What would work better: 2 XL motors or 4 L motors?

[Carefree_Dude]

I have a train that I want to power via PF motors. Currently, I can either fit 2 XL motors or 4 L motors inside the boiler. 

Which of these setups would provide more overall power and pull a longer train? 

[Toastie]

It will very much depend on how you will deliver the torque of the motors to the wheels. With more or less "direct" delivery from the XL motors, friction losses are certainly minimized. With more than 2 wheel stets powered, the overall traction will be better. So the answer to your question is: It depends on your construction.

Best
Thorsten 

[sirslayer]

From my own experience with the PF motors, 2 x XL motors vs 4 L motors comes down to if you need speed (4 L motors)  if your model is light enough or torque (2 x XL motors)  if you planned to haul heavy loads!!

[suffocation]

Also bear in mind that 2 XLs can be powered efficiently with 1 battery box; 4 Ls will also work but will be underpowered. This, of course, can be easily solved using a BuWizz unit powering 2 Ls per channel.

[andythenorth]

A train with 4L would be...over-powered for every situation I can think of 

4L motors can move this no problem, it's about 7KG.

Edited October 16, 2019 by andythenorth

[suffocation]

6 hours ago, andythenorth said:

4L motors can move this no problem, it's about 7KG.

At what speed, though?

And is that good ol' British milk? Best I've ever had

[andythenorth]

13 minutes ago, suffocation said:

And is that good ol' British milk? Best I've ever had

Yup.

There are various videos here, not all the same gear ratio though.  Can't remember all the details. 

https://www.flickr.com/photos/andythenorth/albums/72157649987860696

There's a test rig with 8 L motors here, failed experiment, quite lolz 

https://www.flickr.com/photos/andythenorth/14071162377/

And for the original poster, just two of the older RC train motors will move a fair size train quickly. https://www.flickr.com/photos/andythenorth/15097651796/in/dateposted-public/  Sadly that video does not include the epic crash where my two-year old sat down on the train.  Maybe I should add that.

 

 

Edited October 16, 2019 by andythenorth

[suffocation]

Wow, the motors are actually geared UP there and still get the job done brilliantly. Pretty impressive and makes me rethink how I use motors.

Thanks, Andy

[andythenorth]

When performance is the goal, one motor per wheel is quite a ruthless approach    

I have tried the alternatives with realistic transmissions, and hard-coupled XL motors and crap.  It's quite lolz how much that stresses Technic parts, and how the performance is never stellar   

There's a truck here with 3x XL, differentials, and pneumatic lockers https://www.flickr.com/photos/andythenorth/albums/72157633468817167 

This is is version 2, it kind of works.  Version 1 had 2 hard-coupled XL and a proper transmission with 2-speed gearbox.  Version 3 will be L motors, driving direct where possible.

 

Edited October 16, 2019 by andythenorth

[Carefree_Dude]

So, I modified my train quite a bit, and I can now fit FOUR XL motors inside the boiler. Is it safe to assume I will need something like buwizz to actually deliver full power to these things? 

 

 

[suffocation]

You'd need 1 BuWizz unit or two Lego battery boxes. But you probably don't need 4XLs unless the train's really heavy and going uphill; even then, it's also a matter of how you transfer power from the motors to the wheels.

[sirslayer]

i would like to share this youtube video with my MOC with 2 x XL motors and a the AA Lego battery box. The MOC is based of from the Lego set 8273 Off road truck with a bit of modernization.. It is small truck scaled smaller then the Lego 42093 Corvette so the performance is very good with the 2 x XL motors...  

 

 

 

 

 

[Toastie]

On 10/16/2019 at 7:13 PM, Carefree_Dude said:

So, I modified my train quite a bit, and I can now fit FOUR XL motors inside the boiler. Is it safe to assume I will need something like buwizz to actually deliver full power to these things?

On another thought: When you need the 4 XL's to really kick in, what are your power delivery plans? Whatever brick is doing the speed control is fine, but these need to be fed. For how long do you want to operate your train? And will it be all LEGO? In that case you'll need to stack up some battery boxes somewhere, I believe.

Regards,
Thorsten