Answers.Body: <p>Another type of pullback motor has a detailed structural disassembly here: <a href="https://i.sstatic.net/Z9xe6.jpg" rel="nofollow noreferrer">Imgur album</a>.</p>
  
  <p>I think your motor should work mostly the same way, but I wasn't able to source such internal pictures.</p>
  
  <hr>
  
  <h2>LEGO Micro Pull-back Motor Reassembly</h2>
  
  <p><a href="https://i.sstatic.net/7EQkO.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/7EQkO.png" alt="enter image description here"></a></p>
  
  <p>Micro Pull-back Motor Parts</p>
  
  <p>Gear A: Pin shaped like 'E' for attachment to Spring on Chassis
  Gear B: Smallest (of 2) gear with a pin
  Gear C: Largest gear with 2 levels, smaller gear at the bottom, larger gear on top, with teeth for meshing with Axle F
  Gear D: Smallest (of 2) gear with a hole
  Gear E: Medium gear with 2 levels
  Axle Assembly F
  Gear Assembly G</p>
  
  <p>Not shown: 5 X-head screws
  Note: Gear A may be detached from Spring. 
  I attached it such that it won't fall out when flipped upside down.</p>
  
  <p><a href="https://i.sstatic.net/4E3pn.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/4E3pn.png" alt="enter image description here"></a></p>
  
  <p>Install Gear B
  Place Gear B with pin downwards into slot in Gear Assembly G</p>
  
  <p><a href="https://i.sstatic.net/ITBCX.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/ITBCX.png" alt="enter image description here"></a></p>
  
  <p>Install Gear C.
  Place Gear C into the hole in Gear Assembly G.
  The larger gear is on top.
  Gear C will cover Gear B and mesh with it 
  (though Gear B has some play since it is in a slot)</p>
  
  <p><a href="https://i.sstatic.net/pYmLP.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/pYmLP.png" alt="enter image description here"></a></p>
  
  <p>Install Gear E.
  Place Gear E into the small depression in Gear Assembly G.
  The larger gear is at the bottom, and will slide under Gear C.
  There is a pin facing up. Gear E will mesh with Gear B.</p>
  
  <p><a href="https://i.sstatic.net/8trHs.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/8trHs.png" alt="enter image description here"></a></p>
  
  <p>Attach Gear D to the Axle Assembly F.
  Gear D has a small hole which fits on the pin on Axle Assembly F.</p>
  
  <p><a href="https://i.sstatic.net/kxcqn.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/kxcqn.png" alt="enter image description here"></a></p>
  
  <p>Attach the Axle Assembly F to the Gear Assembly Cover G.
  Flip the Axle over. 
  Gear D should stay attached to the Axle Assembly.
  Align the Axle Assembly and snap down on the protruding pin on the Gear Assembly.
  Pinch the two parts (F &amp; G) together at the lower section using thumb and index finger, and try to spin the axle. 
  The gears should only rotate when the axle is spun in one direction, and not the other.</p>
  
  <p><a href="https://i.sstatic.net/OKGXA.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/OKGXA.png" alt="enter image description here"></a></p>
  
  <p>Reattach the Gear Assembly G to the Chassis.
  This step is tricky. 
  You will need to pinch the Gear Assembly to keep parts in place,
  then place the Chassis on top of the Gear Assembly G, and move it around
  until Gear A connects with the correct hole and mesh with the other gears.
  Then, holding everything tightly, flip it over, and start installing and tightening the screws in a diagonal pattern.
  Don't over tighten the screws, you should install at least 3 screws first (one on top, two at the bottom), and test that the spring is engaged with Gear A and you get a pull back action when the wheels are turned.
  After that, install the rest of the screws and tighten all of them.</p>
  
  <p><a href="https://i.sstatic.net/IJ1FO.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/IJ1FO.png" alt="enter image description here"></a></p>
  
