Description
Rofun 1/5 Scale Baja Aluminum Case Differential Assembly
5TRC offers the Rofun 85032 complete aluminum-case differential assembly for compatible 1/5-scale Baja vehicles. It features an alloy case, sealed ball bearings and steel out-drives, and is supplied filled with oil. Use it to replace a worn differential assembly. Confirm your vehicle version and differential dimensions before ordering.
Product Details
| 5TRC Item Number | 85032 |
| Inventory SKU | 5TRC85032 |
| Manufacturer MPN | 85032 |
| Product | Complete aluminum-case differential assembly |
| Scale | 1/5 |
| Case Material | Aluminum alloy |
| Included Components | Differential assembly with sealed ball bearings and steel out-drives |
| Oil | Supplied filled with oil |
Differential Assembly Overview
This complete assembly is intended as a replacement for a worn differential. It has an aluminum alloy case, sealed ball bearings and steel out-drives, and arrives filled with oil. Check the supplied product images and compare your existing assembly before installation.
Fitment and Installation Notes
Listed for compatible 1/5-scale Rovan and King Motor Baja vehicles and HPI Baja 5B/5T applications. Fitment can vary with model generation and driveline configuration. Verify your vehicle version and compare dimensions before ordering, particularly for HPI applications. Follow the vehicle manual or consult an experienced RC technician for differential installation.
Disclaimer and Safety Notice
All items offered by 5TRC are brand new. 99.9% of our customers experience no issues with the products. If you are new to the hobby, we strongly encourage you to watch our instructional videos available through YouTube. 5TRC sells Genuine Rofun products through 5TRC.com and eBay without an express or implied warranty. Enthusiasts commonly customize and modify these vehicles, so 5TRC sells these products without guarantees of any kind. For purchases made through eBay, eBay Money Back Guarantee coverage may apply.
Gasoline RC engines and exhaust components become extremely hot and can cause severe burns. Improper operation can cause serious injury through impact with the operator, bystanders or pets. Operate responsibly, keep bystanders and pets away, and inspect the vehicle before every use. By purchasing this product, you agree to hold harmless 5TRC from liability for accidents, injuries or damages resulting from its use or misuse.
Maintenance and Setup
Large-scale gasoline RC cars require regular adjustment, maintenance and mechanical work. New vehicles may need minor adjustments to the servo horn, carburetor, camber and other components. Inspect the vehicle before the first run and apply thread-locking compound only to appropriate metal-to-metal fasteners. RC tool kits and setup tools can help with routine maintenance and adjustments.
Follow the engine manufacturer’s service and adjustment instructions. Stop and correct unsafe lean running, uncontrolled idle or a mechanical problem before continuing.
Rofun Car and Truck General Assembly and Operation
Before operation: Install and secure vehicle components according to their instructions. Check steering, throttle, brakes, fuel lines, fasteners and radio operation before each run.
Battery charging: Use a charger suitable for the battery chemistry, voltage and connector. Follow its charge-completion indicator and disconnect when charging is complete. Do not charge unattended. Allow a warm battery to cool before use and follow the battery instructions for storage. We use a countdown timer. A countdown timer does not replace charger supervision or automatic charge termination.
After a crash: Inspect the vehicle, steering, brakes, fuel system and radio operation before continuing.
Fuel Mixing
Use a 25:1 gasoline-to-oil ratio, equal to 5.12 US fluid ounces (151.4 ml) of oil per US gallon of gasoline. If using a mixing jug with 25:1 markings, fill the small compartment to the 25:1 line with oil, then fill the gas compartment to the 25:1 line. You may also find a 2 stroke oil measuring cup handy. Use non-synthetic, mineral-based two-cycle oil that meets the engine manufacturer’s specification. Follow the engine manufacturer’s specified fuel and oil ratio if it differs.
Oil product information: Evinrude Johnson TC-W3 mineral oil and Evinrude Johnson XD30 oil. Follow your engine manufacturer’s oil specifications when selecting a product.
Radio and Starting Instructions
Radio: Channel count, controls and adjustment locations vary by transmitter. Use the manual for the radio installed in your vehicle to set steering trim, throttle and brake trim, travel limits and failsafe.
Starting: Turn on the transmitter and vehicle, then confirm that both respond correctly. Follow the installed engine and carburetor instructions to prime and start the engine.
