How to Stop RC Pinion Gears Coming Loose | RSRC
Tired of your motor pinion gear coming loose in the middle of a race? 😤
I saw it happen again this weekend at the French 1/8 Electric Off-Road Championship: drivers losing their motor pinion because of a simple loose grub screw! 😱
It's such a shame to ruin a qualifying heat or a race because of a problem that's so easy to prevent.
Whether you're racing a 1/10 or 1/8 scale electric RC car, here's my method for keeping your motor pinion gear securely in place! 🏁
🛠️ Step 1: Thoroughly Clean the Motor Pinion
The first step is essential: remove all traces of grease, oil, and residue that could prevent the threadlocker from bonding properly.
✅ Use a brake cleaner spray to thoroughly clean the motor pinion gear, paying particular attention to the threaded hole that holds the grub screw.
💡 My tip: let the cleaner evaporate completely before moving on to the next step. The threads must be perfectly clean and dry.
🔩 Step 2: Degrease the set Screw
This step is often overlooked, but it's absolutely essential!
- Soak a clean microfiber cloth with brake cleaner.
- Carefully rub the pinion grub screw with the cloth.
- Pay special attention to the threads to remove any remaining oil, grease, or old threadlocker.
- Allow it to dry completely.
🎯 The goal: perfectly degreased threads to ensure maximum threadlocker effectiveness.
🔵 Step 3: Apply Blue Thread-locker (Medium Strength)
Once the screw is perfectly clean and dry, apply a small drop of medium-strength blue threadlocker directly to the threads, then spread it evenly over the threads using a suitable applicator.
✅ Blue threadlocker helps secure the screw against the strong vibrations generated by brushless motors while still allowing removal with the appropriate tool.
⚠️ Warning: don't use too much! A small amount is enough. Excess threadlocker could bond the pinion to the motor shaft and make future removal difficult!
💪 Step 4: Firmly Tighten the Pinion Set Screw
Reinstall the pinion on the motor shaft, making sure it is properly aligned with the spur gear.
Make sure the grub screw sits against the flat section of the motor shaft, if one is present.
🔧 Use a high-quality hex driver and firmly tighten the screw without damaging the hex socket or threads.
🏁 Your pinion gear is now securely installed!
Allow the threadlocker to cure for the time recommended by the manufacturer before driving. Also remember that threadlocker is an adhesive with an expiration date!
🔁 Step 5: Repeat the Process Every Time You Remove It!
This is THE rule to follow if you want to stop losing your motor pinion gear! 🔥
Every time you remove or loosen the pinion grub screw, you must repeat the entire process:
- 🧼 Clean the pinion gear with brake cleaner spray.
- 🧽 Degrease the grub screw using a microfiber cloth soaked in brake cleaner.
- 🔵 Apply a fresh drop of blue threadlocker.
- 🔩 Firmly tighten with the appropriate hex driver.
- ⏳ Allow the threadlocker to cure before use.
Never reuse a screw with only the remains of old threadlocker and assume it will still be properly secured!
🦈 My Tip: 2 Minutes of Preparation Can Save Your Race!
After all these years spent racing, I can assure you that it's often the small details in preparation that make the biggest difference in competition!
Whether you're racing 1/10 Touring Cars, Buggies, Stadium Trucks, or 1/8 Electric Buggies and Truggies, take the time to properly secure your motor pinion gear.
A thorough cleaning, a drop of blue threadlocker, and proper tightening can save you a lot of trouble!
⚠️ Use brake cleaner in a well-ventilated area with the vehicle powered off, avoiding bearings and sensitive plastic components.
🦈 Find all the maintenance products, threadlockers, and tools for your RC car on our website!
See you at the track! 🏁🔥
Reno Savoya
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