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Electric Scooter and Bike Motor Rebuilding

OK... I started in this group looking for ideas to get a used crazy cart running.  I started doing some meter testing and eventually I ended up checking the motor.  I opened the motor to test with the meter.  

1st question and if I don't get an answer here the rest of the trouble shooting questions don't matter.  

When I took the motor apart to get to the electrical connections the spring loaded magnets popped out.  How the heck to you compress those springs and magnets to close the motor back up?  Too many hands in a small spaced needed.  There has to a trick to it.  I'm handy but, not an electrical guy.  Thanks.

One way I know of to get the electric motor back together is to make four brush retaining tools out of wire. Large paper clips, bailing wire, coat hanger wire, or bare copper electrical wire that is thick enough to do the job should work good to make these tools. The four brush retainer tools will hold the four brushes back while the motor is reassembled and can then be turned 90 degrees to release the brushes and remove the tools before fully closing the motor case back together. Here is a drawing showing the general shape to bend the wire to make these tools. The brush retaining tool is drawn in black.

Please let us know if you have any questions.

I just remembered another method which involves retaining the brushes with a piece of straight wire that goes through a small hole near the end of the brush holder. I have seen this method used on a few electric motors before so the hole might already be there from when the motor was first built. Straightened out paper clips usually work great as the wires for this method. Here is your photo marked up with directions for this brush retaining method.

I did a little more research into this and found out that most electric scooter and bicycle motors such as MY1016, MY1018 and MY1020 models should already have one hole drilled near the end of their brush holders that a straightened out paper clip will fit into to hold the brushes in place when reassembling the motor. Here is a photo of a MY1016 motor's brush holders showing the factory drilled holes.

Yes-  that just about sums up my next plan of attack.  My concern was that the brush holders are deeply recessed in the end housing mounted on a plate and there is only  a 1/4 in opening between the motor casing when trying to re-attach.  I was even considering drilling my holes perpendicular to the brush holders by drilling thru the face of the housing and inserting the pins in that fashion- allowing for clearance of the armature.  Ideally would be some sort of cylindrical wound piece of plastic that could be inserted horizontally to hold all four brushes in place while the case is attached.  Once in place, the coil could be " unwound"  by pulling on the loose end and having it snap back into position, or even a single-use coil would work as well. 

My problem arose when I tried using pieces of matchbook cover as wedges to hold the brushes in place.  They worked TOO well and the brushes remained stuck, even after re-assembly.  

Electric motor rebuilding is very finicky work even with the proper techniques and tools. It takes good mechanical skills and a steady hand to rebuild most electric motors. It is always worth it though because if you can finish the job then when you are done you will have so much more pride in the hearing the motor run than you did before you started working on it.

Happy Father's  Day to all you Dad's, Uncles, Grandfathers and future Fathers.   Here is the most recent update.   I was able to successfully drill through the brass Brush holders at a slightly oblique angle due to the aluminum housing.  Note to self:  Be extra carefull when drilling thru the Carbon brushes because they are MUCH softer and they are brittle.  Find a source for a set of replacement brushes.     

The question I now have is:  What could I have done that would cause the Motor- which previously ran Forwards to Now run Backwards?  Is it possible to flip-flop the gears in a Currie Direct drive assembly that would reverse the direction of the driving axle?  The only other item that was replaced was the battery pak and I have verified that it has the correct polarity.   I know that I can change the direction of the motor simply by switching the Blue and Green Leads on the speed controller but it would still be nice to know what I did that caused this.   Everything ran fine and normal rotation prior to changing the battery pak and disassembilng the jack-shaft assembly.   Does anyone have the Currie factory specification for the motor rotation direction?    

I do not believe that it is possible to flip flop the gears in the Currie direct drive gear reduction assembly so I am leaning more towards the motor spinning backwards.

I checked and could not find any Currie factory specification for the motor rotation direction.

If the motor is spinning backwards after being taken apart and reassembled then chances are that the end plate was put back on the case a little out of alignment from where is used to be. If the end plate is even a little out of alignment that could cause the motor to spin backwards. There are usually alignment tabs or marks on the end plate and case that indicate how to align them.

