Engine Fluids, Gear Oil & Filter Specifications
| Engine Oil Viscosity & JASO/API Standard | SAE 10W-40 | API SG/SL | JASO MB |
|---|---|
| Engine Oil Drain & Refill Capacity | 1.4 L (Without Filter Change) / 1.5 L (With Paper Filter Change) |
| Final Drive / Gearbox Oil Viscosity & Capacity | SAE 10W-40 or SAE 80W-90 | 250 ml (Drain) / 270 ml (Total) |
| OEM Oil Filter Part Number | Paper Filter OEM # 5HM-13440-00 |
| OEM Air Filter Element Part Number | OEM # 1B7-E4451-00 |
| Spark Plug Model & Electrode Gap | NGK CPR7EA-9 (0.8 – 0.9 mm gap) |
Field note: The low-slung Morphous 250 engine uses a dedicated paper filter element (OEM # 5HM-13440-00). Always replace the filter cover O-ring during oil changes to prevent oil leaks on the long crankcase housing. Cross-reference the Yamaha XMAX 300 guide and Yamaha Majesty 400 guide for mid-to-large maxiscooter fluid maintenance protocols.
CVT Transmission System
| Component | CVT Drive Belt |
|---|---|
| OEM Part Number | 1B7-17641-00 |
| Dimensions | Kevlar reinforced |
| Torque Spec | Primary sheave nut: 60 Nm |
| Cross-Compatibility | Yamaha Maxam 250 |
Field note: Always clean the crankshaft taper to bare metal before torquing to 60 Nm — a taper joint torqued over even light surface corrosion reads "tight" on the wrench while actually delivering less real clamping force, allowing the nut to loosen prematurely and produce a knocking noise under acceleration that gets misdiagnosed as a bad belt or worn rollers.
Engine Internals: Cylinder Head & Crankshaft
| Part No. | Qty | Part Name | Notes |
|---|---|---|---|
| 1B7-11181-00 | 1 | Head Comp., Cylinder | Resurface flatness tolerance 0.05mm max |
| 1B7-12111-00 | 1 | Valve, Exhaust | Check margin thickness > 0.5mm before reuse |
| 1B7-12101-00 | 1 | Valve, Inlet | Do not swap positions with exhaust valve |
| 1B7-11351-00 | 1 | Gasket, Cylinder Head | Single-use metal composite; never reuse |
| 1B7-11421-00 | 1 | Camshaft Comp. | Chain-driven; inspect lobe wear before reinstall |
| Part No. | Qty | Part Name | Notes |
|---|---|---|---|
| 1B7-11400-00 | 1 | Crankshaft Comp. | Check runout < 0.03mm on V-blocks |
| 1B7-11650-00 | 1 | Connecting Rod | Big-end side clearance spec: 0.1-0.4mm |
| 1B7-11631-00 | 1 | Piston (Std.) | Domed piston, 3-ring set |
| 1B7-11633-00 | 1 | Piston Pin | Lightly oil before install; hand-pressure fit only |
| 1B7-11635-00 | 2 | Piston Pin Clip (Circlip) | Directional installation — see expert note below |
Field note: On this 250cc single shared with the Yamaha Maxam 250, the piston pin circlips must be
installed with the opening gap oriented 90° to piston travel, never fore-or-aft. A backward clip
compresses under load until it ejects into the crankcase, and the freed pin gouges the cylinder wall on
the next stroke, destroying the bore. Use only new clips and confirm full seating by feel.
OEM Body Panels & Color Matching
| Part Name | Team Yamaha Blue | Absolute Black | Pearl White |
|---|---|---|---|
| Front Cowl | Consult Service Manual | Consult Service Manual | Consult Service Manual |
| LH Side Panel | Consult Service Manual | Consult Service Manual | Consult Service Manual |
| RH Side Panel | Consult Service Manual | Consult Service Manual | Consult Service Manual |
| Windscreen | Consult Service Manual | Consult Service Manual | Consult Service Manual |
| Rear Trunk Cover | Consult Service Manual | Consult Service Manual | Consult Service Manual |
Field note: Given this platform's age, assume the plastic mounting tabs behind the painted surface are
already past the typical three-year UV brittleness threshold. Never use an impact driver on body screws,
and apply silicone grease to rubber grommets before removal — color-matched replacement panels are
frequently discontinued for this model.
Official Technical Reference
The specifications above are cross-checked wherever possible, but this guide does not replace the factory service manual. Before ordering parts or performing a repair, confirm current fitment and revision bulletins directly with Yamaha Motor USA.
Visit Yamaha Motor USA Official Site & Parts Resources