Moose Clutch Master Cylinder Rebuild Kit
1039-4903 (MFG #: 18-4000)
$38.95
Sale price
$38.95
Regular price
$38.95
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Moose Clutch Master Cylinder Rebuild Kit for BETA RR 390 Dirt Bike
Moose Clutch Master Cylinder Rebuild Kit for BETA RR 390 Dirt Bike
$38.95
Sale price
$38.95
Regular price
$38.95
SKU:1039-4903
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Description
Please Note
- C-clip not included with some models
Features
- Kit contains all of the components to re-seal leaking master cylinders.
- Kit includes: replacement hard anodized aluminum piston, replacement cover screws, boot, and spring.
Technical Specifications
- MFG. Part Number 18-4000
Vehicle Information
BETA RR 390 Dirt Bike (2015-2026)
The BETA RR 390, an acclaimed off-road motorcycle produced from 2015 to 2026, is renowned for its robust performance and versatility. It consistently features a single-cylinder, 4-stroke, liquid-cooled engine paired with a six-speed transmission, delivering smooth power, strong low-end torque, and a lively midrange ideal for enduro riding. Over its production run, the RR 390 has seen significant refinements. While engine displacement remained largely consistent, early models (2015-2017) were initially carbureted, transitioning to electronic fuel injection (EFI) by 2016-2017, which became standard from 2018 onwards. Chassis updates were notable, with a redesigned frame for the Race Edition in 2017, a new chassis across all RR 390 models in 2018, and further enhancements in 2024 for RR Racing models, including a more rigid frame and KYB suspension. Trims include the standard RR, the competition-focused RR Race Edition, the street-legal RR-S (introduced around 2017), and the newer RR X-Pro (2025+) designed for serious trail riding with a lower seat height. These updates ensure the RR 390 remains a top contender in its class. Frequently Asked Questions:
Q: How can I be sure this part fits my specific BETA RR 390?
A: To ensure perfect compatibility, please use the year and edition selector at the top of this page.
Maintenance
| Component | Interval | Details |
| Engine Oil and Filter Change | Every 5 to 15 hours | More frequently (5-7 hours) for aggressive or race-level riding. Less frequently (10-15 hours) for recreational riding, depending on model year. |
| Air Filter Service | Every 5 to 20 hours | More frequently (2-5 hours) in dusty/muddy conditions or for aggressive riding. Less frequently (10-20 hours) for recreational riding, depending on model year. |
| Spark Plug | Regular check | Check color and wear, replace if doubtful. |
| Coolant | Regular check | Check level frequently, especially in hot conditions. Use long-life coolant. |
| Chain (Transmission) | Frequent cleaning and lubrication | Check tension and wear regularly. Replace when teeth are pointed. The timing chain should be checked during major services (90h, 120h, 150h, etc.) and preventively replaced for race use. |
Maintenance intervals can vary based on model year, trim, and riding conditions. It is essential to consult your vehicle's official owner's manual for precise information.