42129 - 4x4 Mercedes-Benz Zetros

[syclone]

Wow, that's an honest review stating cold facts from top to bottom. Even more impressive is the amount of negative comments made towards the set - most want C+ gone or simply find it boring lol.
For a partspack - no way it's worth it. Even if you manage to sell off the electronics (good luck) the Tow Truck is much better value, both as a set and parts alone.

Nonetheless I have found a positive side to this set - I now started to like 42070  .

[Ngoc Nguyen]

Aaand Grohl has started working on the B model for this set.

[Maaboo the Witch]

5 hours ago, Ngoc Nguyen said:

Aaand Grohl has started working on the B model for this set.

Yay... hopefully this model won't chew up its differential if you drive it too hard.

[Gray Gear]

1 hour ago, Maaboo35 said:

Yay... hopefully this model won't chew up its differential if you drive it too hard.

Another point where a 6x6 would have been better. A 3rd axle would not also helped with traction, but also spread the load over a 3rd diff and wheel hubs.

[Citromon]

4 hours ago, Gray Gear said:

Another point where a 6x6 would have been better. A 3rd axle would not also helped with traction, but also spread the load over a 3rd diff and wheel hubs.

I have got the impression that initially they wanted to make three axles, but the two L motors simply couldn't manage the additional load, which affected the off-road ability of the model. And considering that that's the main function, they just gave up the idea. 

Edited August 2, 2021 by Citromon

[Void_S]

39 minutes ago, Gray Gear said:

Another point where a 6x6 would have been better. A 3rd axle would not also helped with traction, but also spread the load over a 3rd diff and wheel hubs.

It depends on how the drivetrain is built (i know 3 options but even more may exist):

1. "Through" 2nd axle:
   Engine > Gearbox > Distribution box with central diff > 1st axle diff > Front wheels
                                                                                     └> 2nd axle diff > 2nd axle wheels
                                                                                                             └> 3rd axle diff > 3rd axle wheels
   This sheme has 4 diffs (1 central, between front/rerar axles and 3 per-axle diffs) and a logic of always locked rear tandem diff.
2. "Rear tandem diff":
   Engine > Gearbox > Distribution box with central diff > 1st axle diff > Front wheels
                                                                                     └> rear tandem diff
                                                                                                             ├ > 2nd axle diff > 2nd axle wheels
                                                                                                             └> 3rd axle diff > 3rd axle wheels
   This sheme has 5 diffs (1 central, between front/rerar axles,1 at the rear "center" and 3 per-axle diffs) and a logic of all opened connections.
3. "3-output distribution box":
   Engine > Gearbox > Distribution box with central diff(s) > 1st axle diff > Front wheels
                                                                                       ├ > 2nd axle diff > 2nd axle wheels
                                                                                       └> 3rd axle diff > 3rd axle wheels
   For this scheme, I unfortunately, have no so many details but know that it exists  

[efferman]

47 minutes ago, Gray Gear said:

Another point where a 6x6 would have been better. A 3rd axle would not also helped with traction, but also spread the load over a 3rd diff and wheel hubs.

Not with the hard shocks and short suspension travel. It makes no sense to have 3 Axles when one axle is most of time in the Air.

[1gor]

14 hours ago, AVCampos said:

I view it as a parts pack. And, in that respect, apart from the hard-to-reuse bright green elements, I actually like it.

Inventory is here https://rebrickable.com/sets/42129-1/4x4-mercedes-benz-zetros-trial-truck/#parts

but so far I can not find tires on sale (separately)

[nerdsforprez]

I just finished @rm8's review.  Good stuff.  He also put new RC tires on the Zetros to see it crawl.  

One, more thirty-thousand ft high, question I have though is what exactly is the appeal of trial trucks in general for Lego AFOLs?  I mean in the context of rock-crawlers, that as far as I can see do the exact same thing but are far superior? 

I mean in real life the appeal for a trial truck is present because they provide something unique.  Technically speaking, large trucks able to ford any terrain is appealing because they can carry cargo, unlike rock crawlers.  Trial truck competitions don't need to do that, but I understand the sprit.  

But for just purely crawling?  Or purely just having the ability to go through muggy terrain?  Why not built/release a better crawler? 

 

I am about to release a video that compares two new renditions of rock crawlers originally built by another AFOL here on this site.  His design, with my tweeks, are so much superior to the Zetros its not even close.  I was going to buy the Zetros, just for the fun of driving it.  But now I don't think so.  It can't match crawlers in its play ability.....Crawlers versus trials trucks are so much different of a design.  I think a crawler, properly designed can out-perform a trail truck in most scenarios (given design and gear ratios are true to both designs) 

[Bartybum]

53 minutes ago, nerdsforprez said:

Why not built/release a better crawler? 

To my understanding Grohl and the Technic team had wanted to do a trial truck for quite a while now, and so they presumably took the opportunity to do so once the heavy duty diffs and planetary hubs came into existence.

I do hope in the future that we'll get a proper lighter weight rock crawler with high suspension travel.

[Ullum Zurt]

1 hour ago, nerdsforprez said:

One, more thirty-thousand ft high, question I have though is what exactly is the appeal of trial trucks in general for Lego AFOLs?  I mean in the context of rock-crawlers, that as far as I can see do the exact same thing but are far superior? 

I mean in real life the appeal for a trial truck is present because they provide something unique.  Technically speaking, large trucks able to ford any terrain is appealing because they can carry cargo, unlike rock crawlers.  Trial truck competitions don't need to do that, but I understand the sprit.  

