LEGO bb53 How to fix 12V grinder for railway motor type 1 - Flagsoft
BrickLink - Part bb0012vb : LEGO Electric, Train Motor 12V with Wheels Type II with 3 Round Contact Holes [Electric, Train] - BrickLink Reference Catalog
trains - What prevents a 12V motor, when pushed by hand, from providing DC electric out? - Bricks
BrickLink - Set 7865-1 : LEGO 12V Motor [Train:Supplemental:12V] - BrickLink Reference Catalog
LEGO 7865 12v Train Motor Set Parts Inventory and Instructions - LEGO Reference Guide
Trains | Supplemental / 12V | Brickset: LEGO set guide and database