01 August 2019

LEGO® Technic review: 42099 4x4 X-Treme Off-Roader

Posted by Admin
Our final review of summer 2019 LEGO® Technic sets is 42099 4x4 X-Treme Off-Roader which uses the new Control+ system, has 958 pieces and is available as of today for US$249.99/ £199.99/ 229.99€. This time, we welcome back Ryan Welles to reviewing duties! 

It was the year 2007 when the good people in Billund introduced a new motorized system. The Power Functions system, known for its orange banded box art and incorporated in both Creator and Technic sets, is the electrical system that has had the longest lifespan in LEGO® history to date. The powerful motors came in several types and sizes, with infrared remote controls and receivers, and initially showed a combination of studded and studless connections. Later additions to the Technic line included a Large Motor and Servo Motor introduced in 2012, that only allowed for studless mounting. 

Twelve years later, the array of motorized systems used for several LEGO production lines is, to be quite honest, a bit of a mess. Besides Power Functions (which is about to be phased out but will be on the market for a year or two) there is Mindstorms, Boost, Powered Up and SPIKE Prime. The bad news is, with Control+, a sixth line1 has been added to this plethora of motorized systems. The good news: it is an incredible improvement and joy to build and play with, although this sophistication comes with a much higher price level. 

The real wait is for the massive 42100 Liebherr R 9800 with its eight motors, set for an October release, but don't wipe aside the Control+ set you can already get your hands on right now. Set 42099, menacingly called '4x4 X-Treme Off-Roader’, may be be reminiscent of 2012's 9398 4x4 Crawler but is a welcome introduction to the new Control+-system which is just so much fun to operate a mere description cannot possibly suffice. Also, besides the motorized components, the set introduces some new parts and a whole new color for the Technic line. Let's take a closer look! 

New Parts in 42099 4x4 X-Treme Off-Roader

We at New Elementary love new elements (what gave it away?) and this medium-sized Technic set has quite a few useful ones. First of all, there is a two-part universal joint with the ‘Male’ part in Medium Stone Grey/Light Bluish Gray (Element ID 6262968) and ‘Female’ in Dark Stone Grey/ Dark Bluish Gray (Element ID unknown as it is missing in the parts list!) 

There have been several universal joints in the past, allowing axles to operate under an angle. The most well-known ones are the 4-stud long joint used until 2007 (Design ID 9244) and since then the 3-stud long universal joint (61903) that was more useful in odd-length studless building. These elements were quite fragile and had a fixed length, so were joined (no pun intended) later on by a duo of parts: the Steering CV Joint (19991) and Steering CV Joint Axle (92906) which could make the inserted axle slide.

The new universal joint is similar-looking to the aforementioned but joined by a balljoint. 
The maximum angle that can be achieved is about 40 degrees. Remarkably the ball joint used is thicker than the regular balljoints included in other parts. It gives a very robust result. The new balljoint piece has a slit in the ball-part so can only be joined in the 'female 3-stud long part' one way.

It can also be linked to the new wheel hub (Element ID 6275902) introduced in this set.

What makes this new wheel hub so remarkable is the fact it incorporates an internal reduction with a ratio of 1:5.5 by the use of planetary gears. The wait is now on for an AFOL who opens up the wheel hub to see what is inside.

Other new regular parts include the Connector Beam 1x3x3 (39793), aka the Biscuit Frame, and three colors of the new wire clips (Design ID 49283|Element IDs: Bright Blue 6263071,
White 6278194, Bright Red 6263067) we made mention of in April since they are included in the LEGO Education Spike Boost set.

Control+ parts 

The big stars of course are the new motors and receiver unit. It is a pleasant surprise all of these new parts come in their own little black box, giving it an exclusive feeling.

They include:
  • Two XL Motors (Element ID 6214088), which are a little larger than the 'old' Power Functions L Motor with a length of 7 studs and a width and hight of 5 studs. There are no rounded or curved portions anymore, enabling the motor to be built into studless constructions easily (which was always an issue with the Power Functions cylindrical shape). It is here used for driving. It seems to be a a lot stronger than the Power Functions L Motor both in speed and torque.

  • One L Motor (6214085), with dimensions of 7x3x4, that should be comparable with the Power Function L motor, also in size. It has a half-stud height on both top and bottom, making it a bit less 'blocky' than the XL Motor. It also seems to be a tad bit faster than the Power Functions L Motor and is used for steering.

  • The Smart Hub (6142536) which is both a battery box and a received and is 9 studs long, 7 studs wide and 5 studs high. It contains an activation button that makes a white LED light flicker for a short while, four connectivity ports and six sensors (three axis sensors and three accelerometer sensors). Once in operation, the light is blue. By making use of these sensors the hub not only knows the position of the Crawler but also the position of the front wheels, therefore allowing the L Motor to function as a servomotor. 
When I calibrated the motors for the first time I used the app to control it all; this was a big surprise. With these sensors the Control+ app knows the degree of tilting both sideways and from front to back. The hub also houses the six AA batteries that can now be placed in a removable tray, making it a lot easier to load and unload the batteries compared to the Power Functions Battery Box.

