Description
Rofun 5B Plastic Servo Saver Cam and Spring Arm Kit
5TRC offers the Rofun 852271 plastic servo saver cam and spring arm kit for compatible 1/5-scale HPI Baja 5B, Rovan and King Motor Baja vehicles.
Product Details
| 5TRC Item Number | 852271 |
| Inventory SKU | 5TRC852271 |
| Manufacturer Part Number | 852271 |
| Product | Plastic servo saver cam and spring arm kit |
| Component Type | Buffer/rocker arm kit |
| Material | Plastic |
| Fitment | Compatible 1/5-scale HPI Baja 5B, Rovan and King Motor Baja vehicles |
| Quantity | One kit; individual component count is not specified |
Servo Saver Kit Overview
This plastic replacement kit is part of the Baja steering servo saver assembly. Match the original buffer/rocker arm parts and steering layout before ordering or installation.
Fitment and Installation Notes
Listed for compatible 1/5-scale HPI Baja 5B, Rovan and King Motor Baja vehicles. Configurations may vary by model. Compare the original part, mounting points and steering arrangement before ordering.
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.
Exhaust components can cause severe burns when handled improperly. Improper operation can also cause serious injury or death through impact with the operator, bystanders or pets. By purchasing this product, you agree to hold harmless 5TRC from liability for accidents, injuries or damages resulting from 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. Many experienced owners inspect the entire vehicle before the first run and apply thread-locking compound to appropriate metal-to-metal fasteners. RC tool kits and setup tools can help with routine maintenance and adjustments.
Use the engine manufacturer’s initial carburetor settings during break-in. Stop and correct unsafe lean running or uncontrolled idle before continuing. Make final performance adjustments after break-in.
Rofun Car and Truck General Assembly and Operation
Out of the box: Install the wheels and charge the car battery before operation. Charge using the instructions for the installed battery and its compatible charger.
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. 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 the included mixing jug, 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 to be handy. Use non-synthetic, mineral-based two-cycle oil. Other brands can also work.
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 radio and car and confirm that both respond correctly.
Move the red choke lever on the carburetor to the vertical closed position.
Press the primer bulb 3 to 4 times, or until you see fuel.
Pull the starter rope gently until it engages, then pull swiftly. Use short, quick pulls and do not pull the rope to its full extension.
Crank until the engine fires, usually within 1 to 3 pulls. Never crank more than 3 times with the choke on.
Turn the choke off, then pull the starter 1 to 2 times to start the engine.
Break-In Process
Initial run: Run the car at idle to 1/4 throttle or less for about 5 minutes, then let the engine cool completely.
Second run: Repeat for 10 minutes, then let the engine cool completely.
Third run: Increase gradually to half throttle. A new engine creates extra heat from friction. Run for 8 to 10 minutes, then let it cool completely.
Subsequent runs: Continue for about five runs. Keep debris away from the cooling system because a clean engine runs cooler.
Final break-in: After the engine completes the required break-in, introduce brief full-throttle runs gradually and avoid prolonged heavy loading. Check for loose bolts and debris between runs.
Post break-in: Check and snug the exhaust pipe after the initial break-in process.
Before each run: Check bolts throughout the car. We recommend threadlocker on appropriate clutch and brake assembly bolts. Clean bolts and holes with alcohol and a cotton swab to improve threadlocker adhesion.
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°F to 280°F (110°C to 138°C). Normal driving can produce temperatures from 250°F to 280°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°F (149°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°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°F to 280°F. Temperature alarm: 300°F. Stop and inspect if temperature remains at or above the 300°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 vehicles, 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.
Test the complete paint combination on a scrap of the same polycarbonate material before painting the body.
Product Pictures
Product images may not accurately represent the exact color of the model purchased. We provide them to illustrate mechanical features. Some listings may display other items or cars 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.
