9398 - Lego Technic 4x4 Crawler

[davidmull]

Even tho I like to keep my sets as Lego intended, is there any mods people are thinking of doing? I'm not sure how much u can improve a great set like this tho :)

[dr_spock]

If I get the set, I may change the body. I am not too keen about the colour scheme.

[5150 Lego]

I agree, I can't believe that people are complaining about this. Obviously everyone thinks that they can build a better model. This is pretty darn impressive for having such a low part count.

You don't get it. No one is saying they can build a better model. People are just pointing out things they either dislike or weren't expecting. I really don't see why that's so hard for some to understand.Rome through all the other reviews in the various themes throughout eurobricks and you will find several people in each thread review that find something they either dislike or would have liked to see done different. I don't see why this model should be free of the same fair criticism.

I agree with this. Reviews, like everything else posted on this site, are just opinions and everyone's opinions can legitimately differ because different people value different things. When I write a review, I try to not only offer my opinion but also the reason for my opinion. This gives people the information they need to form their own. Not only do I not have any problem with someone disagreeing with my opinion, but I actually like to hear what factors make someone think differently.

I think the only time it devolves into trolling is when someone just says something like "I don't like it" with no information. OK, why don't you like it? With nothing to back up the opinion it doesn't mean anything and only results in people arguing about the relative substance of nothing. Like just happened in this thread!

I'm glad you understood what i was trying to convey. I have nothing but the up most respect for you. I appreciate the reviews you have done as well as the future reviews you will do. Its not easy designing a LEGO model that will appeal to the masses and still be profitable. IMO its both the praise and criticism that lets TLC give us better and better models each year.

[efferman]

five minutes ago my 9398 has arrived and the tires seems to be identical. only a oily film is on the surface. i think there is a need to wash them

[mrklaw]

@allanp,

I too would have liked to see the motors in the traditional "under hood" position instead of the axles. I agree that it isn't as realistic and does look a bit odd and bulky. BUt i do understand the reasoning for doing so. Technic axles universal joints aren't very strong and my guess is driving all 4 tires would have caused them to snap under serious load. Yes, they could have geared down even more than they already have to compensate, but that would have made the model much slower.

For a crawler, having motors on each axle is a good thing, so it is 'traditional' for that class of vehicle.

[efferman]

ok,power is enough, but there is a little problem with the diffs

the name 4x4 offroader is plausible, but please stop call em crawler

Edited July 3, 2012 by efferman

[DLuders]

@ efferman: Thanks for your video! Do you think it is possible to modify the 9398's design to have LOCKING DIFFERENTIALS?

[efferman]

i think not, but we can remove the diff and use a simple gear and going trough connection. but i think also that the center of gravity is too high for heavy terrain

[davidmull]

i think not, but we can remove the diff and use a simple gear and going trough connection. but i think also that the center of gravity is too high for heavy terrain

Have u tried it with power puller wheels?

[efferman]

no, because i dont own power puller wheels

[davidmull]

no, because i dont own power puller wheels

Can u not put on the cab for extra weight and use the tires that came with it?

Would be nice to see it in true form!

[efferman]

when i have finished it, i will test it with used original tires, to see its true performance

[5150 Lego]

For a crawler, having motors on each axle is a good thing, so it is 'traditional' for that class of vehicle.

Please show me one real vehicle were the motors are attached to the axles. I'd really like to see this. I understand why TLC did it for there model. But it doesn't make it "traditional". Especially when compared to real rock crawlers. Some RC rock crawlers do have motors attached to the axles, but as RC rack crawlers progressed, most companies have strayed away from this setup.

[raus]

Please show me one real vehicle were the motors are attached to the axles. I'd really like to see this. I understand why TLC did it for there model. But it doesn't make it "traditional". Especially when compared to real rock crawlers. Some RC rock crawlers do have motors attached to the axles, but as RC rack crawlers progressed, most companies have strayed away from this setup.

, Universal joints Lego do not support high torque for a vehicle like this .. Rc crawler companies do so for reasons of cost, since it takes two engines, two cuts and a dual motor esc;

[GuiliuG]

Remove differential is the worst thing you can do at my eyes. Before, all trial trucks used NO differentials but it was a mistake for me. Turning radious is just ridiculous without differentials and you can't maneuver your vehicle proporly.

Don't know if you have already participated in a trial competition and see the difference between trucks with differentials and without but it's astonishing how the differential allow a smooth drive!

So, yes, differentials hamper performances but with good suspensions, tires are still always in contact with the ground. You should also see that your obstacles are just enormous, (bigger than the diameter tire) which explain why it can climb your course !

