Description

Yamaha YZ125 Parts Catalog

If you’ve ever ordered a part for a YZ125 from a third-party schematic online and ended up with a bolt that’s a quarter-inch too short, you know the pain. The official Yamaha YZ125 Parts Catalog is what you need. 57 pages of factory microfiche diagrams, with Yamaha’s own part numbers. This is what dealers use. The foreword (page 4) explains how to read the parts list—including assembly quantities and abbreviations like “UR” (use specified part number) and “AP” (alternate parts). No guesswork.

Engine and Crankshaft: What You’ll Find in This Parts Catalog

The Engine section covers Cylinder Head, Governor, Crankshaft.Piston, Water Pump, Radiator.Hose, Intake, Carburetor, Exhaust, Crankcase, Crankcase Cover 1, Starter, Clutch, Transmission, Shift Cam.Fork, and Shift Shaft. Each component is shown in an exploded diagram with the exact Yamaha part number and quantity. Need to replace the crankshaft? The catalog shows you the full assembly, including bearings and seals. No aftermarket cross-reference that might be wrong.

Does This Manual Cover the Carburetor and Fuel System?

Yes. The Carburetor section includes the pilot jet, main nozzle, and float bowl gasket. The Fuel Tank section lists the tank assembly, graphics, cap, and petcock. The Intake section covers the reed valve and intake manifold. If you’re rebuilding the top end, you can verify all the gasket part numbers from the Cylinder Head and Crankcase sections. I’ve seen too many DIY guys order the wrong gasket set because they trusted a generic list.

57 Pages of Factory Diagrams

That’s the whole catalog. Page 57 is the Numerical Index—if you have a part number from a previous order, you can look it up and find the diagram reference. The chassis section covers Frame, Fender, Side Cover, Rear Arm, Rear Suspension, Steering, Front Fork, Seat, Front and Rear Wheels, Brake Calipers, Master Cylinders, and more. There’s even an Alternate (Chassis) section and Optional Parts 1 for accessories. Every Brake component, from the Front Master Cylinder to the Rear Brake Caliper, is listed with its factory part number. Suspension parts (Front Fork, Rear Suspension) are broken down to springs, bushes, and seals.

Get the Right Part Numbers the First Time

Page 5 shows the Model Label location and how to decode the model code and production code. For example, YZ125P (5NY1) for USA and Canada. Before you order, verify your frame number against the list. That step alone saves you from ordering a part meant for a different market. The catalog covers YZ125P and YZ125 models for North America, Europe, Japan, and Australia. Use the correct diagram for your specific sub-model.

Yamaha YZ125 Parts Catalog vs Aftermarket: Why Factory Matters

I’ve seen aftermarket parts catalogs that swap part numbers or miss entire sections like the Governor or the Generator. This is OEM. It includes the Electrical 1 section with the generator and handle switch diagrams. The Transmission section shows the shift cam, fork, and shaft assemblies with the correct circlips and bushings. If you’re assembling a bottom end, you need these diagrams to confirm you have every thrust washer. The Yamaha Parts Catalog is the source. Trust it.

Does this catalog include torque specs?

No, this is a parts catalog, not a service manual. You need a separate service manual for assembly torque values.

How do I read the part number format?

The foreword on page 4 explains that parts supplied in an assembly have a dot (.) before the part name, and the quantity is listed to the right of each component. Use the “Numerical Index” on page 57 to find any part number quickly. The catalog also notes modifications after the first edition with an asterisk (*) before the reference number. Pay attention to those.

Still need a service manual? Check the related manuals below. For a general look at how engines work, see Internal Combustion Engine. And for context on automotive part numbering standards, Automotive Industry Overview has background. But for your YZ125, this is the only parts catalog you should trust.

• Yamaha YZF-R1 2002 Parts Catalog – OEM Factory Part Numbers
• Yamaha GTS1000AE 1993 Parts Catalog – Factory Microfiche PDF
• Yamaha V125 Parts Catalog – OEM Factory Part Numbers & Diagrams

Access the Factory Manual now and stop wasting time on incorrect parts.