QUADIFYRC RC Car Review and Upgrade Guides

The HBX 901a 1/12 brushless truck as reviewed here is a brushless 1/12 scale desert buggy and one of my favourite RC cars of 2021. It was light yet very durable with a very efficient power system and drive train. Short gearing ensured very lengthy battery life and ensured motor and ESC temps remained extremely low with the preference of strong acceleration over top speed. In this article I'll show you how to install a larger 14t pinion gear and talk about the performance improvements.

In my original review I mentioned that the motor mount for this car had preset motor holes that should allow the fitment of a 14t pinion and recommended the Surpass Hobby M0.6 13-17t pack. I can now confirm that these do fit as expected - see the images and steps below to do this yourself - it is very easy and takes around 5-10 minutes.

Click on any image to embiggen

Improvements
When I reviewed this car with the stock 12t pinion gear I managed a top speed of 39km/h. Not super quick but the strong acceleration and outstanding battery life more than made up for it although it did feel a little slow in large open areas. With the larger 14t pinion gear as installed above I was able to increase the top speed to 45 km/h which certainly feels a little faster, especially in big open spaces. I can't really feel that I've lost anything in acceleration which suggest to me that at least with my driving that it was probably a bit under geared before.

Downsides
​Going up in pinion size does bring a few downsides as expected: Battery life is down from around 20 minutes to maybe around 17 minutes. Additionally the car has gone from having a barely lukewarm motor and ESC at the end of a battery to having a warm motor and kinda hot ESC however this was in really tough conditions - 26 degrees C ambient temp today and thrashing it full throttle on loose gravel and on grass; something of a torture test. Below is my initial reaction when I finished the first pack on this car:

In short yes, I definitely recommend this mod. The downsides I mentioned above are not really that bad because the gearing was originally so conservative meaning it had massive battery life and the coolest motor and ESC I've ever felt. This means giving a little of this away is barely an inconvenience. On the plus side no one really ever says no to wanting a little more speed, especially when the acceleration is not really compromised. The beauty is that if it is not for you then you can easily revert back to stock and you have more knowledge about your car for very little money spend. All in all a mod for the already excellent HBX 901a brushless 1/12 truck that I heartily recommend.

The 1/14 and 1/12 scale WL toys cars (144001, 124018, 124019) are rightly very popular cars due to their competitive price for a platform that is extremely versatile and lends itself well to upgrade - I have over 30 articles here that prove it. Although on road wheel options are easily accessible, this is less the case with off road options other than the Remo P6973 (reviewed here) which have been the gold standard. I've now found a wheel and tyre set I find to be even better offroad so long as specific conditions are met: ​4PCS Upgraded Larger Tires Wheels 12mm Hex for Wltoys 144001 124018 124019 RC Car Vehicles Model Parts - 1822G-A. Read on to find more about their good, and bad points to see if they are right for you.

Wheel Style. These new wheels/tyres which I will refer to from here as the 1822 have options for either solid disc or spoked wheels in black, white and neon green. They come in a set of 4 with a set of foam inners and of course the tyres. Tyres come in one of two pattern styles, one I would call a paddle  style and the other a knobbly style.

The common platform shared by the WL Toys 144001, 144010, 124016, 124017, 124018 and 124019 is a generally robust one but it does tend to have a common weak point - the front hub carrier AKA front wheel seat. I'm happy to say I've found a cheap, strong and well-made metal alternative and in this article I'll show you why they are only now worth getting and of course how to fit them

When you have been lurking around in Facebook groups, RC Groups, Reddit and other forums dedicated to the WL toys cars as long as I have you tend to pick up on common threads, especially when users share their disappointment over broken parts. Sure, individuals drive in different ways which can put certain components at more or less risk but a very common breakage I see is of the plastic front hub carriers. Standard replacement are not expensive but often have to come from China meaning you can be without a running car for up to several weeks. Previously I've looked a metal replacement parts by WL Toys however early designs were more "agricultural" in style and meant the wheels like my favourite Remo P6973 (reviewed here) couldn't be fitted.

