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Since this is my first post I'll start by saying I've been a life-long fan of lego technic. I'm 29, and I recently got back into the hobby and I'm building a 16 unimog-wheel scale mobile construction crane with at least a 4, and probably 5 section telescopic boom (but it will only go straight up and down. A boom that large made of lego can't work in cantilever. . . at least not work well. Anyway, I have I think 22 m motors from various sets, and I've started testing the motors. Turns out I got a bad motor. I opened it up and the problem is an internal short in the capacitor. If I squeeze it or apply any pressure to it it shorts and the motor stops spinning (and the LED on the battery pack turns off indicating high-current draw protection). I'm handy with a soldering iron and I have small spare capacitors laying around, so I thought about replacing it. I also thought about trying to get a replacement from Lego (either through the internet or at a store). I was curious as to the RMA process through lego. Secondly, I thought about not replacing the capacitor at all, and just taking it out of the circuit. This made me wonder if this would give me IR V2 comparability if I did this to all of my m motors. I understand the importance of a capacitor for noise reduction, which doesn't seem important here since we're using infrared and not RF. I read this post on TechnicBricks a while ago: "The raw motor currently used in the LPF Medium motor internally contains a relatively large capacitor (1 uF) across each of the 3 motor coils. This is done by the motor manufacturer for noise reduction. We knew that this would be an issue with the new CMOS motor driver (DRV8833). Since it can source a very high inrush current the over current protection will kick in sooner (typically after 2,25 us with a current exceeding 3,3 A). At start up the motor driver will first charge the input capacitance. With 2 or more LPF Medium motors at the same output this can trigger the over current protection. It will repeatedly try to start the motors and you will only hear a singing noise. For many reasons we have been searching for a higher quality solution for the LPF Medium motor and we now have an approved new raw motor. It has better quality commutation and only 1nF across the terminal. An updated LPF Medium motor will be released during 2013." All of my M motors are definitely not the new versions, and I'm not sure I'll ever buy any more M motors (because I have enough) and the L motor is about to be purchasable by itself. I guess my question is regarding the above quote is are there 3 additional capacitors inside the motor itself? The capacitor that I can see when I remove the shroud is definitely in-line with the main power wires. It does not cross the poles. If I remove that capacitor will it negatively affect performance, and will it give me IF V2 compatibility? While I'm at it, here's a picture of my build station. And more random pictures of my build so far. Really just prototyping, although the wheel carrier design is finalized so I went ahead and built all 16 of them. http://sammorganphoto.smugmug.com/gallery/28096733_2sPxG6#!i=2374027084&k=HnHn3Pm
