Cylinder & Piston Specifications For Your 2009 – 2010 Honda CRF450R Dirt Bike
If you need parts and tools make sure to buy them here!
Part | Standard (mm) | Service Limit (mm) |
Cylinder | ||
| – I.D. | 96.000 – 96.015 | 96.025 |
| – Out-of-Round | – | 0.010 |
| – Taper | – | 0.010 |
| – Warpage | – | 0.05 |
Piston, Piston Ring | ||
| – Piston Mark Direction | “IN” mark facing toward the intake side | – |
| – Piston O.D. | 95.970 – 95.980 | 95.940 |
| – Piston O.D. Measurement Point | 7.0 (0.30) from bottom of skirt) | – |
| – Piston Pin Bore I.D. | 19.002 – 19.008 | 19.03 |
| – Piston Pin O.D. | 18.994 – 19.000 | 18.99 |
| – Piston-to-Piston Pin Clearance | 0.002 – 0.014 | 0.04 |
| – Top ring Mark | “R” mark side facing up | – |
| Piston Ring-to-Ring Groove Clearance | ||
| – Top | 0.065 – 0.100 | 0.12 |
| Piston Ring End Gap | ||
| – Top Ring | 0.25 – 0.31 | 0.32 |
| – Oil Ring (Side Rail) | 0.20 – 0.70 | 0.71 |
| Cylinder-to-Piston Clearance | 0.020 – 0.045 | 0.085 |
| Connecting Rod Small End I.D. | 19.016 – 19.038 | 19.05 |
| Connecting Rod-to-Piston Pin Clearance | 0.016 – 0.044 | 0.06 |
Keep Your ’09-’10 CRF450r Running Right!
- Service Specification
- Clutch Replacement
- Fuel System Service
- Engine Top End
- Brakes
- Exhaust
- Front Suspension & Steering
- Rear Suspension
- Wheels & Tires
- Kickstarter
- External Shift Linkage
