Help finding a solution to Bafang gear stripping

DON'T PUT OIL IN A BAFANG. The windings and sensor wires etc are tied with a paper-like string. I'm sure these will just disintegrate once saturated with oil. Then the wrong kind of bump, a wire moves and starts rubbing on a moving part and you're done. I love the idea of perfectly lubricating and wearing in the gears properly, just not with this motor. I think what's called for here is gentle run-in, clean and regrease.

John
 
John in CR said:
DON'T PUT OIL IN A BAFANG.... I think what's called for here is gentle run-in, clean and regrease.

That's the plan. The Bafang is not well sealed, it's also got no sealing between the gear reduction components and the motor itself.

I don't know how "gentle" I can force myself to be :twisted: :oops: but I will run it at 80V for a bit then open it up, clean out the moly grease and repack.

I think the steel is soft on the planetary gears and will be the sacrificial part of the system.
 
I just installed my new metal gear in my rear Bafang. Just 1-metal gear (from Keywin) as I suspect 1 will be enough.

Did some great on-road testing today (at 72V and 30A) and as expected the Bafang with 1-Metal and 2-Nylon did great. :D

Noise was minimal and there is actually a sweet spot over 20 MPH where the motor is very quite.
Bafang ran like a champ with 1-Metal gear. I think the days of peanut butter are OVER! 8)

voicecoils said:
My circlips are starting to seriously bite the dust but I will look for some fresh ones soon.
btw. Just ask Keywin to send you a bunch. I have plenty here. The ring-clip tool I picked up from a local auto store makes life sooo much easier too.

Gear_Clips_n_Tool.jpg
 
Knuckles said:
voicecoils said:
My circlips are starting to seriously bite the dust but I will look for some fresh ones soon.
btw. Just ask Keywin to send you a bunch. I have plenty here. The ring-clip tool I picked up from a local auto store makes life sooo much easier too.

Cool, I have access to a circlip tool fortunately. I'll see if Keywin can send me some. Were some of your gears poorly cut too?
 
voicecoils said:
Were some of your gears poorly cut too?
Keywin only sent me one metal gear (I only wanted one) and it looked fine to me. I did check the mesh with a virgin Nylon gear and I did notice that the metal tooth penetration was slightly less than the Nylon tooth penetration. Is that what you mean?

All in all it looked fine to me.

But I will try to destroy this rear Bafang motor if I can.

But GOSH! I live on FLAT Long Island. No monster hills to climb!

But I have also been running the rear PUMA w/ 1-Metal gear.
(I run every motor I have at 72V btw)

The Bafang has good torque. The PUMA has INSANE torque.
PUMA was a bit faster at top speed (still around 30 MPH).
But the rear PUMA SCREAMS fast from a dead stop! It really lifts the front of the bike up.
My guess is the Bafang does 1/3 the max torque of the PUMA.

Both motors are very good. I love them both! :D
The single metal gear makes the grade and is MANDATORY for any geared motor IMHO.
Bafang is the "baby" and PUMA is the "daddy".

Aren't TOYS FUN! :lol:

And also first snow fall here in NY. Had to do "donuts" out in the courtyard.
My ebike acts like a motorcycle! Wasted a few WHrs but it left such a cool design in the snow! :roll:
 
^Any chance you can do a fish scale and/or a sonic acceleration recording for each? Short of an open source dynomometer, head to head tests are some of the best measurements we are going to get.
 
Got my 2 metal gears and they look fine to me! Metal should not have the same points to the teeth as nylon! Harborfreight has tool to avoid flying circlips, but I think metric E rings would work fine from auto store! Anyway, I'm running brushed 20" C/L till i finish the Bafang. Soon i hope !
otherDoc
 
New York Snow Storm Bafang TESTING!

I just rode the rear Bafang with metal gear thru 6" of SNOW! To the store and Back!
I could not pedal. But the rear motor PLOWED thru! :D
It was FUN! MY new "SNOW-MO-BIKE"!

Motor got very hot but no gear problems!
(I iced it down with snow)

HECK! This is a lil beast!

What a major difference the metal gear makes.
 
hehe nice knuckles , sounds like fun :)

you only need some snow tyres now hehehe

my 48v bafang still works fine and I can get it super hot , stop and accelerate from the steepest hills , brake and accelerate at the same time but i can't get them into the peanut butter state :D maybe the voltage is too low for that to happen ?
 