All these new components make use of new connectors that are no longer stud/antistud based. A downside is these sophisticated components seem to be quite costly (judging on the price of this set) but most likely these parts will be sold separately in the near future. More bad news is that all these components get stickered in this set, which seems to a rather unnecessary feat.

Parts in new colors and new moulds

It is hard to tell from the official pictures and box art, but this set introduces a new color to LEGO Technic sets (although Technic parts in this color have appeared in BOOST, Bionicle and Hero Factory sets). LEGO calls it 'Flame Yellowish Orange' and on BrickLink it is known as 'Bright Light Orange'. A total number of eleven different parts come in this shade of yellow and rare ones return. You will later see the final result is somewhat treacherous since most of these parts (especially the panels) are almost fully covered with stickers. 

  • Technic Liftarm 1 x 15 Thick: Element ID 6275898|Design ID 64871 (2x)
  • Technic Liftarm 1 x 11.5 Double Bent Thick: 6275882|32009 (2x)
  • Panel Fairing #1 Small Smooth, Side A: 6275900|87080 (1x)
  • Panel Fairing #2 Small Smooth, Side B: 6275901|87086 (1x)
  • Panel Fairing #17 Large Smooth, Side A: 6275895|64392 (1x)
  • Panel Fairing #18 Large Smooth, Side B: 6275896|64682 (1x)
  • Panel Plate 3 x 11 x 1: 6275893|15458 (3x)
  • Panel Plate 5 x 11 x 1: 6275892|64782 (1x)
  • Panel Curved Surface 11x3 with 2 Pinholes through Panel Surface: 6275897|62531 (2x)
  • Panel Plate 5 x 11 x 1 Tapered: 6275894|18945 (2x)
These two pictured have only appeared in one BIONICLE set from 2005:
  • Technic Liftarm 1 x 3 Thick: 6275899|32523 (included 4x)
  • Technic Liftarm 1 x 5 Thick: 6203256|32316 (1x) 
The blue Technic L-shaped Liftarm (32140) is also pictured because I thought it was also new but in fact it is not. What got me confused is LEGO has used a new Element ID.

Something that struck me is the fact that LEGO is replacing the softer ABS, used in parts stemming from the earliest days of studless building, with harder and shinier plastic. I found the very common Cross Block 90° (6536)  is now made of harder plastic, similar to what happened to Double Cross Block (32184) a few years ago. The company seem to be aware of this in all areas, because the part looks different in the instructions. Something similar is happening to the Angle Element (32013) that comes in both the softer and harder type of ABS in this set. Because all of these new molds are Black it is very hard to tell from the pictures. I wonder if this is going to be the plan for all parts made of the softer ABS; it seems likely.

The Build

If you're a fan of gearing you might be in for a bit of a disappointment with this set, since there are few gears included. The build therefore is pretty straightforward, reminiscent of the aforementioned 9398 4x4 Crawler. The sight of so many stickers besides a 224 page instruction booklet may feel off-putting, but I strongly recommend you to apply all of them.

The build is divided into three sections, coinciding with bags numbered 1 to 3. 

You start by building the units containing the wheels. The front unit also takes care of the steering. The new wheel hubs are not only supported by steering arms but also by links on both sides to support the moving steering rack. The result is a condense unit, where only the orange parts look a bit off-set. 

This front unit at first has some unattached red hard-springed shock absorbers that will later on be attached to the chassis. So far, the shock absorber in red only appeared in two sets, so are rather rare. The first XL motor is almost directly linked to the steering unit and its differential. 

At the front end of the unit, a large turntable is attached that will later on will be joined by a second one, providing a large amount of movability of the front wheels. 

The unit containing the rear wheels is very similar to the one just built, except for the steering part of course. It also contains a differential, making the crawler 4x4, and its main color for guidance is blue instead of the blue of the front unit. 

The XL motor is more directly linked to the rear wheel unit. 

Eventually, the two units will be joined by the second large turntable. Additionally, the L motor is placed right in front of its first XL brother and taking care of the steering. The result is a row of three motors. 

At this stage the hub is added. It is placed on some tan axles, making it rather easy to install or remove in order to replace the batteries. The new wire clips are joined with a 3-stud long axle. The colors of the clips correspond to the stickers you put on the motors. I do not really see the use of these clips, to be fairly honest, since the wires despite of the presence of the clips have the tendency to jump all over the place. After the chairs (consisting of grey panels) are added, the chassis is finished. 

