Installed Corn Head Grease in my new Luna Z1 Bafang Ultra Mag

[Fast n' Furious]

Certainly !!!

 

[AvalancheRun]

Certainly !!!

So, I have a brand new H720 Bafang motor with pronounced gear noise. All of the bikes with this motor sound the same. Why wouldn't the factory add the proper grease if it reduces noise so much?

Just trying to see if there are any downsides before popping it open.

 

[Fast n' Furious]

It wouldn't. If it's a universal flaw why bother ? You're doomed.
If your gears are noisy 'it [might] reduces noise so much' temporarily.
Inherent poor design and bad gears meshing will not change.
A Creosote based lube might really help, but the noise is gears running on edges - singing 'help me, help me'.
Sharp surfaces cut right through grease. They want to be flat.
Low Powered motor's gears can take that. 100Nm and up not so much, but once they know riders work with it, avoid sudden high torque input, whatever.
The M620 now has a new steel gear-set - more teeth. That's how you make 'quieter'.
Not corn-combine grease.

 

[PCeBiker]

So, I have a brand new H720 Bafang motor,..

I had to Google that,..

Bafang Unveils the New H720 Rear Hub Motor eDrive with Automatic Dual-speed Shifting – eBikes Int'l

ebikes-international.com

Holy Crap !!

I didn't know that there was such a beast ?!!
I want one !!

It looks like it only accepts a single sprocket though, but I'm fine with that.
I don't pedal anyway.
I'll just pick a low gear to use if I'm forced to pedal.

@AvalancheRun,..
Does your cadence shift with the gear change?
Are you effectively pedaling like a two-speed bicycle with automatic shifting?




I'm gunna grease my motor the day it arrives.
If it has a universal flaw, then doing what I can to postpone the inevitable just makes sense to me.

Plus, I wanna take it apart to see how it works.
It looks like the shift points can be adjusted.

Does anyone know if it is mechanical shifting using centrifugal force, or if it's electrical with solenoids and sensors and such?

Can I plug it into my KT controller, like any other hub motor, or is there an additional control wire to operate the "automatic integrated derailleur" ?

 

[Tom@WashDC]

I had to Google that,..


View attachment 189214

Bafang Unveils the New H720 Rear Hub Motor eDrive with Automatic Dual-speed Shifting – eBikes Int'l

ebikes-international.com

Holy Crap !!

I didn't know that there was such a beast ?!!
I want one !!

It looks like it only accepts a single sprocket though, but I'm fine with that.
I don't pedal anyway.
I'll just pick a low gear to use if I'm forced to pedal.

@AvalancheRun,..
Does your cadence shift with the gear change?
Are you effectively pedaling like a two-speed bicycle with automatic shifting?




I'm gunna grease my motor the day it arrives.
If it has a universal flaw, then doing what I can to postpone the inevitable just makes sense to me.

Plus, I wanna take it apart to see how it works.
It looks like the shift points can be adjusted.

Does anyone know if it is mechanical shifting using centrifugal force, or if it's electrical with solenoids and sensors and such?

Can I plug it into my KT controller, like any other hub motor, or is there an additional control wire to operate the "automatic integrated derailleur" ?

It should work om the KT Controller fine.

 

[PCeBiker]

It should work om the KT Controller fine.

Awesome !!!
How do I get one?
All I can find is reference to them without any links,, except the AliExpress link that I don't trust at all.

There's no technical data or pictures provided by the seller,..

I just found this on AliExpress:
C$520.76 | Bafang Gear Hub 5 Speed Auto-Shift Gear Hub G500A RG A510.D For Bafang Mid Motor Kits

https://a.aliexpress.com/_mPJ7sZN

And is it mechanical shifting or is it full of computer chips and programming?

What about the H720 2-speed for a fat bike?
I can't find anywhere to buy it?

@AvalancheRun did you buy the motor or an e-bike with that motor?

A two-speed is good enough for me, but the gear ratios are 1:1 and 1:1.3* and my geared hub motor gas a 5:1 gear reduction.