Mine were fine on old 48V NiMh, but the minute the new Ping 48 hit them, Peanut, peanut butter!
otherDoc
 
mine is lifepo4 as well , not ni-mh , 48v 10ah with an ecrazyman contoller 30A . it reads 54v off the charger , if I remember correctly. I tried to get the gears into peanut butter state but I can't . Its kinda weird why yours melted with the lifepo4 just like that.... and I can't get mine no matter what I do. I even tried to drag my friend on his bicycle for miles ( quite steep hills as well ) , this did get the motor quite hot then stopped and accelerated from a very steep hill but still no peanut butter. Maybe because its cold outside so heat dissipates quite easily/fast or maybe its just quality control / luck ? It's a rear bafang and I am 130lbs / 65kg

Just thinking out loud...
 
grrrrr grrrrrr grrrrrr
___________

This is not off topic. I thought by now he must be dead and gone; after all, two years ago I cut myself off from all my real friends
because I just wasn't well and did not want to go visit Garland anymore, or anybody. I did not want to leave the house.

Two days ago the phone rang, "Hey, Reid? It's Garland Pobletts. How are you doing? We haven't heard from you and there's a car club dinner
tomorrow; maybe you can come with me and Marie?"

"Garland! You're alive!" "Why wouldn't I be?" "Still have the T?" "Yes, took it for the annual tour, up in Kentucky, this time (he tours with his club,
trailering one or the other of his old cars thousands of miles to the tour-place). Garland is going strong. So is his '15T touring that he has owned and
driven regularly, tens of thousands of miles, since 1957. Garland is ninety years old. He sounds to be just fine. No "grrrr grrrr grrrr".

Oh, how I remember his T. I've serviced its wear-able bands more than once. Garland likes the old style cotton lamp wick type of friction bands,
but they do burn out in a few thousand miles. Yet, Garland's Ford is the quietest running I've ever seen, despite its near-century of service.

T Planetary: The flywheel's rear face bears three stout steel pins. The pins are hard steel, press fit, just so, into the cast iron.
The flywheel runs in oil, dips into the oil sump, constantly wetting itself and the planet pins.

The planets are spur-cut, heat-treated, vanadium steel. They bear bronze bushes, flanged, press fitted, and are a rather loose running fit on the pins,
because

In the heat of an engine, bronze holes grow smaller by quite an amount, whilst the steel pins hardly "fatten" at all.
The gears contstantly spin all the time that the engine is in idle (a couple hundred or so rpm) or in "low" gear.
Only when the car is in its other gear, "high gear" (which is direct drive, no "gear" at all except in the distant rear axle), do the planetaries not spin;
instead they serve to transmit all the power, three spur teeth of steel, to the drive shaft.

Ford planets of steel and their bushings of a very, very particular grade of bronze, run in oil. The gears never, ever break.
Rarely, original bushings wear out to such an extent that the gear meshing is messy, and so, the bushings get replaced.
Then the car is liable to sound at idle, or in low gear, like a coffee mill. Mr T owner of today cannot buy original Ford replacement bushings.
He buys repro bushings. The bronze ain't the same. His machinist reams for what is to be a "proper fit", and knows his onions.
Mr. T owner gets his engine back, refits the engine, takes a first drive and notes "she don't run so sweet sounding as before".

He takes a run up 8% grade Bollocks Hill. He is gonna break in the new bushings, really easy-like.
So he's in low pedal low gear. The planetaries are spinning. Their oil-bathed bronze bushings are doing well, but heating....
and then the lose their oil clearance. One, two or three instantly SEIZE and stall the engine. End of that story.

Garland's old T, old bushings, makes nearly now transmission noise at all. "Reid, you gotta come up, now that you say you are feeling better,
and we'll pull the T out of the garage and you'll go drive it with me?" "I don't know, Garland. I almost died in my own car's death-accicent."
I am an ex-T man now." "I got'cha, Reid. But the offer stands, you know? It'd be good to see you again." The times we had.

As stated, Garland is ninety. He has been driving antique cars since before I was born. He's as fresh and unstripped of mental gear teeth as ever.

-------------
Moral: Metal gears are grand. But they may or may not make a hell of a racket (not even your perfectionist machinist can predict in advance)
Loose bushings -should- guarantee odd and terrible gear noises. But, no. They guarantee plentiful OIL supply to the pinion posts,
and guarantee that each of the three planet teeth (we have ONLY three teeth, at best, in contact, carrying load, at any one time).

POINT: A model T transmission's planet-circle is not large; it works within the orbit described by a nine inch sun gear inside of a cast iron "low speed" drum.
IT SPINS FAST; if you race the idling engine to 2,000 rpm, the velocity of those planets is pretty damn high.
THE TORQUE on those teeth is tremendous: about 90 foot pounds can be applied in service (I am guesstimating numbers here).
IT ALL RUNS IN OIL, ALL OF THE TIME.
Point: metal to metal gearing that runs "fast" and for "long" is by far better off it it can be run in oil instead of mere grease.
But oil is hardly an option for most, leaky gear cases or other special cases.

