Answers.Body: <p>The basic premise of your idea is sound: the metal-wheeled train motor can indeed receive power from the track and forward it to the studs on top of it. Then an extension wire can be used to power another motor. The only possible problems I might anticipate are:</p>
  <ol>
  <li><p>possibly mismatched velocity (due to either voltage drop, different internal gearing or different wheel diameter)</p>
  </li>
  <li><p>the operational limits of the</p>
  <ul>
  <li>power supply unit (shouldn't be an issue, as two metal-wheeled train motors can run on a track powered by a single supply)</li>
  <li>or the pass-through capacity of the 9V train motor (as it was designed to pass through enough juice to power lights, not motors with their significantly larger consumption)</li>
  </ul>
  </li>
  </ol>
  <p>The good news is that none of these are showstopper issues even if they prove to be a problem, and you can quite easily test all of them - so let's start building :)</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2023-03-24T13:09:18.590Z
Answers.Text: Also, besides mismatched velocity, mismatched direction, with 9V this can be adressed by turning one of the connectors 90 degrees (in the right direction it reverses polarity)
Answers.UserDisplayName: Michael Verschaeve
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2023-03-24T12:00:40.370Z
Answers.LastActivityDate: 2023-03-24T12:00:40.370Z
Answers.UserDisplayName: zovits
Body: <p>I'm building a MOC based on the <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?S=10219-1#T=S&amp;O=%7B%22iconly%22:0%7D" rel="nofollow noreferrer">10219 Maersk Train</a>, but going for the classic track power 9V system given the removal of need for batteries and slowly increasing availability of new 9V parts from third-party supplier FX Bricks.</p>
  <p>I was wondering about dual-motoring my locomotive, and hit upon the idea of using the <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?P=x1688&amp;idColor=11#T=C&amp;C=11" rel="nofollow noreferrer">Technic axled motor</a> from the 9V RC era (as used in the <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?S=7898#T=S&amp;O=%7B%22iconly%22:0%7D" rel="nofollow noreferrer">Cargo Train Deluxe 7898</a> set), linking it to track power via a <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?P=5306bc015&amp;idColor=11#T=C&amp;C=11" rel="nofollow noreferrer">9V extension wire</a> attached to the power studs atop it and going to those atop the classic 9V track powered motor.
  My thought is that in using the motor with silicone traction tires in addition to the <a href="https://www.bricklink.com/v2/catalog/catalogitem.page?P=590#T=C" rel="nofollow noreferrer">metal-wheeled classic motor bogie</a>, it may be possible to get even better traction and pulling power.</p>
  <p>I'm still learning about LEGO trains after getting back into them many years later, so I'm not sure if the transformer could handle it (other folks I've seen have said that the controller overheats running two motors for a long period of time), or if those top power studs can even transmit the power required for running another motor.</p>
  <p>Can the components be used as I'm thinking, or have I gone wrong in my thought process somewhere?</p>
  
Tags: <motor><trains><moc><9v>
Title: Can 9V train motors be linked and work together via the top power stud connection?
UserDisplayName: Jazzyamx
ThreadText: # Can 9V train motors be linked and work together via the top power stud connection?
  
  (Asked by: username_0 on 2023-03-24)
  
  I'm building a MOC based on the [10219 Maersk Train](https://www.bricklink.com/v2/catalog/catalogitem.page?S=10219-1#T=S&O=%7B%22iconly%22:0%7D), but going for the classic track power 9V system given the removal of need for batteries and slowly increasing availability of new 9V parts from third-party supplier FX Bricks.
  
  I was wondering about dual-motoring my locomotive, and hit upon the idea of using the [Technic axled motor](https://www.bricklink.com/v2/catalog/catalogitem.page?P=x1688&idColor=11#T=C&C=11) from the 9V RC era (as used in the [Cargo Train Deluxe 7898](https://www.bricklink.com/v2/catalog/catalogitem.page?S=7898#T=S&O=%7B%22iconly%22:0%7D) set), linking it to track power via a [9V extension wire](https://www.bricklink.com/v2/catalog/catalogitem.page?P=5306bc015&idColor=11#T=C&C=11) attached to the power studs atop it and going to those atop the classic 9V track powered motor.
  My thought is that in using the motor with silicone traction tires in addition to the [metal-wheeled classic motor bogie](https://www.bricklink.com/v2/catalog/catalogitem.page?P=590#T=C), it may be possible to get even better traction and pulling power.
  
  I'm still learning about LEGO trains after getting back into them many years later, so I'm not sure if the transformer could handle it (other folks I've seen have said that the controller overheats running two motors for a long period of time), or if those top power studs can even transmit the power required for running another motor.
  
  Can the components be used as I'm thinking, or have I gone wrong in my thought process somewhere?
  
  **Tags:** motor, trains, moc, 9v
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2023-03-24. Score: 2 | Accepted answer
  
  The basic premise of your idea is sound: the metal-wheeled train motor can indeed receive power from the track and forward it to the studs on top of it. Then an extension wire can be used to power another motor. The only possible problems I might anticipate are:
  
  1. possibly mismatched velocity (due to either voltage drop, different internal gearing or different wheel diameter)
  2. the operational limits of the
  
     * power supply unit (shouldn't be an issue, as two metal-wheeled train motors can run on a track powered by a single supply)
     * or the pass-through capacity of the 9V train motor (as it was designed to pass through enough juice to power lights, not motors with their significantly larger consumption)
  
  The good news is that none of these are showstopper issues even if they prove to be a problem, and you can quite easily test all of them - so let's start building :)
  
  > **Comments:**
  > **username_2**: Also, besides mismatched velocity, mismatched direction, with 9V this can be adressed by turning one of the connectors 90 degrees (in the right direction it reverses polarity)  
  
  ---
  
  