Does the 1:1 and 1:3* gear ratio on top of the normal 5:1 gear ratio, or does the wheel turn four to five times slower than my hub motor?

 

[PCeBiker]

It should work om the KT Controller fine.

I found acouple of motor connectors for what I think is at least one of the Bafang IGH hub motors,.

I think this one has a 9-pin motor cable, and I'm hoping
3 phase wires
3 hal sensor wires for each phase
1 hal sensor wire for speed sensor
+ and - 5VDC wires to power the hal sensors

I don't know about the red connector but I figure the extra two wires are for a temperature sensor and I guess some kind of digital crap that I want to avoid.

BUT, the same motor is available with either connector, so I'm thinking that the gears and shifting are mechanically operated with cintipedal force (or do I mean centrifugal?)



I worked on a ½ horse furnace fan motor that was overheating.

It turned out that it was a "2-speed" motor of sorts that had a centrugal activated switch that was supposed to shut off a secondary set of windings after the motor got up to running RPM.
The switch was sticking and wouldn't shut off.
It just needed a cleaning and a dab of grease.

 

[tomjasz]

How do I get one?

I'd first call or email Anna at Greenbikekit. Remember Aliexpress is a conglomeration of Chinese resellers. Sales rules are better, just due diligence as it's till often a Wild West atmosphere, BUT there are reliable sources. Patience. Especially during holiday season in China.

Consider which vendor has parts!

bafang RM G062 1000W fatbike/snowbike motor with strong torque-greenbikekit.com BBS, ebike batteries, Bafang M620, Bafang M600, Bafang M500, Bafang M510, KT controller with display-GreenBikeKit.com

Bafang RM G062 fat motors for electric snowbike with strong torque, high power 48V 1000W.

www.greenbikekit.com

 

[PCeBiker]

I'd first call or email Anna at Greenbikekit.

That's a good idea.
It sounds like the H720 is kind of a rare bird?

I checked out Grin as well, and they sell Bafang motors, so I might be able to get a complete wheel built through them?

They have a professional wheel builder that would know about stringing an H720 into a 27.5" rim.

I went through an order process for a G06 motor, and they didn't offer a 27.5" rim.
I don't know if that's because people normally put fat motors on 26" fat rims, or if there aren't any 27.5" rims that fit properly?
Voltbike did it, but it really doesn't look right to me, although the wheel has been fine.

Grin is Canadian too, so I won't have to worry about the tariff war crap.

I'm in no rush so I'll try to find out everything I can about the H720 in the meanwhile.

The 1:1 and 1.3 gear ratios don't make sense to me?
It doesn't look like a direct drive motor?

I found out that the 3 and 5 speed hubs are just geared hubs, not geared hub motors.

 

[PCeBiker]

I forgot that this was a head grease thread.

I couldn't decide whether to buy the ten dollar corn head or the fifty dollar red stuff, so I bought both.

Then I greased my Bafang RM G06.500.D geared hub motor.

I've got plenty left over for both my combine and airplane.

I couldn't find the Mobile 28 anywhere in Canada except at aircraft hobby stores, so it did cost me $50.


Then I decided to take my motor apart and grease it up with the red stuff.

I thought I'd picture bomb the thread with greasy motor pictures,..


I found out that the motor cable Works Great to channel water into the motor, so I had previously plugged the axle hole with silicone.

Rusty turd,..

The white lithium grease got flung off in clumps everywhere,..

This is where the flying clumps get tossed inside the motor,..

The magic key fell out when I pulled the gear assembly off,..

I studied where the grease was flying so I could figure out where to safely put the new grease.

Your standard skateboard bearing, but my board bearings are better quality.
The board bearings first improvement to the 608Z bearing was the ABEC 1 and I think it's up to ABEC 9 or something now?

The 608Z is a standard bearing though, and there's probably different levels of quality with the same bearing code.
The ABEC bearings are kinda skateboard specific.

