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LEGO Functions Train Motor (8866)

  • $10.99
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Product Description

CHOKING HAZARD - Small parts. Not for children under 3 yrs.

Send your train roaring down the track! Add the Train Motor to your train engine together with the required Power Functions parts, layout your tracks, and your train is ready to roll!

To be able to understand why LEGO has been successful for so long, just look to the name. LEGO originally got its name from founder Ole Kirk Christiansen who combed the Danish words "Leg Got" which means "play well". He later realized that LEGO in Latin translates to "I put together. The LEGO set became a standard of creative play for children worldwide, unlocking the creativity to build vehicles, buildings, cities and more. Historians point to the invention of the wheel as a major turning point in world history. The invention of the LEGO wheel had the same monumental effect in the history of LEGO, making it possible to create cars, trucks and eventually the LEGO train building set that is one of the most successful LEGO sets of all time. LEGO currently produces about 20 billion LEGO bricks a year and has sold over 400 billion LEGOs in their history -- enough for every person on the planet to have over 60 LEGOs each!

Additional Info





0.1 pounds

3.8 x 2.1 x 1.4

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Average Customer Rating:

by PowerReviews
LEGO Functions Train Motor (8866)

(based on 17 reviews)

Ratings Distribution

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of respondents would recommend this to a friend.

Reviewed by 17 customers

Displaying reviews 1-10

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(6 of 8 customers found this review helpful)


does not work with power function,

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By AFOL dc area

from wash dc

See all my reviews

Comments about LEGO Functions Train Motor (8866):

This is train motor does not work with newer train sets(e.g. red cargo train) power function battery packs - it uses the older four stud 9vdc connector. It requires an older four stud 9vdc connector wire and older 9vdc battery pack to work. This train motor requires a strong current so it will not work with less than 9vdc ( e.g. two dacta solar panels in full sun will not work). The only part that isnot obsolete in this set are the axle and train rail wheels assembly which still can be used with the newer train sets.

  • Was this a gift?:
  • No

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(11 of 16 customers found this review helpful)


Great little motor

By Suspet

from Humlebaek

Comments about LEGO Functions Train Motor (8866):

Made for the RC trains. One advantage to this motor compared to the 88002, is that the wire can easily be replaced if damaged. You can use this motor as an auxillary motor for 9volt motors, using a technic/RC wire to connect them. Unfortunately this motor has less pulling power than the 88002. It's a shame the the bogie sides are not included, as they were on 9volt motors.

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(3 of 3 customers found this review helpful)


This is great but it ...

By Moore202

from Apopka

Comments about LEGO Functions Train Motor (8866):

This is great but it doesn't have enough tork and it will have slip and stalls a-lot but i still like it i even take the train wheels off and use it with my power functions sets.

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(4 of 8 customers found this review helpful)


All most Great

By Smeg

from Wellington

Comments about LEGO Functions Train Motor (8866):

This motor is great but when I used it on my LEGO train I biult and at first it work fine. But now, (about three days ago) it stopped moving and when it came to the switch tracks, it stopped! I don't know why, and tried every thing including changing th IR resever to a new one and replacing the batteryes in th battery box but nothing helped. Mayby not the best purchase-but pretty good!

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(50 of 56 customers found this review helpful)


Product not as advertised

By Tearloch33

from Colchester

Comments about LEGO Functions Train Motor (8866):

I purchased this product to use on a LEGO GP-38 BNSF train in an effort to convert it to Power Functions. The motor itself is a fine product, and upon initial review, it looks just like the Power Function train motor that comes with the Cargo Train #7939 train set, except for the electrical connection. What I found out is that this motor is actually different than the motor from #7939 in several ways, including having less power and torque, as well as using more current (from LEGO customer service). The other issue is that when you add on the Power Function extension cable #8886, it becomes useless since the brick that connects the extenion cable to the motor (that brick has 2 studs and the Power Function electrical connection blocks on top of it) extends above the level of the boogie plate, meaning that it will catch on the underside of the standard LEGO train base preventing normal rotation during turns and causing derailments. The train motor that comes from the #7939 set (which has an inbedded cord instead of electrical connection studs, thus no extension cable required) is far superior, and LEGO should make it available for purchase, or atleast modify the motor end of the extension cable #8886 to remove the studs and electrical connectors (like a flat tile) since in its intended use as a train motor, there is no need for the studs or electrical connections. I am very dissappointed in this product and the support I have recieved from LEGO so far. I hope this review helps other LEGO train enthusiasts, as well as LEGO customer service and sales teams on how they are advertising their product or what products they sell.