But for just purely crawling?  Or purely just having the ability to go through muggy terrain?  Why not built/release a better crawler?

I've also wondered this. Dedicated rock crawlers >>> trial trucks

1 hour ago, nerdsforprez said:

I am about to release a video that compares two new renditions of rock crawlers originally built by another AFOL here on this site.  His design, with my tweeks, are so much superior to the Zetros its not even close.  I was going to buy the Zetros, just for the fun of driving it.  But now I don't think so.  It can't match crawlers in its play ability.....Crawlers versus trials trucks are so much different of a design.  I think a crawler, properly designed can out-perform a trail truck in most scenarios (given design and gear ratios are true to both designs) 

Looking forward to this video. Do share it here on EB.

[jorgeopesi]

Instructions are already available.

[Teo LEGO Technic]

I think something I would love to see from LEGO is a real heavy-duty differential where the perpendicular gears make contact over an entire half stud if not full stud, compared to the current ~1/3 stud. It would allow to put so much more load on the diff without having to use for example the 4-tooth yellow gears which kill torque with their high friciton.

Edited August 3, 2021 by Teo LEGO Technic

[pleegwat]

20 minutes ago, jorgeopesi said:

Instructions are already available.

As is the C+ profile. Augmented reality mode just won't work for me - I aim the camera at the model when it tells me to and it just doesn't proceed from there. Guess daylight isn't well-lit enough, or it only works on a plain white surface.

[AVCampos]

Your phone needs to be compatible with a Google AR library: AR Core or something like that.

[rm8]

Hello, yes my review with autosubtitilesi s available here,

thing you may be intereseted in:

04:54 Trying new wheels for other models 06:27

27:52 Best tires for a model

32:05 Trying on different wheels on the Zetros

 

 

[nerdsforprez]

20 hours ago, Bartybum said:

To my understanding Grohl and the Technic team had wanted to do a trial truck for quite a while now, and so they presumably took the opportunity to do so once the heavy duty diffs and planetary hubs came into existence.

I do hope in the future that we'll get a proper lighter weight rock crawler with high suspension travel.

Yes but why?   As far as I can tell, to just say you built something that can climb a steep, EVEN, slope?  I don't really get it...

5 hours ago, rm8 said:

Hello, yes my review with autosubtitilesi s available here,

thing you may be intereseted in:

Thxs for the video.   Watched it all.  As far as I can tell, the one conclusion I walk away with this set is it was built for one thing in mind.  Climbing and EVEN, smooth slope.  This it does very well.  

But, because of its small tires and long wheelbase anything that resembles actual terrain will be a challenge.  Even a slope, but with some natural variance to it will be difficult.  

So to me this is not a trial truck at all. I was very excited to get this set, but now I am not sure at all.  If I do, it will be for a parts pack only, and I likely will not even build the actual set. Definitely not using the tires it came with (which are a good portion of why it is so expensive in the first place).  

19 hours ago, Ullum Zurt said:

I've also wondered this. Dedicated rock crawlers >>> trial trucks

Looking forward to this video. Do share it here on EB.

Yup, I will.  Waiting  for some better outdoor lighting.  Hopefully this weekend....

[nerdsforprez]

Can anyone let me know if the gearing of the Zetros is such that when going downhill there is enough resistance to keep the vehicle at a stopped, or "braking" position?  

[2GodBDGlory]

1 hour ago, nerdsforprez said:

Can anyone let me know if the gearing of the Zetros is such that when going downhill there is enough resistance to keep the vehicle at a stopped, or "braking" position?  

I built a modified PF version with balloon tires, but when I was doing slope testing, the model would slide down the slope rather than backdrive the motors. Beyond this loose testing, I can say that I am quite confident that it is not heavy enough to backdrive the motors going downhill.

[nerdsforprez]

26 minutes ago, 2GodBDGlory said:

I built a modified PF version with balloon tires, but when I was doing slope testing, the model would slide down the slope rather than backdrive the motors. Beyond this loose testing, I can say that I am quite confident that it is not heavy enough to backdrive the motors going downhill.

Which Balloon Tires?  If they are larger than the official tires when you are right.  If smaller, there is a chance that a larger diameter tire would do the trick.  

[Ngoc Nguyen]

28 minutes ago, 2GodBDGlory said:

I built a modified PF version with balloon tires

I had a mod with balloon tires that you can try 

https://rebrickable.com/mocs/MOC-84984/nguyengiangoc/42129-pf-conversion-l-motor-steer/

[2GodBDGlory]

22 hours ago, nerdsforprez said:

Which Balloon Tires?  If they are larger than the official tires when you are right.  If smaller, there is a chance that a larger diameter tire would do the trick.  

I was using the ones with virtually the same diameter as the tractor ones.

I later upgrades to 107mm tractor tires, though...

[Kostq]

Sorry if I've missed a post - has anyone tried Zetros tires on the Arocs model?

There's something not-to-scale every time I look at 42043. And it's the tires for me.
Just wondering how it would look with the Zetros or the 42124 Buggy tires on it.

Edited August 23, 2021 by GTS

[kbalage]

On 8/19/2021 at 7:23 PM, nerdsforprez said:

Can anyone let me know if the gearing of the Zetros is such that when going downhill there is enough resistance to keep the vehicle at a stopped, or "braking" position?  

Depends on the angle of the slope, but it slips rather than rolls. 

[nerdsforprez]

2 hours ago, kbalage said:

Depends on the angle of the slope, but it slips rather than rolls. 

Great.  As I experiment myself, not with this set but with other crawlers this is very important for climbing...