No grease under the nylon gears,..

The larger axle bearing and one of six speed magnets,..

The axle seal did its job and kept all the crap out of the motor.
It was a proper lipped seal with a tiny stainless steel coil spring under the lip keeping the seal tight against the axle.

I remembered reading this thread about a year ago, and knew to remove all the old grease before putting in the Mobil 28, but it was a huge PITA.

The old grease was as thick and sticky as plasticine and stuck in between the gear teeth so I spent almost 2 hours scraping it out with popsicle sticks and toothpicks.
I didn't want to use solvent because I didn't want to get it into the bearings.

 

[PCeBiker]

Closeup of the magic key,..

There was a shim washer on the axle that I didn't want to lose track of, so I zip tied it in place.

The PC board with the four Hal sensors,..
Three monitoring the the phases of the motor.
H4 monitors the speed magnets.

The little capacitors are sealed up nicely,..

PS,.. when the KT display asks for "Poles In Motor", they are asking about the number of speed magnets, not the number of magnets of the motor itself.

I tried to count the damn teeth more than half a dozen times, and just kept losing track, so I took a picture and drew on it to count the teeth.

I started loading in the grease, spinning it up, then removing the clumps.

Any grease below the gear teeth is fine and shouldn't migrate anywhere it shouldn't go, so I put some on and below the teeth.

This is the area if concern,..

I didn't want any grease flying inside the motor.
If any grease gets under the internal motor magnets, it will drag on the spinning drum that has a micrometer of clearance between the drum spinning past it.
And the other side of the spinning drum has a micrometer of clearance between the outer motor casing above the teeth.

I noticed that a tiny speck of grease got flung inside the motor, onto the spinning drum and made a black mark on the drum.
I'm thinking that it either reacted with the metal, or just got hot and burned it?
The grease in the gear teeth was also black, and that's where the grease was also the driest and stickiest.

You definitely don't want any grease on any of the spinning surfaces of the drum or the adjacent surface.

That's where I stopped taking pictures.

I packed in grease, put the motor together, spun it up, took it apart, and removed the clumps over half a dozen times, then I added a thin layer of grease everywhere that was safe to do so figuring that it would prevent rust.
And any dust that might find its way inside the motor would stick to it.

Then I oiled the coils and circuit board with special oil, cleaned up and greased my axle seals, then realized that my motor had been apart for more than a month, so I put the damn thing back together before I forgot how it goes back together.

Hopefully I will have my e-bike ready for the road before the end of next riding season.

 

[tomjasz]

I thought I'd picture bomb the thread with greasy motor pictures,..

Nice! Thanks! Someone will be able to use those photos. I didn't read the entire thread but if the models versions and part numbers are in the text it'll pop up in a search.

 

[PCeBiker]

I didn't read the entire thread ,..

Ahh Crap !! Neither did I !!

I didn't know SCH100 was a better choice than Mobile 28 ?
And it's only a buck and a half more than the Mobile 28, from the same Airplane hobby store.

I'm not spending another fiddy bucks on fancy grease.

I've decided to buy a new motor instead.





Nice! Thanks! Someone will be able to use those photos. I didn't read the entire thread but if the models versions and part numbers are in the text it'll pop up in a search.


I added "Then I greased my Bafang RM G06.500.D geared hub motor."
to my post.


I guess I should start a new thread?
This thread is about a Luna mid-drive.

I could call it,..

"I highjacked Tom's corn-based mid-thread and turned it into a synthetic clay-based hub-thread"

Then just post a link to this thread.

 

[tomjasz]

I've decided to buy a new motor instead.

Too funny, but looking through my boxes I've done just that too many times!

 

[tomjasz]

I didn't know SCH100 was a better choice than Mobile 28 ?

You can get into a myriad if differing opinions. Me? I went with what an engineer with Mobile Aviation suggested and used up my 28, and replaced it with SCH100. I'm wondering though if we're not just splitting hairs. Regardless I've always followed my own research.