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(2 of 16 customers found this review helpful)


Miss Labeled Item

By Shelie

from Houston, TX

About Me First Time Parent

Verified Buyer



    • Not for young children

    Best Uses

    • Older Children

    Comments about LEGO Functions Train Motor (8866):

    This Train Motor is for ages 7 and above. I bought it under the impression that it would work with the Duplo trains and it will not. Website has it listed for children younger than 7 years old and that is incorrect according to the package.

    • Was this a gift?:
    • Yes

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    (12 of 13 customers found this review helpful)


    Simply not good enough

    By MisterMiniroll

    from North West, England

    Comments about LEGO Functions Train Motor (8866):

    I can only agree with the previous reviewer - Torque is very much the number one problem with this motor. For many of the more mature LEGO audience members, we no doubt grew up with 9V systems which meant that the wheels and track, both lined with metal, safely created a circuit that would allow you to control the train from a sturdy control deck and mains electrical output. Not only was the power produced from this set-up better, but it meant that the 9V motor itself was the only appliance within the Train. With these new 'Power Function's products, you are required to have a large battery pack as well as this motor in the Train, so not only does it remove detail/space from the locomotive (see Emerald Night), but it increases weight. Its saddening that LEGO no longer support the huge fan-base that still believe in the 9V set-up, but like others, I will continue to forgo the 'Power Functions' in favour of the former technology. Should LEGO re-instate 9V products, then I'm almost certain they wouldn't regret it.

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    (4 of 5 customers found this review helpful)


    Great If Used Correctly

    By Turner

    from Lindon, UT

    Comments about LEGO Functions Train Motor (8866):

    This is great if you are trying to make a realistic electric or deisel locomotive. This motor is also included in the new Cargo Train and Passenger Train. Its pulling power makes me a bit sad compared to the Emerald Night. The motor has a ton of horsepower, but hardly any torque to match. One basic rule that Lego seemed to ignore is that your torque should at least match your horseower to create the ideal motor. Lego could have solved this by adding small rubber bands similiar to the Emerald Night. After all, the rubber bands are what gives the Emerald Night so much power. For example, with the Passenger Train, if you run the motor with just the locomotive, on setting 7 it will tip over on turns. Even adding the middle passenger car still makes it tip over. Lego solved this extra horsepower by having the last car use a higher friction arrangement on the front bogie by spacing the wheels out more. This way, the flangs grind the rails a bit more, thus slowing the train down. It also makes the train more symmetrical, because it copys the wheel spacing on the locomotive. So that's how lego did it. However, this arrangement can backfire if you want more cars. For longer trains with 4+ cars, I would suggest putting the wheels side by side for less flang friction WITHOUT a high friction wheel arrangement For trains with 2-3 cars, I would suggest copying the Passenger Train wheel arrangement. But remember: only the last car needs only ONE high friction arrangement. Overall, this is a great power functions set, but for maximum enjoyment, follow my advice above.

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    (6 of 6 customers found this review helpful)


    Good for fast trains

    By mhoeij

    from Tallahassee, FL

    Comments about LEGO Functions Train Motor (8866):

    Some people have written that this motor is not as strong (less traction perhaps? as the previous 9V motor. I found that this motor can pull just as much as the previous 9V motor. I currently use it in a 5-car train (I bought two 7897 sets to build one 5-car train and one 1-car train). This motor can pull that 5-car train just as fast as the old 9V motor can (i.e. it derails on the highest speed setting, which is not a great thing because the track is on tables in the garage, and the floor is concrete, so a derailment means a hard landing, and searching for pieces all over the garage). The biggest problem is running trains at lower speeds. Others blamed the motor, but I think that the problem might not be with this motor, the problem might be the electrical controller used in the 7897 train. Speed settings 1 and 2 don't move the train, and it has a hard time in setting 3 as well. Setting 7 causes the train to fall on the floor, so I can really only use settings 4, 5, 6. Basically, what now is setting 3, that should have been the lowest setting.

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    (4 of 4 customers found this review helpful)


    New motors more adaptable

    By RRguy

    from Whitehall, MI

    Comments about LEGO Functions Train Motor (8866):

    I bought this item before the Emerald Night was given to me and won't buy any more again. I have a large number of the old style track from the seventies, the kind that the rails aren't molded to the ties. With the new motors, I can make any width of engine I want because I can make any width track I want. I can make narrow gauge trains now and overhead people movers. The new motors are so much more versatile I won't ever need to use this type of motor again. You only need the wheels and you can buy them separately.

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