Samix Aluminum Servo Horn for Traxxas TRX-4 (Grey) (25T)
About this part
The Samix Traxxas TRX-4 Aluminum Servo Horn is a double clamp lock style horn developed specifically for TRX-4 trucks. Precision machined to exacting specifications, this horn matches the TRX-4 geometry perfectly and is a great upgrade. The arm features a unique shape and dual clamp design that will keep the horn locked securely to the servo output. Package includes one 25 tooth servo horn and clamp lock hardware.
Features:
- Machined from high quality aluminum
- Clamping head for secure mounting in high stress applications
- Clamp hardware included
- Available in multiple color options with laser etched samix logo
- Available in 23T and 25T servo applications
Reviews4.0 · 3 reviews
This servo horn is claimed to be specifically developed for TRX-4 so I just went for it, because original horn flex to much with aftermarket 20kg servo. It has some minor design flaws. This horn is flat and too thick, while original horn is not(it has steps). It moves steering link rod end down 3mm and it changes suspension geometry. For wheels to be straight, horn must be turn to the side and steering angle on that side is limited a bit then. Also screw that is holding steering link rod end to horn itself is binding with drag link under full compression. Horn itself touches panhard rod slightly under full compression. My friend shaved it on CNC for me. Original horn is 6mm thick. I made it 5mm thick where it is attached to servo shaft to clear a panhard rod. And 3mm thick where rod end is to clear drag link and move rod end into position where it is meant to be. I suppose you can do the modification yourself even with dremel if you want. I have a picture of modified horn : https://www.rcportal.sk/public/upload/1527615587-4643.jpg But other than that, as I said you can live with this horn as it is. You truck axle will not be under full compression while driving very often and most people will not notice slightly limited steering angle on one side at all. But it is shame they do not address this issues under development, especially when it was design for trx-4 exclusively.
I needed a servo horn after my stock horn on my new TRX4 Defender stripped prematurely,I looked some up here on Hobby town website and seen this horn as a second option to the traxxas steal torn. I was kind of backing down from purchasing it due to the previous two reviews saying that they were hitting the mount and had to be modified I went to my local Hobby Town here in Corona CA took a look at it and pulled the trigger I'm glad I did it seems like the manufacturer corrected the issues because the horn bolts are flush with the horn and does not hit the mount whatsoever it turns perfectly as the factory one!
Servo installed and worked great on TRX4. Nice duel locking screws. As other reviewer stated it does rub the panhard bar under full compression however it is very slight and the stock horn also rubs. Had to set left endpoint to 98% so horn will not hit frame at full turn. Overall a great product.
Three reviewers report on this aluminum servo horn for the TRX-4. Reviewers agree it fits and holds up better than the stock horn under a strong aftermarket servo. The main recurring issue is clearance: one owner reports the horn is thicker and flatter than stock, shifts the steering link position, and limits steering angle until modified, and the same owner reports binding and contact with the panhard rod under full compression. A second owner says the horn bolts sit flush and clear the mount with no modification needed, suggesting a later revision may address the earlier fit problems. A third owner reports slight panhard rub that also occurs with the stock horn, fixed by adjusting the endpoint. Which production version each reviewer received is not stated.
- + Stronger than stock horn with aftermarket servo
- + Bolts sit flush and clear the mount
- + Dual locking screws
- + Fits TRX-4 and works well with steering
- − Thicker and flatter than stock, changes steering link position
- − Limits steering angle until adjusted
- − Rubs panhard rod under full compression
- − Link screw can bind under full compression