The WL Toys 104001 is a well designed 1/10 scale 4wd off road RC buggy that I reviewed here It is somewhat lacking in power and is only able to achieve a fairly modest 39km/h which feels slow for a car this size. This is due to the stock brushed motor - this is old but cheap technology which in general are slow and inefficient; they just don't do justice to the otherwise good handling car. Brushless motors and ESCs offer improvements across the board - more speed, better battery life through more efficiency and cooler running. In this upgrade guide I'll show you how to get A LOT more power and battery life on the cheap with a budget ESC and motor combo and give you exact feedback on exactly how it performs including speed runs

Recently I looked at a more expensive brushless upgrade for the WL toys 104001 in my Big Brushless Upgrade and Installation Guide. This offered a big increase in performance (76km/h top speed) and battery life but was a pretty expensive option owing to the high end Hobbywing Max 10 SCT speed controller I used with a 4s battery. This time around I've put together a cheaper and easily accessible build that is perhaps better suited to this car and is still about 90% as good as the much more expensive option, depending of course on your metrics.

I've now built up quite a library of articles for the WL Toys 144001 (and 124019 / 124018) and thought I would use this page to share them. As of 3 August 2021 I've finally done a bit of an overhaul to make sure all articles are included and have added some new categories plus reviews. Enjoy!

The WL toys 124016 and 124017 are faster and more efficient brushless version of the hugely popular 124018 and 124019. If you want to know more about these new brushless cars then check out the preview article I wrote here: ​WL TOYS 124016 124017 PREVIEW: FIRST FACTORY BRUSHLESS WL TOYS RC CARS
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In this  article I'll be taking you through my top 5 mods for this car

If the stock car is anything to go by, the brushless model will be at least as fast but with much stronger acceleration and better battery life. With the understanding that you will be going faster for longer, there is an increased change of breakages on what is not an especially weak but not an especially strong car either. In addition, the extra speed and acceleration will show up the handling. For these reasons and but one of the 5 best mods below to improve your 124016 or 124017 will focus on DURABILITY and HANDLING and maybe just a little more POWER

The WL Toys 104001 is an all new 1/10 scale 4WD offroad RC Buggy that was released in 2021 and you can find my full review of the 104001 here. I found this to be a great handling car but felt a little on the slow side. I was able to get some more speed out of it for very little money by increasing the size of the pinion gear here but performance is still a little on the lack-lustre side. Clearly this car is crying out for a brushless upgrade so it's my pleasure to present the one I have put together and have been testing over the last few months and I'll call the 104001 big brushless upgrade. 

The WL Toys 124019 is a small and fast car out of the box - it'll do 55km/h on the old technology brushed motor that comes stock out of the box. For bashing and off-road I prefer to upgrade with physically smaller and more efficient brushless motors but if straight-line on road speed is your objective as is the case here, then using a 3650 sized motor can get you massive speed... there are many examples where this car can go well over 100mph. The objective of my build here is to see what kind of speed I can get without pushing the budget or modifications too far - bolt in parts, stock body and a car than is as reliable as stock and can easily be converted back.

For this build I've chosen the WL Toys 124019 which is a long-wheelbase version of the popular 144001. The reasons this car makes for a good speed run build is:

1. It's cheap - around $100-$120
2. It has a fairly strong and efficient 4wd drive line
3. The comparatively massive brushed motor can easily be replaced with a comparatively massive brushless motor
4. The long wheelbase allows for more room for large components (namely ESC and motor)
5. The car is relatively durable with low cost replacement parts

Let's get on to the build which I have broken down into sections. We'll start with the powertrain which most of you are here for but I'll also cover important lessons in wheel/tyre choice, suspension set up, aero, speed measurement and driving technique. Read on for more

Now that I've finished my review of the new WL Toys 104001 4wd 1/10 scale RC buggy it's clear that this is nowhere near as fast as the earlier 124018/124019 and 144001 models which uses essentially the same electronics. In this article I look at how easier it is to close this speed gap and the theory around it.

My recent guide on upgrading the 144001, 124018 and 124019 with a drop in 2445 5400kv made for a very fast car but also generated a lot of heat for the motor and ESC. In this guide I have a brief look on the impact of adjusting ESC timing on power output as measured by speed and the resulting change in heat of motor and ESC plus efficiency.

Most cheap ESCs, notably the Surpass/Racerstar are impressive in that there is some basic ability to programme the ESC for throttle punch, dead band, low voltage cut off plus braking and reverse as you can see in this guide. Step up to a more premium ESC like the hobbywing 16BL30 and 10BL120 as recommended in my brushless guide and amongst other items you also have the ability to adjust motor timing.