Alex E Posted December 30, 2011 Hi, I've just dug up my old 7725 and motorized it with a 88002, IR receiver and battery box... All is fine except one very annoying thing - how do I get a center wheel attached to this motor? The original center wheels of the old 7725 motor don't fit, and I couldn't find or think of any piece that can get a wheel onto that hole in that motor... Any help will be greatly appreciated... I can post pictures if anyone's interested. Thanks a bunch. Alex. Share this post Link to post Share on other sites
brickie Posted December 30, 2011 Perhaps a Technic, Axle Pin with Friction Ridges Lengthwise [ very modified ] would do the trick? I be tempted to take a knife to the both ends and hold it in place with a 'soft' glue that will eventually break down so you can use the motor for another purpose. I added a 9V motor to my 7725 and then rebuilt the end carriage with only 2 wheels to match the motor. It looks great. Share this post Link to post Share on other sites
Alex E Posted December 31, 2011 Perhaps a Technic, Axle Pin with Friction Ridges Lengthwise [ very modified ] would do the trick? I be tempted to take a knife to the both ends and hold it in place with a 'soft' glue that will eventually break down so you can use the motor for another purpose. I added a 9V motor to my 7725 and then rebuilt the end carriage with only 2 wheels to match the motor. It looks great. I thought about that, but these holes in the middle of the motor are so inviting - surely they are there for something? Maybe for an adapter pin/axle Lego hasn't come out with yet? Very strange.. Share this post Link to post Share on other sites
Duq Posted December 31, 2011 Nope, you can't use that hole in the side. I believe it was meant for the decorative side part and has no other use. A Technic 3/4 pin won't hold in it. If you would modify a part to fit in it you would wear out the motor casing as the plastic is too soft to withstand the force of a spinning axle. You have two options really for a 3-axle bogie: build around the motor and add a dummy third wheel or forget about this motor, use a PF M or XM motor and build your own bogie. Share this post Link to post Share on other sites
JopieK Posted January 3, 2012 what does LEGO have to say about this? Maybe we will need to ask this an ambassador?! Share this post Link to post Share on other sites
Duq Posted January 3, 2012 My comments are based on what I was told by one of the developers at Lego... Share this post Link to post Share on other sites
skaako Posted January 4, 2012 I manged to do it with a Technic Axle Pin by cutting the pin in half and fitting inside a PF Train motor. The result is quite good and with the new PF motors it is much more easily installed as the motors can be disassembled without causing permanent damage to the casing.. I really like the look with the PF motors as all the wheels match nicely.. I have also run a few 9V motors with this modification done for many years without any noticeable wear. In order for the pin to rotate smoothly cut in half and then file back until it can turn freely.. i add a small drop of silicone to keep it lubricated. Looks better with the end painted black too :) Oversized images removed by moderator. Please see site guidelines re. image posting. (Sorry for that.. i have re-sized the images) thanks -TB Share this post Link to post Share on other sites
mikka says Posted January 4, 2012 Thats a very convincing mod :D hows the casing standing up to the wear of the spinning of the wheel, i'd be particularaly interested to know as im thinking of making a 12v stlye train with PF in it. 7755...i think... cheers :) Share this post Link to post Share on other sites
bricks n bolts Posted January 4, 2012 (edited) Looks better with the end painted black too :) Nice solution, don't they come in black anyway? ( http://www.bricklink.com/catalogItem.asp?P=43093 and http://www.bricklink.com/catalogItem.asp?P=3749 ) Edited January 4, 2012 by bricks n bolts Share this post Link to post Share on other sites
skaako Posted January 4, 2012 Nice solution, don't they come in black anyway? ( http://www.bricklink...tem.asp?P=43093 and http://www.bricklink...Item.asp?P=3749 ) Cool thats much better than painting..i'll have to get hold of some of those.. Thanks I did this mod to some of my 9V motors a few years ago and they r still running alright.. one of them i changed back to 4 wheels but the other one is still fine with 6 wheels. Share this post Link to post Share on other sites
JopieK Posted January 4, 2012 this is a really cool mod!!! Share this post Link to post Share on other sites
LEGO Train 12 Volts Posted January 4, 2012 (edited) Your railroad-track modification on brickshelf are totally cool!!! The three way swith point is my favorite! Edited January 4, 2012 by LEGO Train 12 Volts Share this post Link to post Share on other sites
skaako Posted January 5, 2012 (edited) this is a really cool mod!!! Your railroad-track modification on brickshelf are totally cool!!! The three way swith point is my favorite! Thanks for the comments guys!! ..I'll add some photo's of inside the motor too....Here Edited January 5, 2012 by skaako Share this post Link to post Share on other sites
Konrad Posted January 25, 2012 Thanks for the comments guys!! ..I'll add some photo's of inside the motor too....Here I did the exact same thing!!! great idea, now we need to figure out a way to make side pushrods 12v style and well, 12v will lose all its wonder :P Share this post Link to post Share on other sites
Shupp Posted January 25, 2012 (edited) That's a nice mod. I built a 3-axle truck out of one of those motors, once. (On the tender. Sorry I don't have a better picture of it.) Prussian P 3 Locomotive 2-4-0 by Shuppiluliumas, on Flickr It's just held in with a 2L axle and and the modified plate. This obviously won't work for a 12v motor lookalike, but could be useful for other applications. Edited January 25, 2012 by Shupp Share this post Link to post Share on other sites