-------
The Timing Gear of the T (this is not off topic).
I will continue this "lecture" at another time. I'm like, in geezer mode now, snorting derision at "kiddies" thinking that aluminum gears, greased,
are a good wearing thing against tool steel. I doubt it, but can only cite theoretical "no no" reasons. And what really frosts my Mr. Wilson (Dennis' neighbor, remember?)
HOW THE HELL do you who thinks "I'm running one metal and two plastic planets and its just great" plan to walk get home some distant day when your
one-effective-load bearing tooth of (aluminummmmm) busts the eff off, and "peanut butters" your dummy, plastic gears? You might as well leave OUT
the plastic gears. They do nothing if you have a metal planet, or the planet does nothing if you have one or two plastic planets in there;
There is no way, Dennis, that you can mix the races (you see its a figure of speech) and have them all shoulder the bails equal-like).

"Mr. Wilson", old grump, now tells "Dennis" to go back home and leave him be with his single malted, "It's time for my iced tea, young man. Go home now."

---------------- :evil:

Garland Pobletts rang me the other day...... "Reid how are you, we've been worried about you....."
"Are you still working, Garland? I had to quit working myself ten years ago."
"Yeah, I still work two days, doin' that courier work for the company (he ferries vital documents by hand, internationally).
Garland does not rock. He flies, twice per week, aged ninety. Reid only ha-rumphs at a bunch of silly talk in this thread.
It's not that Reid (I use the "third person" for the Queen Victoria-imperious effect) is all correct and infallable.
We are hardly that. But we knows our onions, pretty well, in general. Just don't ask me to hob a tooth or do machine work.
I'm no machinist at all; just a mechanic who fits and fixes and breaks and fixes things, and needs to be left alone now with his iced tea,
just for a spell.

Goodbye now, Dennis-es. Bring your red wagon over some other time? I'll let you clear the cellar of cinders and pay you a quarter.
And I'll tell you of the T's original-type of timing gear, direct driven from the hairpin-crankshaft's, whippy, front end. It is helical cut, a "silent" gear,
but in practice, it is never silent at all. So the aftermarket makers came up with a composite material, starting in 1920, that was truly silent.
This composite, plastic gear, lasted well in good installations. If you can find an NOS silent T timing gear, use it: it's still as strong as new.
It is made of solid linen cloth layers, laminated in Bakelite resin, layers going every which-way, all unitized, then machined from the raw blanks.
And they don't require much lube at all, and they are pure silent, and strong as steel in service.
Today we have some super-tough "reinforced" gear plastics. And I suppose (my "tea is half drunk now) that gears of even this new "improved?"
plastic, would serve a 150 volted Bafang without ever a ba-BANG.

Dialectial materialism-speech, Reid style: "DO THE BURFANG MOTOR PUT OUT NINETY FOOT POUNDS OF TORQUE? DO IT WHIP AN' SNAP
LIKE THE HARMONIC VIBES OF A Ts whippy crankshaft? Do road shocks put to the drive wheel make back-shocks to three spur teeth, ever, sufficient
to snap or deform one tooth? When I break a tooth I go 'owwww'! When a planetary pencil sharpener mechanism gets even one tooth chip, the whole shebang goes BAFANG."

:D

:wink:
 
Cool Reid! Many Chinese geared motors use varying degrees of nylon for 2 out of the three planet gears. My P2A got close to 2000 miles before the bearings on the STEEL gear failed. Its next in line after the Bafang to get repaired! Good to hear your prose again!
otherDoc
 
I got my metal gears today, from Keywin through Voicecoils.

They don't fit. They are a completely different module - my motor is much finer pitch.


My motor is a Suzhou Bafang Motor Science Co. BFY711B11842.

Bugger. :cry:


Oh, and the bearings are stuffed in the new gears. They need to be replaced - which isn't hard.
 
mer said:
mine is lifepo4 as well , not ni-mh , 48v 10ah with an ecrazyman contoller 30A . it reads 54v off the charger , if I remember correctly. I tried to get the gears into peanut butter state but I can't . Its kinda weird why yours melted with the lifepo4 just like that.... and I can't get mine no matter what I do. I even tried to drag my friend on his bicycle for miles ( quite steep hills as well ) , this did get the motor quite hot then stopped and accelerated from a very steep hill but still no peanut butter. Maybe because its cold outside so heat dissipates quite easily/fast or maybe its just quality control / luck ? It's a rear bafang and I am 130lbs / 65kg

Just thinking out loud...

