tension tester on the lower belt span; too little tension lets the belt 'ratchet' over the sprocket teeth and damages the cords, while too much wears the drivetrain. After adjusting, aim for a 1–2 mm gap between the belt and the rear sprocket face, torque the rear axle nut to 102 Nm (75 lb·ft) and the tension bolts to 5 Nm (4 lb·ft).

The Zero S rolls on 17-inch cast wheels — a 3.50-inch front and 5.50-inch rear — fitted from the factory with Pirelli Diablo Rosso III tyres (120/70-17 front, 180/55-17 rear). Zero also approves Pirelli Angel GT and Michelin Road 5 in the same sizes. Run 36 psi (248 kPa, about 2.48 bar) in both tyres, checked cold — meaning not ridden for at least three hours — and replace a tyre once tread falls below 1.6 mm (1/16 in) or you find cuts, bulges or cord. Fit only matching Zero-approved radials on both wheels; mixing brands or types can upset handling and defeat the ABS and traction control.

Braking is by J-Juan hydraulics with Bosch ABS: twin radial-mounted four-piston calipers on a 320 x 5 mm front disc and a single-piston floating caliper on a 240 x 4.5 mm rear disc, with separate front and rear DOT 4 reservoirs. The fluid level drops slightly as pads wear but must never fall below the LOWER mark — if it does, or if the lever/pedal feels spongy or long, don't ride until it's sorted. Use progressive braking; even with ABS, grabbing the brakes mid-corner can overwhelm the system.

Suspension is fully adjustable at both ends: a Showa 43 mm big-piston separate-function fork with 120 mm of travel and adjustable preload, compression and rebound, and a Showa 40 mm piggyback-reservoir rear shock with 140 mm of travel and the same three adjustments. If you change your load — a passenger, luggage — revisit the settings, and remember suspension sag affects headlight aim.

For any layup longer than 30 days, Zero's advice is to leave the charger connected. After 30 days the BMS automatically enters Long-Term Storage Mode and drains the pack to roughly 80% SoC — the sweet spot for calendar aging. Store the bike somewhere cool; the recommended storage temperature is 10–35°C (50–95°F), and hot storage shortens pack life. The cardinal rule still applies: never let the pack sit below 30%. To bring the bike out of storage, disconnect the charger, key ON, raise the stand and set the motor stop to Run to exit storage mode, then key off, reconnect and charge at least 24 hours to restore cell balance. Check the dash SoC every 30 days in case a tripped breaker or GFCI has interrupted charging.

Cold weather doesn't permanently harm the pack, but it temporarily cuts range — potentially up to about 30% at -1°C versus 27°C — and can trim power and top speed. The pack won't charge below 0°C, so a cold bike needs to warm above freezing (or be brought indoors) before it will accept a charge; if you ride when the pack is below -5°C, put it on the charger above 0°C as soon as you finish. The BMS won't discharge the pack below -30°C at all. Winter garage storage down to -35°C is safe provided the bike stays plugged in. The 12-volt battery has its own heater that activates below 5°C, during which the bike may be disabled for 1–15 minutes until it warms.

When transporting the S, both wheels must be on the trailer or transport device — it should never be towed on one wheel. Secure it upright and switch the motor stop to OFF before pushing or backing it up by hand so the drive can't engage.

The Zero S communicates in two ways. Non-critical events pop up as system notifications along the bottom of the dash for about five seconds — messages like 'Power Pack is Too Cold to Charge', 'EVSE not compatible', 'Motorcycle Tipped Over. Key-cycle to reactivate Throttle', 'Motorcycle in Limp Mode' or 'Scheduled Charging'. These are informational and aren't stored. More serious problems generate a numbered error code, which briefly appears and then leaves a code icon on the dash as a reminder.

You can review stored codes yourself: from the Menu, go to Data, then Errors, where up to five recent codes are held (newest first). Highlight a code to read it and use Clear to dismiss it. Codes flagged in the Check Engine Light column force the bike into permanent torque reduction and mean a dealer visit. Many codes, though, are self-recoverable — several battery-module and charger faults simply ask you to disconnect the charger, key off for two minutes and try again, and low-charge codes just tell you to plug in.

Behind all of this the BMS enforces safety interlocks. A Throttle Disable stops you riding when the pack is empty or a serious internal fault is detected, and a Charger-Disable interlock terminates charging when conditions are unsafe. Neither is something you override — they exist to protect the pack and rider.

The Zero S carries a genuinely dangerous high-voltage system. Its high-voltage cables are sheathed in orange for identification; never probe, cut, modify, touch or attempt to service them, and never open the power pack — only Zero-trained technicians are qualified. If the bike is in an accident, stay clear of any orange wiring and connectors. In the event of a fire, knock down visible flame with a Class D dry-powder extinguisher, then douse with water. The 12-volt battery is also off-limits for direct accessory wiring — use only the two dedicated 12V accessory connectors (fed by the DC-DC converter), because wiring accessories straight to the battery can disrupt operation and ABS.

Two automatic safeguards protect low-speed handling. A tip-over sensor disables drive mode if the bike falls; you re-enable the throttle with a key cycle. Dropping the kickstand also disables the drive and lights a dash indicator, so the bike can't lurch away while parked. Always park with the key OFF and removed to deter theft.

As the owner you're responsible for the legal and mechanical basics: ride within your licence category (the A1 variant exists specifically to meet restricted-licence limits), obey local laws, and always wear an approved helmet and protective gear. The S is designed for a rider plus one passenger only, within the 231 kg (508 lb) combined carrying capacity, and load should be secured low and centred. Keep the firmware current, use only Zero-approved parts and accessories, and replace the 12V battery only with a genuine Zero unit — it includes a cold-weather heater a generic battery won't have.