Yamaha MT125 MT150 owners bible

Which bike models does this Bible cover?

This technical guide is specifically designed for the Yamaha MT-125 and MT-15 (MT-150) platforms. It covers all major generations, including the earlier models and the newer VVA (Variable Valve Actuation) engine versions.

Is this an official Yamaha service manual?

No. This is an independent Technical Bible created for owners. While official manuals can be dense and hard to navigate, this guide is streamlined to focus on the most common repairs, maintenance tasks, and technical specs that owners actually need in the garage.

What kind of technical data is included?

You get instant access to:

• Torque Settings: Every critical bolt from the axles to the cylinder head.

• Fluid Capacities: Exact measurements for oil, coolant, and fork fluid.

• Maintenance Schedules: Know exactly when to check your valves or change your chain.

• Real world owners: incites on common issues and fault from owners.

Can I access the guide on my phone?

Yes. The Bible is fully optimized for mobile devices. It’s designed to be used as a digital companion while you are working on your bike, with large text and clear diagrams that are easy to read on a small screen.

How do I receive the guide after purchase?

Immediately after your payment is confirmed, you will receive a secure link to access the full Technical Library. You can bookmark this link for lifetime access across all your devices.

Do I need professional tools to use this guide?

While we recommend basic quality tools (sockets, torque wrench, etc.), the guide is written for both beginners and experienced home mechanics. We break down complex tasks into manageable, step-by-step instructions.

Engine & Performance Specs

• Engine Type: 124.7cc / 155cc, Liquid-cooled, 4-stroke, SOHC, 4-valve (VVA equipped on 2019+ models).

• Bore x Stroke: * 125cc: 52.0 mm x 58.6 mm

  • 155cc: 58.0 mm x 58.7 mm

• Compression Ratio: 11.2:1 (125cc) / 11.6:1 (155cc).

• Maximum Power: * 125cc: 11.0 kW (15.0 PS) @ 9,000 rpm.

  • 155cc: 13.7 kW (18.6 PS) @ 10,000 rpm.

• Fuel System: Electronic Fuel Injection (EFI).

Fluids & Capacities

• Engine Oil (Change only): 0.95 Litres.

• Engine Oil (With filter removal): 1.00 Litre.

• Recommended Oil Grade: SAE 10W-40 (API service SG type or higher, JASO standard MA).

• Coolant Capacity: 0.48 Litres (Radiator + Engine).

• Fuel Tank Capacity: 10 Litres (including reserve).

• Fork Oil (per leg): 225cc - 230cc (Check specific year for level height).

Critical Torque Settings

• Engine Oil Drain Bolt: 20 Nm (14 lb-ft).

• Oil Filter Cover Bolts: 10 Nm (7.2 lb-ft).

• Rear Axle Nut: 90 Nm (65 lb-ft).

• Front Axle Bolt: 60 Nm (43 lb-ft).

• Spark Plug: 13 Nm (9.4 lb-ft).

• Front Brake Caliper Bolts: 35 Nm (25 lb-ft).

Chassis & Electrical

• Tire Pressure (Front): 29 psi (2.00 bar).

• Tire Pressure (Rear): 33 psi (2.25 bar).

• Drive Chain Slack: 25.0–35.0 mm.

• Spark Plug Type: NGK / CPR8EA-9 or CPR9EA-9.

• Battery Type: 12V, 3.0 Ah (ETZ4V / YZ4V).