  <p>The pull back action works, but I can't figure out how to fix the torque on the spring. 
  So the car is no longer a race car but a jalopy!</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-01-22T13:01:50.337Z
Answers.Text: The imgur link is now also dead, can you upload them again?
Answers.UserDisplayName: Ralph
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-01-22T13:27:54.433Z
Answers.Text: @Ralph Strange, I'm still seeing all of the pictures by clicking on the link.
Answers.UserDisplayName: zovits
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-01-22T15:52:49.327Z
Answers.Text: My mistake, works in Chrome, not in my Firefox, must be something my end, proxy maybe
Answers.UserDisplayName: Ralph
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-01-22T15:53:37.743Z
Answers.Text: @Ralph No problem, glad that got sorted out :)
Answers.UserDisplayName: zovits
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-05-31T19:05:57.540Z
Answers.Text: And now it's broken **AGAIN**.
Answers.UserDisplayName: mindstormsboi
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-01T13:22:54.093Z
Answers.Text: @mindstormsboi It seems to work for me, are you sure it's broken from your perspective?
Answers.UserDisplayName: zovits
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-01T13:59:48.243Z
Answers.Text: @zovits Yes, it's giving the 404 page: https://i.sstatic.net/B6wXF.jpg Why don't you go click the "ask question" button and upload the photo using the markdown imgur uploader? I'm thinking that any other method can cause it to not work.
Answers.UserDisplayName: mindstormsboi
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2020-06-02T08:27:30.750Z
Answers.Text: @mindstormsboi I have embedded the images in the post to take advantage of the SE-Imgur collaboration.
Answers.UserDisplayName: zovits
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2017-10-07T01:54:55.157Z
Answers.Text: The Picasa album you referenced appears to be a dead link.
Answers.UserDisplayName: EJ Mak
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2017-10-07T02:11:58.247Z
Answers.Text: Thanks for the heads-up, it seems Picasa as a service has been retired. I have found the images and reuploaded them to Imgur, hopefully that will not go away soon :)
Answers.UserDisplayName: zovits
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2015-08-04T11:00:32.280Z
Answers.LastActivityDate: 2020-06-02T08:26:31.120Z
Answers.LastEditDate: 2020-06-02T08:26:31.120Z
Answers.UserDisplayName: zovits
Body: <p>I've got the <a href="http://alpha.bricklink.com/pages/clone/catalogitem.page?S=42034-1#T=S&amp;O=%7B%22ii%22:1%7D" rel="noreferrer">42034 Quad</a> for my birthday and it's been really fun to play with technic after so many years.</p>
  
  <p>I am very curious about one thing, though - how does the <a href="http://alpha.bricklink.com/pages/clone/catalogitem.page?P=12787c01&amp;idColor=85#T=S&amp;C=85&amp;O=%7B%22color%22:85,%22ii%22:1%7D" rel="noreferrer">pull-back motor (12787)</a> work and look internally? I'd unscrew mine but I am afraid I'd damage it.</p>
  
  <p>I am guessing it probably uses some kind of spring and/or rubber bands to build the pressure but I'd love to know it's internals precisely.</p>
  
Tags: <piece-information><technic>
Title: How exactly does the pull-back motor (12787) work?
UserDisplayName: Maurycy
ThreadText: # How exactly does the pull-back motor (12787) work?
  
  (Asked by: username_0 on 2015-08-03)
  
  I've got the [42034 Quad](http://alpha.bricklink.com/pages/clone/catalogitem.page?S=42034-1#T=S&O=%7B%22ii%22:1%7D) for my birthday and it's been really fun to play with technic after so many years.
  
  I am very curious about one thing, though - how does the [pull-back motor (12787)](http://alpha.bricklink.com/pages/clone/catalogitem.page?P=12787c01&idColor=85#T=S&C=85&O=%7B%22color%22:85,%22ii%22:1%7D) work and look internally? I'd unscrew mine but I am afraid I'd damage it.
  
  I am guessing it probably uses some kind of spring and/or rubber bands to build the pressure but I'd love to know it's internals precisely.
  
  **Tags:** piece-information, technic
  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2015-08-04. Score: 7
  
  Another type of pullback motor has a detailed structural disassembly here: [Imgur album](https://i.sstatic.net/Z9xe6.jpg).
  
  I think your motor should work mostly the same way, but I wasn't able to source such internal pictures.
  