The final stage of the build consists of building the coachwork of the crawler. This is a rather straightforward build that requires much of your sticker applying skills. 

The coachwork is attached to the chassis with just a few pins with stop bushes and axles, making it easy to attach and remove. After an hour or two the crawler is finished for its first test drive.

The Control+ App

For this review LEGO was so kind to provide us with a beta version of the Control+ app.

Unfortunately, and as the box indicates, a smartphone is not included. The app works on both Android and iOS systems and it worked like a charm.

After doing a small calibration session the crawler was ready to go!

The functions included are:

  • A two-finger controlling option. You steer with left and drive with right. The maximum speed possible is about 35 km/h.
  • A one-finger option. You need to position the crawler on the screen of your device according to its actual set up and then the app lets you control the crawler simply by dragging your finger across the screen. Such fun!
  • Doing achievements and assignments. This allows you to develop your skills as a driver and impress your friends and family.

Final Verdict

As mentioned earlier, this set does not rely on gearing, which is one of the most prominent features of the LEGO Technic Line. As a result, this set is more suitable for younger builders since there is not much that can go wrong. The main purpose of this 4x4 Crawler is playability and with the new Control+ system a lot of fun is guaranteed. Not only has LEGO introduced a very smooth operating app that through the courtesy of Bluetooth technology has an impressive range, the company has not stuck to simple steering and driving functionality. The play feature is enhanced by the one-touch control option of the app and the challenges and achievements children can compete in. The introduction of sound effects and speed control indicates this new Control+ system is future proof.

You will also find this set has an almost improper amounts of stickers, covering most of the gorgeous Flame Yellowish Orange. I decided to apply all of them, because stickers. The result looks fantastic, yet it remains to be seen what happens to the decals once the crawler is operated and played with outdoors.

The truck itself looks fantastic, with the open space under the hood being the biggest downside. A fake motor, preferably functioning, would have been a welcome addition. Thanks to the use of two big turntable and spring-based suspension the crawler is very versatile and can easily conquer rough terrain and small obstacles. Its biggest let down is the steeping price. It is hard to judge what the production costs of the new Control+ system is (also in developing costs) but for parents wanting to treat their child to something really good, this price may be the quite the hurdle. Seeing it drive is a true joy and I can't wait to put my hands on the upcoming Liebherr that will be the true test of what the new Control+ system is capable of.

1 Some people consider the Control+-motors part of the Powered Up System, with the name Control+ just referring to the app to control it all. I disagree. First of all, the name Powered Up nowhere appears on the box or in the instructions. Second of all, the motors and hub used for Technic are different in looks and functions.

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  1. Geez, that's a bucketload of flimsy stickers, although I'd assume the completed build would look reasonable even without them...

  2. I strongly challenge calling this “Future proof”, if there is no way to control the system without using an App. Apps will become stale and unsupported after a few years. How are you supposed to keep using this system afterwards? Does the PowerUp controller work with this Control+ system?

    1. Take heart - the Lego Powered up team ARE working to improve firmware on all the Smart Hubs - they are WELL aware of futureproofing things like this. There has been some big discussions lately about what Hubs/Motors can achieve on their own, with no App. (eg: Motor + sensor = colour/speed)

      I believe they are not compatible right now, but a future firmware/software upgrade will allow PU App to control this brick, like it can do with the PU Hub, and Move Hub (Boost)

  3. Assuming one of them is not blue ... "and its main color for guidance is blue instead of the blue of the front unit"

  4. Hmmm... wonder if you could use the Spike Prime wheels with some of these Flame Yellowish Orange Technic parts to make a large-scale Legends of Chima "Speedorz" set... :P

  5. Great review, I'm looking forward to getting one of those myself! I have to disagree on a few things, though.

    I'm one of those for which Control+ is not a separate line, but instead belonging to the Powered Up ecosystem. The connectors are the same as for WeDo 2.0, Boost, Trains/Batmobile, and SPIKE; plus, I've seen (but not yet tested myself) a 42099 controlled by a PUp hub and remote control instead of the Control+ hub and phone. With firmware and app updates that I'm certain there will appear in the future, inter-compatibility will significantly increase.

    The sensors in the hub can only detect its orientation; the angle of the motors' axles is sensed in the motors themselves. This should make the motors quite useful with other hubs.

    As a MOCer, I'm not a fan of yet another new colour in Technic: I'd much rather see new moulds in existing colours than existing moulds in new colours (like the Panel Plate 5 x 11 x 1 Tapered). This is why I didn't bother getting the 42039 24 Hours Race Car or the 42069 Extreme Adventure.

  6. I have checked the recently published new building instructions for 42099. Why are there only 944 parts shown instead of the official 958 pieces?

    1. TLG do not always publish all of the new parts. So the missing ones are likely to be the new ones. We don't know why this is, it used to happen more often. Maybe everyone is still on holiday :)