When using a pull starter, let the rope engage gently before pulling. Use short, quick pulls and do not pull the rope to its full extension. Follow the engine manufacturer’s instructions for choke use.
Break-In Process
Follow the break-in procedure supplied for the engine. As a general 5TRC guideline for a new or rebuilt gasoline engine, begin with low throttle and short running periods, allowing the engine to cool completely between early runs. Increase engine load gradually and avoid prolonged full-throttle operation during break-in.
Keep debris away from the cooling fins and check for loose fasteners, fuel leaks and exhaust leaks between runs. Make carburetor adjustments only after the engine has warmed up, and correct signs of lean running immediately.
Failsafe and Servo Protection
Set and test the receiver failsafe before operating the vehicle. A braking failsafe can hold the throttle/brake servo under load when the transmitter signal is lost. Do not leave the vehicle powered on with the transmitter off. Continuous servo load can cause overheating or damage. Turn on the transmitter before the vehicle, and turn off the vehicle before the transmitter.
5TRC Rofun 29-45cc Engine Temperature Guidelines
Check a Rofun air-cooled 2-stroke gasoline engine at the cylinder head near the spark plug. Use a Digital Infrared Thermometer to monitor temperature.
Normal operating temperature: 5TRC uses a reference operating range of 230 degrees F to 280 degrees F (110 degrees C to 138 degrees C). Normal driving can produce temperatures from 250 degrees F to 280 degrees F. Allow about 3 to 5 minutes of actual driving for warm-up before making final carburetor adjustments.
Temperature alarm: If your vehicle has temperature telemetry, set a high-temperature warning at 300 degrees F (149 degrees C). This setting provides an early warning when the engine begins running hotter than normal.
High Temperature and Lean Running
Maximum recommended temperature: At about 300 degrees F, reduce throttle immediately. Stop the vehicle if the temperature does not quickly decrease. Continued operation above this level can damage the piston, cylinder or rings.
Running lean: An excessively lean carburetor setting can raise engine temperature rapidly. Other warning signs include unusually high RPM, hesitation, loss of power under load, rising temperature, or RPM that stays high after releasing the throttle. Do not rely only on a temperature sensor because the piston can overheat before the cylinder-head sensor shows the full increase.
After a hard run: After extended high-speed or heavy-load operation, let the engine idle for about 30 seconds before shutting it off.
5TRC recommended settings: Reference operating range: 230 degrees F to 280 degrees F. Temperature alarm: 300 degrees F. Stop and inspect if temperature remains at or above the 300 degree F warning, or if lean-running symptoms appear. Normal warm-up time: 3 to 5 minutes of driving.
Ownership and Compatibility
These are Genuine Rofun Hobby and Racing Grade RC products, not full-size turnkey automobiles. Owners should expect routine maintenance, adjustments and occasional repairs. New large-scale RC owners should seek help from an experienced hobbyist, hobby shop, friend, club or social-media group when needed.
We do not accept returns because a buyer is uncomfortable performing normal adjustments or maintenance. If you are not mechanically inclined and do not have someone available to help, learn what large-scale RC ownership involves before buying.
Compatibility Notice: References to other brands or models indicate possible compatibility only and do not guarantee fitment. Parts from different manufacturers are not necessarily interchangeable, even when made for the same vehicle. Verify all measurements, specifications and compatibility before ordering or installation. We cannot accept returns after installation, modification, bending, stretching, drilling, damage or test-fitting to incompatible parts.
Painting the Clear Body
Paint the inside of the body using Tamiya polycarbonate PS paint for proper adhesion and durability.
For a deeper metalflake appearance, apply a very light coat of clear and then sprinkle a glitter additive, metalflake, or pearl while the paint remains wet. Back it with your preferred colors for a stronger finish.
Practice the painting process first on a scrap piece of plexiglass. Many local lumberyards can provide small leftover or damaged pieces for paint testing.
Product Pictures
Product images may not accurately represent the exact color or appearance of the item received. We provide them to illustrate product features. Some listings may display other items or vehicles for reference; the listing does not include those reference items unless stated. Although we do our best to make every listing accurate, AI-assisted listing work can occasionally introduce inaccurate details or specifications. Please contact us with questions, comments or inaccuracies you notice.
Some of our items may include links to products on Amazon. As an Amazon Associate, I earn from qualifying purchases.
Questions? Text-to-eMail: 937-627-0005 Phone 937-205-6312
5TRC, USA’s #1 Rofun Distributor.