Please let us know how it goes.

I was very careful about realignment and indexing the brush plate to the original location.   It should be a simple matter of swapping the motor power leads coming out of the controller to reverse the polarity again in order to have the motor spinning in the "right"  direction.   It is just befuddling that it happened.   I read your post where you stated that you had purchased all of Currie's remaining stock- including a handful of these 1000 watt direct drive jackshaft assemblies.  You are or were awaiting arrival of the Rear rim and Tire assembly.    Do you know if it is still possible to obtain ONLY the XYD-14 1000 watt motor minus the gear/axle housing?  I know that they still offer the chain driven version with a countershaft sprocket attached, but the jackshaft version sports a helical-cut pinion gear and I do not no how it is attached to the armature shaft of the motor.    I have seen some videos of a chain-driven scooter that was converted from direct drive, but it required fabrication of all new motor mounts and the addition of a rear sprocket /freewheel and new bearing supports. 


That is bewildering how the motor's shaft switched directions after reassembling it, especially since you were careful to realign the brush plate in the same position. I never knew until now that those motors were so sensitive.

Unfortunately we do not have those motors available individually. We only have them available as an assembly of the motor with gearbox and axle.

I do have a couple of questions regarding some Of your retail products.  I have ordered a 48 Volt speed controller and it uses Molex connectors that are not the same as the ones on the Currie ( Yi-Yun ) controller.   Specifically, the molded red and black flat battery pak connectors that you sell as item CNX-2PX2.  I have seen these made by Hopkins or Spectro but they are not exact copies of the ones you sell.   You also have the two pin Molex connectors CNX-50.    What I am trying to accomplish is to create an " adapter" that will allow the two to be connected without cutting and splicing wires.  While I am happy to buy them from you, I was wondering if you might know of a local company that sources these items ?

The molded flat battery pack connectors with red and black wires like our CNX-2PX2 are standard trailer lighting connectors which may be available at local trailer or auto parts stores, however they are usually not available locally with thick gauge wires as needed for electric scooter motors.

The two pin connectors such as our CNX-50 are not a very common connector and I do not think that they would be available locally. These are not Molex connectors and they are based off of a Japanese vehicle electrical connector.

We have the parts to make the adapter that you need. The CNX-50 connector terminals require a specialized crimping tool such as our CRM-85, or the wiring insulation crimping tabs can be snipped off and the wires can be soldered onto the terminals instead of crimped. When we make adapters we go the extra mile and crimp the wire onto the terminal first, and then solder it to the terminal after it has been crimped.

We charge one dollar per terminal connection when making adapters so it would only cost two dollars more to have us make the adapter compared to buying the parts from us and making it yourself. If you are interested in this service then please let us know.

Please let us know if you have any questions.

I do have more questions-  Sorry.  The Currie Ezip 36 volt charger I have is a four pin model, however  it would appear that only three of the lugs are in use- Red- Pos, Black- Neg. and another black to ground.  The fourth pin is not in use. Would it be more beneficial to revert back to a three pin charging port and Three pin XLR connector on the charger, or was this an intentional move by Currie?   I did read about a discontinued " Charge Inhibitor" circuit but I was under the impression this was incorporated as a safety feature so the motor could not be accidentally activated while the charger was connected ?  I would prefer to charge my battery packs "on the bench"  rather than while installed on the scoot.  It just seems easier to revert back to the three-pin configuration under the circumstances.  Unless there is an " advantage" to the four pin XLR plug? 

Currie used four pin charger plugs and ports on their later model 36 Volt scooters so that their 24 volt chargers with three pin charger plugs could not be accidentally plugged into a 36 Volt scooter, and visa versa.

Other than this there is no reason that a scooter with a four pin charger plug and port could not be converted to have a three pin charger plug and port, as the fourth pin is not used.

The charge inhibitor circuit was introduced as s safety feature to prevent the scooter from being operated when the battery charger was plugged into it.

Please let us know if you have any questions.

This is a question" Where can I Get Brushes For the Motor on a razor ecosmart metro electric scooter ?

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