My 500W geared hub motor has close to 4000 miles on it, and last fall it had been getting louder and louder. Even at a steady 15mph on the level you could hear a whine, and under load on a steep hill the noise became a loud howl, to the point that people would turn to see what it was. It was actually embarrassing!

I planned on pulling it apart during the winter but forgot about it until we finally got a few "spring" days and I was quickly reminded it needed help. Today was wet and cold - a non-riding day - so I pulled it apart. I found a lot of old grease in it, but it all worked its way out of the gears until all the teeth were dry. Teeth looked good and all seemed to mesh well, so I just cleaned out the old grease and liberally re-lubed with white lithium grease. It is now quiet as new when running free on the stand - still raining so maybe tomorrow I can give it a full test ride.

It was a relatively easy job, and I was able to pull it apart with it still laced in the wheel. I had never seen any recommended service interval for geared motors, but this will now become part of my regular winter down-time maintenance.

Who are you genius!

Smart! It feels real good when you do something like that and it fixes your problem. Congrats. Let us know what happens in the "real world" riding.

What brand of motor do you have? My Bafang is making more noise and was considering regreasing it.

Motor is from eBikeling 500W, 36V conversion kit. Private labeled with their logo, don't know actual manufacturer, obviously some China product. I did contact them about obtaining a set of gears for it just in case, but they carry only complete wheel assemblies, no separate motors or replacement motor parts for them. However they are good people to work with and are contacting the manufacturer for me, then will let me know what is available.. With the virus situation I assume it will be a while before we hear much from Wuhan


It was a very simple process as this motor has separate cover plates so I did not have to unlace the spokes to pull it apart. I was able to leave the motor body in the wheel and just pull the internal assembly out. From pictures on the web it appears that many Bafang motors have the spokes attached to the covers making that more complex, involving a wheel rebuild. There are a couple of YouTube videos showing how to pull a Bafang apart that might be helpful. Fortunately it appears that Bafang gears are readily available if needed.

I pulled my Bafang hub apart yesterday and the gears look fine. I was able to clean old the old white grease and everything looks good inside. I have some white lithium grease on order to lube it up and reseal it. I'll let you know if that solves the noise issue.

The only lithium grease I had on hand was an aerosol can product. It initially cut the noise back, but after about 250 miles the motor is gradually getting a bit louder. Gears looked good when I had it apart, meshed fine with no play, but I think the spray can product may not heavy enough. Probably works fine for my garage door operator or light duty applications. I will monitor it and have ordered a heavier #2 synthetic gear lube to have on hand if needed.

I did note that a couple of Utube posters recommended using a heavier synthetic grease in Bafang mid-drive motors in place of white lithium. Others suggest a special Mobil synthetic aviation lube.. But anybody can be an expert on Utube!

There is a special brand of Mobil grease for the geared motors. Anything else will be trouble. Check on endless sphere for the right type. Sorry I dont recall the number offhand.

-SP