Help finding a solution to Bafang gear stripping

[docnjoj]

I agree about the low noise level with 1 steel and 2 nylon gears on the Bafang. It sounds about the same as the all nylon motor! More testing (by me) needed but initial results are promising. I am VERY sound sensitive!
otherDoc

[MotorSmoke]

I don't own a bafang motor, but I do desire one. After much reading on this forum, and particular about
this motor, it occurs to me if one drills some holes around the outside body of the motor, it would allow a lot
of cooling that does not otherwise happen very well. This may solve two problems, both the melting gears and
allow extended high power operation; after all, electric motors are mainly limited by the ability to get rid of heat.
I would think that unless one uses it in very dirty conditions holes would be just fine. Water would be continue to be
flug off the motor and would hardly get inside during use, and the holes drain during a rain.

Just some thoughts.

[zukster]

I just followed this thread from start to end - whew!

I noticed that its been a general observation that a 26 inch specified bafang in a smaller
wheel does not tend to wear the gears as bad.

I just wanted to point out that some of the Bafangs come for a 28 inch wheel. This may
give similar results in a 26 inch wheel, albeit only a few percent improvement.

http://www.szbaf.com/en/Product.asp?CategoryID=275

[docnjoj]

After about 200 more miles the Bafang is still fine. I am avoiding taking it apart for regreasing cause Im lazy!
otherDoc

[zukster]

I just wanted to post a follow up here because I bought a whole bunch of metal and nylon
gears from keywin about 6 months ago, but I've never had to use them. I originally bought
them because I was getting the motor too hot when running it with the 2nd size up
Infineon controller 30a/600w jobby. Ended up smoking the motor and melting the gears
a bit running it with 40v and 60v Can Tire Yardworks battery packs.

I ended up buying a new motor and switching back to the 20a/350w little controller.

I've been running this now at 40v and 60v for over six months now without any problems
at all, pulling a trailer + 5 year old + car parts + much ruthless hill torture (to really test it)

Its really quick at 60v. Should be plenty of power for most people.

If you're looking for a safe setup without overheating the motor or controller, I'd say
don't try to push it more than the above. I was even too lazy to use a fuse and have
not had any problems. But you really should use a fuse - it might have saved my little
controller a few weeks ago when I accidentally hooked up 4 20v Yardworks batteries
in series = +80v - don't ask. Hopefully I just have to put a new 63v cap in that blew.
But a fuse might have avoided any damage in the first place.

Anyway, no gear problems at all in 6 months at 40v and 60v with the little controller.
Maybe I'll use the gears if I do some maintenance on the motors in a year or two.

edit: I think Keywin is suggesting limiting to 48v battery packs for this controller now.

My posts re opening the Bafangs and other testing were here:

http://endless-sphere.com/forums/viewtopic.php?f=2&t=9969
http://endless-sphere.com/forums/viewtopic.php?f=2&t=10094

[richerson]

Hi all

Just like to report my experience with the bafang, I have a rear one in a26" wheel with 66..6v lipo pack and a 72v 45amp infineon controler. I live in London and ride 12-20 miles most days and have just clocked up 1000miles. No problems so far, doesn,t overheat, but it is a bit more noisy know. Lots of stop start riding but mostly flat terain. This little motor is awsome.

[zukster]

Hi all

Just like to report my experience with the bafang, I have a rear one in a26" wheel with 66..6v lipo pack and a 72v 45amp infineon controler. I live in London and ride 12-20 miles most days and have just clocked up 1000miles. No problems so far, doesn,t overheat, but it is a bit more noisy know. Lots of stop start riding but mostly flat terain. This little motor is awsome.

I had a similar setup with a 30amp controller and a 60v battery pack. And I burnt out the motor. It was most likely from
my batteries sagging, but yah, sounds like 1000 miles should be enough to tell.

Nice to know the Bafang works at 66.6v reliably if the setup is done right.

[Russell]

Hi all

Just like to report my experience with the bafang, I have a rear one in a26" wheel with 66..6v lipo pack and a 72v 45amp infineon controler. I live in London and ride 12-20 miles most days and have just clocked up 1000miles. No problems so far, doesn,t overheat, but it is a bit more noisy know. Lots of stop start riding but mostly flat terain. This little motor is awsome.

Interesting,but I think the flat terrain is what really helps keep your Bafang from melting. BTW, what model Bafang do you have? Do you have a wattmeter on your bike to see how much power you're actually pulling? What is your average and top speed on a normal trip?

By comparison I'm pretty easy on my Bafang running it at 48V with a 15A controller but I still can heat it up pretty good with sustained speeds over 20 mph (32 kph). So far I have over 2,700 miles on mine and hope to put on many more.

Hmmm...maybe that famous London fog effectively wicks the heat away from your motor and keeps it exceptionally cool

-R

[zukster]

By comparison I'm pretty easy on my Bafang running it at 48V with a 15A controller but I still can heat it up pretty good with sustained speeds over 20 mph (32 kph).