Edit : yes Raus, lego joint are too weak. You can build your own but they will be bigger or use a rond plate at the end to consolidate it. All in all, lego are just plastic parts... One thing which is strange is that, during fana'briques trial truck competition I have broken a joint where torque was the lowest... One of these :

Edited July 3, 2012 by GuiliuG

[5150 Lego]

, Universal joints Lego do not support high torque for a vehicle like this .. Rc crawler companies do so for reasons of cost, since it takes two engines, two cuts and a dual motor esc;

Yes, i understand this. I covered this in my post previous to my last about how fragile LEGO universial joints are.

Remove differential is the worst thing you can do at my eyes. Before, all trial trucks used NO differentials but it was a mistake for me. Turning radious is just ridiculous without differentials and you can't maneuver your vehicle proporly.

Don't know if you have already participated in a trial competition and see the difference between trucks with differentials and without but it's astonishing how the differential allow a smooth drive!

So, yes, differentials hamper performances but with good suspensions, tires are still always in contact with the ground. You should also see that your obstacles are just enormous, (bigger than the diameter tire) which explain why it can climb your course !

Suspension flex and gearing are huge when it comes to getting over obsticles. Ultimatley, if you could figure out a way to lock the diffs via remote then you'd have it made. I remember seeing someone did it a while ago, but the model was rather big. Bigger than Truck trial specifications.

[timslegos]

I think we might have been expecting to much from a set made by TLG. Obviously a official set is not going to be made to be able to climb such steep slopes.

tim

[allanp]

Remove differential is the worst thing you can do at my eyes. Before, all trial trucks used NO differentials but it was a mistake for me. Turning radious is just ridiculous without differentials and you can't maneuver your vehicle proporly.

Don't know if you have already participated in a trial competition and see the difference between trucks with differentials and without but it's astonishing how the differential allow a smooth drive!

So, yes, differentials hamper performances but with good suspensions, tires are still always in contact with the ground. You should also see that your obstacles are just enormous, (bigger than the diameter tire) which explain why it can climb your course !

Edit : yes Raus, lego joint are too weak. You can build your own but they will be bigger or use a rond plate at the end to consolidate it. All in all, lego are just plastic parts... One thing which is strange is that, during fana'briques trial truck competition I have broken a joint where torque was the lowest... One of these :

Those UJs running along the centre are actually under the most stress because they are providing force to two UJs per axle with less than a 1:2 differencial gear reduction (20:28 is a tiny reduction for a diff), yet another gripe I have with their parts designs

[efferman]

..... I have broken a joint where torque was the lowest... One of these :

what can we do when a joint breaks during inserting a axle?

your differential theorie is interesting and on normal tracks i give you a full agree, but on tracks with different grip on every tire it will stuck on the easiest obstacle. so i think it would be the best solution if every tire has its own motor.

btw, is it only me or is there something wrong in one of the following pictures?

101_9406 von efferman auf Flickr

why can lego not produce tires with good proportions? every time these ugly spheric ballons

[allanp]

Oh man do I love those tyres!

Anyway, in the past I have strengthened UJs by tightly wrapping fine sewing thread around the ends. Makes the ends very strong.

[Jetro]

why can lego not produce tires with good proportions? every time these ugly spheric ballons

I fitted the Unimog tyres on mine :D

[GuiliuG]

Oh Allamp, it's indeed evidend why these u-joints break ! Thanks for opening my eyes :)

Locking differentials would be very complicated to integrate with the parts currently avalaible. A trial truck with a central articulation could be the solution but it would be more heavy. Naturally, it depends which obstacles you want to pass with your trucks but I think differentials are the best solution.

[Zerobricks]

Still using diffs in an offroader INMHO is a bad idea. They may work in ideal situations, but real mud, dust, rocks and grass are not ideal. Closes thing to a perfect mix of maneuverbility and perforamnce I think is using 2 motors, one for each side of the truck's wheels like my Lynx used.

[davidmull]

what can we do when a joint breaks during inserting a axle?

your differential theorie is interesting and on normal tracks i give you a full agree, but on tracks with different grip on every tire it will stuck on the easiest obstacle. so i think it would be the best solution if every tire has its own motor.

btw, is it only me or is there something wrong in one of the following pictures?

101_9406 von efferman auf Flickr

why can lego not produce tires with good proportions? every time these ugly spheric ballons

I like ur tires but they do look a little narrow, I must admit I'm a bit let down it wouldn't climb ur course but it was a bit too extreme , have u tryed a lighter course on standard set up yet?

[efferman]

ok, on a slick ascending slope it works till 30°, then the rear axle motor goes into stall, because the frontaxle has no grip.

obstacles, my foot for example, against a single tire, are possible till 5cm height.

overall is grip the problem. with my ansmann tires is much more possible. the vid which was posted by anio shows good the possible performance.