Lego Land Rover Defender jerky pistons movement 

More and more that I see problems with Lego Land Rover Defender, more I think that the Lego set was made by real Land Rover engineers

So just like a real Land Rover product.

It’s the 2 u joints; the manual displays the wrong way to connect 2 of those on 1 axis; one of them must be turned 90deg, that’s all. Still not perfect but that is how it is with these joints.

There's basically so much stress on the gearbox that you can just forget that whole block. Rip it out and make a perfect rc conversion on it 👍🏻 makes better use of the amazing suspension anyway

You are not alone guys, maybe because a lot of free space between gears, I don’t know

I had this similarly and did all the recommendations and could only slightly improve things. Later in the Sian I noticed that very individual combinations of 20 teeth tan bevel gear and 12 teeth black bevel gear kind of locked and putting more resistance to the system. It is like there were different generations of this tan gear (some a little bit softer than others) and those only rotate not by turning smoothly but clicking to the next tooth.

Error on page #89 in manual. You should use drawing from page #88 to assemble second joint

Try disconnecting the gray gear that puts the gearbox into reverse.

I have this problem too

Mine does the same damn thing I just removed one of the driveshafts so now it only has one gear but it works ok but whatever you do don’t use oil on the gears it break them and cracks them

I have the same problem like you

Don't want to jinx myself but just got mine a couple weeks ago and it came out perfect. Something isn't lined up right or is to tight.

I have the same problem dude and I rebuild step 1&2 multiple times but it's still there! Reverse gear is fine though 🤦🏻‍♂️

i think it has to much torque and friction, the axles is are twisting intill the force overcomes the friction, then the momentum allows it to overcome the friction, the torque is too high in the wrong places try stepping down the torque in the main system only bumping it up closer to where its needed making the axle with high torque short and less like a spring, instead of from the wheels to the engine is a long axle that can have a micro twist but because of the length its a full revolution at the other end.

Any building error?

Just from what I can notice and issues that I have had with some custom creations, it might be a Lego universal joint, the one that can do a 90 degree pivot. When those pieces are positioned at an angle too steep, they can build resistance and release it, just like shown in this video. I do not have this build, but this may be the cause of it, again I'm just comparing from my problems with builds previously. (The universal joint that can cause this to happen, is just like the one connecting the steering wheel to the steering system in this build).

somets nackerd mate, gear loose

mine its pistons is slow

Ja również mam tego land Rovera ale takowy problem mi się nie zdarzył

Same problem for me!!

Probably u joints are at to much of an angle

Wały Kardana muszą być w tej samej pozycji po obu stronach na obu tych "prętach". Łatwy do naprawienia błąd, miałem to samo.