Uh!................... 240 plus 80 lbs of trike could make a Pnut butter difference!??????????
otherDoc
 
Uh!................... 240 plus 80 lbs of trike could make a Pnut butter difference!??????????

I don't think so ... cause as I mentioned above I was draggin my friend on his bike ( without him pedalling ) . I am 130lbs + 60lbs full susp bike (guesstimate) + 160lbs + 40-50lbs = 400lbs . This got the motor quite hot then stopped and accelerated from a steep hill , then pushed the brakes and accelerated at the same time but no peanut butter. That's why I am wondering if it is down to quality control , or maybe the all silvery rear bafang ( which says 8Fun on it ) uses different material on the gears compared to the black one ?! How did you get your gears melted if I may ask ? Accelerating from a dead stop on a steep hill ?
 
I'm going to order a set of metal gears too today, but the post above regarding a gear not fitting is worrying. I have the same black motor from Knuckles, so if anyone has the gear part number then ordering - that would be great.

My motor has just under 2000 miles now, and still running well. I'm still at 66v.

Nog
 
I have run my 36V black/silver bafang on 56V up a hill and from a standing start with about 300 lbs of load without incident, but I parked it as soon as the nylon gear stripping issue surfaced. Its interesting to hear that mer is using a silver bafang and not had problems.

If anyone is sourcing gears, may I piggy-back? I just need one gear. Or, I may just order a silver motor and some gears from keywin (if he has metal gears left).
 
Nogwin said:
I'm going to order a set of metal gears too today, but the post above regarding a gear not fitting is worrying. I have the same black motor from Knuckles, so if anyone has the gear part number then ordering - that would be great.

My motor has just under 2000 miles now, and still running well. I'm still at 66v.

Nog


Mine is a rear Motor, raw ally housing, fully machined.
 
@Nog,

Part number!? ahahahaha

I wish there was ANY level of decent documentation for the motor from the manufacturer.

As a general comment, I wouldn't be supprised if essential the same motor is made by various manufactures and/or small manufacturing outfits. Tooling and designs may end up in various hands and variants of the finished product produced from different places & people. Varying levels of quality may be part and parcel if this is the case.

Anyways. Pop the bafang open, count the teeth on the planetary gears, measure the diameter and compare with what's been posted earlier in the thread.

Dazz and Mark_A_W both have rear Bafang's and both have different planetary gears to me. If anyone plans to order from Keywin, I suggest you include a photo of whole hubmotor and a closeup photo of the model/serial. A picture speaks a thousand words. If he has them he'll sell them if he doesn't your requests might convince him. That's my opinion at least.

I'm busy with xmas stuff at the moment as well as a new road bike (non-ebike). I know many of you are interested in how I go. Rest assured I'll give an update as soon as I've got one to give.

Cheers guys! :D
 
yeh voicecoils, i still havnt figured out which model no my rear bafang motor belongs to... All i have is that serial number like mark aswell. =(
 
Nogwin said:
I'm going to order a set of metal gears too today, but the post above regarding a gear not fitting is worrying. I have the same black motor from Knuckles, so if anyone has the gear part number then ordering - that would be great.

My motor has just under 2000 miles now, and still running well. I'm still at 66v.

Nog

gogo said:
I have run my 36V black/silver bafang on 56V up a hill and from a standing start with about 300 lbs of load without incident, but I parked it as soon as the nylon gear stripping issue surfaced. Its interesting to hear that mer is using a silver bafang and not had problems.

If anyone is sourcing gears, may I piggy-back? I just need one gear. Or, I may just order a silver motor and some gears from keywin (if he has metal gears left).

The black Bafang and the similar silver Bafang will both take this gear.
Just open up the motor and check. It is easy to open the motor.

Metal-Gears.jpg


Just order from Keywin ecrazyman@gmail.com and he will deliver.

-K
 
Yes to the above! I should have my Bafang 1 steel/2 nylon back on the road by the weekend, as soon as all this Bah Humbug &%#@#^^^& is done!
otherDoc
 
Knuckles said:
The black Bafang and the similar silver Bafang will both take this gear.
Just open up the motor and check. It is easy to open the motor.

A noobie question for ya; what's the procedure to open a Bafang motor? What side do I open? Do I need any special tools?

When I first received the motor I took the screws out of one side, I don't recall which side, but could not get the cover off. I didn't try too hard since I didn't know what to expect and I didn't want to damage the case. I am curious to peek inside though and may want to upgrade to one steel gear in the future.
 
It should come off easily, as there is only 1 removable side! Make sure all the nuts are off the axle on that side. You can leave the freewheel on! Remove the screws (carefully) an get flat paint knives under. You may not need em! Just wiggle and it should come off!
otherDoc
 
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