amorti

If the weight is the problem then yes an extra motor will help. There's a limit to how much power one battery can put out. What exact components do you have for battery and RC? if IR receiver, V1 or V2? Do all the motors have to turn (under a load) at the same time?

Depends. If the single L motor is being slowed down significantly by the weight of the vehicle, then yes. If not, then probably no. In either case, it will accelerate quicker with two motors than with one. Other ways to make it quicker: change the gearing, get the Chinese extra power motors, get a buwizz for increased voltage = more rpm.

So, the postman came today. The parts of DarkIce are not exactly cheap, as you can see here! Shipping from UK to Malta costs £10, I guess other European destinations are the same. But definitely quality parts: The company only offers odd lengths of axles. I specially requested 2 * 4L axles, because it doesn't work with any odd length. Unfortunately they are about 2mm longer than Lego axles. The colleague at DarkIce told me when I asked, that they add a 1mm rounding on both sides to protect plastic parts. Unfortunately, the 4L metal axles do not fit for this reason. No worries, I took a plastic axle. Either that holds or I'll grind away the 4 * 1mm roundings later. The nice thing about this extra length is that in the end you have a 5.5L from a 5L axle and can mount the hubcap nicely. So, do I recommend these? Yes! Either you can use these joints with plastic axles (which are then scrap afterwards because of the grub screw), or you order 2 * 5L metal axles with, and 2 * 4L which I'm sure they'd do to a specified custom total length of 32mm on request. If you're firing up the lathe anyway, what does it matter if it's 4L plus rounding or 4L including rounding? Otherwise, if you can drill out joints from the RC world to 4.8mm at home, this is also a good solution.

The most fun I've had building Technic was @Didumos69greyhound. Every connection and brace was a joy, all in system, all clever, all necessary. This model shares a lot of that philosophy, by the look of it. @KevinMoo forklift was right up there, too. Lots of Technic all with purpose, in a very compact model for how many functions it has.

Looks cool indeed, and works better off-road than something its scale has much right to. Good work!

It's a live axle suspension, the wishbones aren't meant to move.

Awesome!

@rm8 Thanks! Please let the group know if it ever becomes a commercial product. There's real potential in it. Is longer wires a good idea? The heat would be from resistance in the cable. Add cable, add resistance...

My questions would be: 3S or 2S lipo; what can it use? How many amps can one unit supply? How many motors can it power? I want it to power 4* Chinese "+30%" L motors. Can they be paired to increase output?

Anyone got one of these? Or speak Russian well enough to understand what it's about? I think I'd like to try one, looks like a great idea. https://m.vk.com/24rcbrick @rm8?

@benxz Just put the YouTube link in the text box, the forum software is smart enough to work it out. Didumos has said he's broken 2 Lego plastic U-joints, and there's several reports of that happening in the thread. As it's only 2, didumos clearly has more mechanical sympathy than we do, and no "leaden foot"! I don't doubt him, and happily accept that if you have original (less torque) Lego motors and you drive it considerately with gentle acceleration, the original U-joints will last at least a little while.

@1980SomethingSpaceGuy - thanks for the tip! This makes me happy :)

So here's my findings after testing each solution, ranked in order of success and some embedded links: Plastic universal joints: when driven with the Chinese +30% motor M-003 on anything other than Slow, these last maximum of a few minutes. The rubber band trick stops them splitting, so they spread the yokes and the disc flies out, never to be seen again. The 30% extra torque of these Chinese motors might be the reason they're fine for @Didumos69 but no good for me. Anyone thinking about using these motors needs to be aware, they're heading down a rabbit hole of finding the next weakest link. I know I need to make a video of mine driving over rough terrain to show this claim, but it's not easy when you need your phone to run BrickController2. AliExpress metal universal joints: These are sloppily built with a soft alloy body, the disc is brass/bronze, and the pins are steel. There is around 1/16 turn of play right from the start and on mine a few km of driving (driving Greyhound while walking Myhound ) saw 1/8 turn of freeplay and a horrible noise, but at least they didn't fail catastrophically. However, some users have reported they can fail catastrophically, and the sloppy tolerances mean I can believe it. Lego 42099 CV joints: actually these aren't bad .For any Lego purists, this is the best solution because they will not fail catastrophically like the two above, although they will wear down with use (image shows early stages!). I think a lot of the wear they suffer is because of the misalignment inherent in small ball-joints. In any case, only the ball part of the joint gets worn and it's not so hard to replace nor too expensive. eBay metal universal joints: I've just ordered these and as they are made of plated steel, I have hopes that they'll be the most durable solution yet. They're 4mm RC universal joints bored out to 4.8mm such that a Lego axle fits snug. Seller told me it's best to use metal axles (which he also sells, I had to ask for 4L axles specifically and pay an extra £2.50 each as a custom machining fee on top of a 5L axle's normal price) as you need to screw the joint down onto the axle and even if that holds, your axle will be scrap afterwards.

I think we do agree, in fact :) I don't see a model this size can be called Technic if it doesn't have at least a fake motor. The Corvette didn't have much more than that, but it did have that.Functionally, this is closer to the Mustang. So: Lego couldn't sell it as Technic because it has no functions, but also not as Creator, because it's made with Technic panels.

Fancy!

Depends where you are and how much shipping you pay. Genuine L motors are usually around 11€ each. Knockoffs are less, at least before shipping and customs duty, but can get to more or less the same money. However you can't get genuine Lego L motors with 30% more power, nor 30% more power and 300% more rpm, so if that's what you want, you have to play Marco Polo.

Buwizz is testing a higher powered buggy motor.

You need a controller. You'll be glad you got one, driving your models is so much more fun with tactile controls, than using a screen like the buwizz or sbrick app where you either have to look at the screen instead of the model, or your thumb keeps missing the sliders

Well, they're a lot stronger than Lego's plastic u-joints, but due to poor design and cheap materials, they're still a wear part.

Worth looking into brickcontroller2, otherwise you'll be driving it with your phone, then have to put it down to pick up PF remotes to activate the other stuff. BC2 could do that all with one pad, eg joysticks for driving then the arrow buttons and fire buttons for your other 'digital' functions up and down. Assuming you have an s brick and a gamepad already, ofc.

Fancy! Brickcontroller2 to join them up?

What's up with the c+ hub and PF motors?

@kbalage now that is quick ;) I think if I wanted to RC a big heavy car to go quickly, I'd try to build @Madoca 1977's Icarus drive unit in there. It's an amazingly efficient way of getting 4*L motors to power an axle, and increasing the speed 3 times before it gets to the differential. Two buwizz will give the maximum current those motors can draw. One won't quite do that. If you aren't a purist, there are some new Chinese motors which give around 30% extra power over Lego motors. These will help your cause. They also draw more current and you'd definitely need the pair of buwizz for them. They also have 1,400rpm L motors, with which you could run the Icarus drive train with 1:1 gearing instead of 3:1, to increase speed and reduce torque in the drivetrain. Or use those high speed L motors and the new planetary hubs. These are stronger than the old hubs, and again when you increase the speed you decrease the torque. NB: All above, not for purists.

It does look nice, but to be brutal, this is not a Technic model, it's a creator expert model built with Technic panels. Lego won't pick it up through Ideas, because they wouldn't how to sell it.