Factory Workshop SpecificationsPlatform Gen: 2016–2024

2021 Triumph Bonneville T120 Specifications & Consumables

Official workshop technical reference: fluid capacities, spark plug codes, drive chain specs, and tire inflation pressures.

Gen 2016–2024

Factory Platform Compatibility: All workshop fluid capacities, maintenance milestones, torque specifications, and consumables on this specification sheet are factory-identical across model years 2016 through 2024.

Select Model Year:(Active: 2021)

2016 2017 2018 2019 2020 2021 2022 2023 2024

Engine

1200cc

Drive

525

Cooling

Liquid-Cooled

Engineering Subsystem Workbenches & Calculators

Dedicated deep-dive diagnostic tools, torque matrices, wiring pinouts, and calculators tailored for 2021 Triumph Bonneville T120.

10 Dedicated Engineering Spoke Pages

Subsystem Guide/torques

Fastener Torques

Engine drain plug, axle spindles, caliper mounts, triple clamp pinch bolts & thread lubrication derating guide.

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Subsystem Guide/fluids

Fluids & Capacities

Oil: 3.80 L (4.02 US qt) • Coolant: 1.52 L (1.61 US qt) • Brake: DOT 4

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Subsystem Guide/fuses-relays

Fuses & Relays

Main: 30A Blade / Starter Solenoid • Location: Under rider seat

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Subsystem Guide/compression

Compression & Leakdown

Ratio: 10.0:1 • Std: 150-195 PSI • Limit: 130 PSI

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Subsystem Guide/valves

Valve Clearances

Intake: N/A mm • Exhaust: N/A mm

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Subsystem Guide/fuel-delivery

Fuel Delivery & TB Sync

Idle: N/A • Rail Pressure: N/A • Vacuum: N/A

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Subsystem Guide/electrical

Charging & Battery

Battery: YTX12-BS (180 CCA) • Regulated: 14.2 - 14.8 V DC (at 5,000 RPM with High Beam)

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Subsystem Guide/tires

Tires & Gearing

Front: 100/90-18 (36 PSI) • Rear: 150/70R17 (42 PSI)

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Subsystem Guide/suspension

Suspension & Sag

Front Travel: 120 mm • Rear Travel: 120 mm

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Subsystem Guide/maintenance

Maintenance Schedule

Oil: Every 10,000 miles (16,000 km) mi • Valves: Every 26,600 mi • Spark Plugs: Every 10,000 miles (16,000 km) mi

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Fluids & Service Capacities

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Engine Oil (Drain & Filter Change)3.80 L (4.02 US qt)

Engine Oil (Drain Only)3.40 L (3.60 US qt)

Recommended Oil Viscosity10W-40 or 10W-50 Semi/Full Synthetic, JASO MA2

Coolant System Capacity1.52 L (1.61 US qt)

Brake Fluid StandardDOT 4

Drivetrain, Chain & Gearing

Shop Chains & Sprockets →

Drive Chain Pitch525

Chain Link CountN/A

Front Sprocket TeethN/A

Rear Sprocket TeethN/A

Final Drive Configuration525 Pitch Chain

Ignition & Electrical Specifications

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OEM Spark Plug Part NumberNGK LMAR8A-9

Electrode Spark Plug Gap0.9 mm (0.035 in)

OEM Battery Reference CodeYTX12-BS

Battery Output & Rating12V 10Ah 180 CCA

Spark Plug Inspection Interval10,000 miles (16,000 km)

Wheels, Tires & Inflation Pressures

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Front Tire Dimensions100/90-18

Cold Front Inflation Pressure32 PSI (Cold)

Rear Tire Dimensions150/70R17

Cold Rear Inflation Pressure36 PSI (Cold)

OEM Wheel Rim Widths (F / R)3.50" / 5.50"

Official NHTSA Safety Recalls & Technical Bulletins

2 Active Campaigns

U.S. Department of Transportation compliance database (Title 49 U.S.C. Chapter 301).

Verify VIN on NHTSA.gov

The U.S. National Highway Traffic Safety Administration reports 2 safety recall campaigns associated with this platform. Independent repair shops and riders should confirm that authorized dealership warranty remedies have been applied.

NHTSA #24V785000ELECTRICAL SYSTEM:WIRING:CONNECTORS/PLUGS/RECEPTACLES

Received: 21/10/2024▼

Defect Description

Triumph Motorcycles America, Ltd. (Triumph) is recalling certain 2022-2024 Bonneville T100, T120, T120 Black, 2022 Triumph Street Scrambler, Street Scrambler Sandstorm, Street Twin, Street Twin Goldline, 2023-2024 Scrambler 900, and Speed Twin 900 motorcycles. The wiring between the alternator and main harness connector may short circuit and overheat.

Safety Hazard / Consequence

Overheated wiring increases the risk of a fire or crash.

Factory Remedy & Repair Action

Dealers will install a new wire alignment clip, free of charge. Owner notification letters were mailed November 18, 2024. Owners may contact Triumph customer service at 1-678-854-2010. Triumph's number for this recall is SRAN 627.

Manufacturer Notes: Owners may also contact the National Highway Traffic Safety Administration Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153) or go to nhtsa.gov.

NHTSA #26V078000ELECTRICAL SYSTEM:ALTERNATOR/GENERATOR/REGULATOR

Received: 11/02/2026▼

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