  ---
  
  ## LEGO Micro Pull-back Motor Reassembly
  
  [![enter image description here](https://i.sstatic.net/7EQkO.png)](https://i.sstatic.net/7EQkO.png)
  
  Micro Pull-back Motor Parts
  
  Gear A: Pin shaped like 'E' for attachment to Spring on Chassis
  Gear B: Smallest (of 2) gear with a pin
  Gear C: Largest gear with 2 levels, smaller gear at the bottom, larger gear on top, with teeth for meshing with Axle F
  Gear D: Smallest (of 2) gear with a hole
  Gear E: Medium gear with 2 levels
  Axle Assembly F
  Gear Assembly G
  
  Not shown: 5 X-head screws
  Note: Gear A may be detached from Spring.
  I attached it such that it won't fall out when flipped upside down.
  
  [![enter image description here](https://i.sstatic.net/4E3pn.png)](https://i.sstatic.net/4E3pn.png)
  
  Install Gear B
  Place Gear B with pin downwards into slot in Gear Assembly G
  
  [![enter image description here](https://i.sstatic.net/ITBCX.png)](https://i.sstatic.net/ITBCX.png)
  
  Install Gear C.
  Place Gear C into the hole in Gear Assembly G.
  The larger gear is on top.
  Gear C will cover Gear B and mesh with it
  (though Gear B has some play since it is in a slot)
  
  [![enter image description here](https://i.sstatic.net/pYmLP.png)](https://i.sstatic.net/pYmLP.png)
  
  Install Gear E.
  Place Gear E into the small depression in Gear Assembly G.
  The larger gear is at the bottom, and will slide under Gear C.
  There is a pin facing up. Gear E will mesh with Gear B.
  
  [![enter image description here](https://i.sstatic.net/8trHs.png)](https://i.sstatic.net/8trHs.png)
  
  Attach Gear D to the Axle Assembly F.
  Gear D has a small hole which fits on the pin on Axle Assembly F.
  
  [![enter image description here](https://i.sstatic.net/kxcqn.png)](https://i.sstatic.net/kxcqn.png)
  
  Attach the Axle Assembly F to the Gear Assembly Cover G.
  Flip the Axle over.
  Gear D should stay attached to the Axle Assembly.
  Align the Axle Assembly and snap down on the protruding pin on the Gear Assembly.
  Pinch the two parts (F & G) together at the lower section using thumb and index finger, and try to spin the axle.
  The gears should only rotate when the axle is spun in one direction, and not the other.
  
  [![enter image description here](https://i.sstatic.net/OKGXA.png)](https://i.sstatic.net/OKGXA.png)
  
  Reattach the Gear Assembly G to the Chassis.
  This step is tricky.
  You will need to pinch the Gear Assembly to keep parts in place,
  then place the Chassis on top of the Gear Assembly G, and move it around
  until Gear A connects with the correct hole and mesh with the other gears.
  Then, holding everything tightly, flip it over, and start installing and tightening the screws in a diagonal pattern.
  Don't over tighten the screws, you should install at least 3 screws first (one on top, two at the bottom), and test that the spring is engaged with Gear A and you get a pull back action when the wheels are turned.
  After that, install the rest of the screws and tighten all of them.
  
  [![enter image description here](https://i.sstatic.net/IJ1FO.png)](https://i.sstatic.net/IJ1FO.png)
  
  The pull back action works, but I can't figure out how to fix the torque on the spring.
  So the car is no longer a race car but a jalopy!
  
  > **Comments:**
  > **username_4**: The Picasa album you referenced appears to be a dead link.  
  > **username_1**: Thanks for the heads-up, it seems Picasa as a service has been retired. I have found the images and reuploaded them to Imgur, hopefully that will not go away soon :)  
  > **username_2**: The imgur link is now also dead, can you upload them again?  
  > **username_1**: @username_2 Strange, I'm still seeing all of the pictures by clicking on the link.  
  > **username_2**: My mistake, works in Chrome, not in my Firefox, must be something my end, proxy maybe  
  > **username_1**: @username_2 No problem, glad that got sorted out :)  
  > **username_3**: And now it's broken **AGAIN**.  
  > **username_1**: @username_3 It seems to work for me, are you sure it's broken from your perspective?  
  > **username_3**: @username_1 Yes, it's giving the 404 page: https://i.sstatic.net/B6wXF.jpg Why don't you go click the "ask question" button and upload the photo using the markdown imgur uploader? I'm thinking that any other method can cause it to not work.  
  > **username_1**: @username_3 I have embedded the images in the post to take advantage of the SE-Imgur collaboration.  
  
  ---
  
  