I go a bit more than that. 15a and 60v and lots of hills, trailer, 5 yr old. I can get it warm with 10-20 minutes
of sustained abuse, but not hot like when the other one burned up. By warm I mean the motor or controlled
won't cause you to pull your hand away when you touch them.

I'm sure the flats help at the higher amps and volts. Try some big hills if you can find some and let us know.

[richerson]

Hi

I don't have a watt meter on this setup, top speed is 27mph off the charger then settles down to 24mph after a couple of miles. Doesn't take many seconds to get to top speed but probably only keep top speed sustained no more than 2-4 miles as there is lots of trafic here. I would of thought starting off the lights would heat it up more than cruising at top speed?

[zukster]

Hi

I don't have a watt meter on this setup, top speed is 27mph off the charger then settles down to 24mph after a couple of miles. Doesn't take many seconds to get to top speed but probably only keep top speed sustained no more than 2-4 miles as there is lots of trafic here. I would of thought starting off the lights would heat it up more than cruising at top speed?

I found that hills tend to cause the motor to draw the most current. A few seconds to top speed won't hurt anything
if the motor, wires, and controller electronics are beefy enough. Any hills you can try? Jump off every couple of
minutes and check the motor and controller for heat.

[SoSauty]

I took an intro CAD (computer assisted drafting) class last year and plan to take the 2nd class Spring 2010. We were intro.ed to some niffy machine (looks like a big copier) that produced plastic pieces from your file, drawn in CAD, and saved on a thumb drive. Recall the instructor saying you could send your file to China and get someone to manufacture your design with enough $$$!

Now in this same classroom I'm taking another prerequisite course for CADII. There's a poster about a reengineering contest using the CAD and this niffy machine. Last years' winner designed a plastic cell phone holder for motorcycles. I wonder if this niffy machine could produce 1 or 2 or 3 bafang or Ezee or BMC gears out of some tougher material, someone mentioned Honda valve gears are a Tough plastic material

The info on this thread is almost overwhelming. What plastics are tough, and what bearings? With summary input, and your patience, I could pursue this. If this niffy machine won't tolerate anything but soft plastic it's a no go, otherwise maybe. . .

[Papa]

The info on this thread is almost overwhelming. What plastics are tough, and what bearings? With summary input, and your patience, I could pursue this. If this niffy machine won't tolerate anything but soft plastic it's a no go, otherwise maybe. . .

One of the primary reasons for plastic gears, is that they can survive on minimal lubrication. While I have yet to see any longevity reports of those using replacement 'metal' planetaries, I would wager that noticeable wear will be evident (on all the gears - including both the sun and ring gears) unless the user frequently re-lubes - especially during higher loading outside of the manufactures' designed limits. This is one of the reasons why typical gearboxes (those that use metal gears) normally use gear oil in lieu of 'grease'.

[Crash Machine]

Does anyone know if the Fusin and Bafang motors gears are the same? I'd like to try some metal ones because I just broke a gear on mine. It's already fixed, Steve at Worldwide sent me the whole gear assembly but I've been watching this thread with interest.
I run at 22 amps 48v and was pulling about 70 lbs. plus weight of the trailer plus my bike at 77 lbs. I weigh about 140 lbs. Pulled out without peddling much and SNAP
When I put 'em in I just put enough gear lube to coat the gears is this right? Anyways I thought this picture would fit in this thread since the motors are similar....

l_fef98a6b53bf424e9f1f4cd5df00179f.jpg (40.61 KiB) Viewed 502 times

[John in CR]

Crash machine,

The gears are definitely not the same. I have both, and have them both opened up. Let me know if you track down an appropriate metal gear for the Fusin, and I will do the same, because I'd like to add a metal gear to the mix.

John

[jateureka]

What were the conclusive results of all the testing?
One metal gear and two nylon?
three metal gears?

For a front wheel hub motor s/n BF803D10230 36V 200W, for 26" but mounted in 20", I don't see a model number.

[docnjoj]

My newer Bafang has not had any problems at 54 volts in over a year of regular use. Prolly 1500 miles. All nylon gears.
otherDoc

[johnrobholmes]

I think it ultimately depends on the wheel size. If you are riding a 26" wheel, I wouldn't push them more than 12s lipo or 16s life and 20a battery/ 45a phase limiting. On 36v it seems that 25a/ 60a limiting is acceptable. The smaller the wheel, the more power that can be pushed through the plastic gears.

[Russell]

What were the conclusive results of all the testing?
One metal gear and two nylon?
three metal gears?

For a front wheel hub motor s/n BF803D10230 36V 200W, for 26" but mounted in 20", I don't see a model number.

I just recently retired my Bafang after over 5,000 miles but it wasn't because of any problems with the original gears. I used the 36V motor at 48V for 80% of those miles with half of that at 15A and the rest at 20A. I do use my motors for assist rather than the prime motive force but I do have hills though nothing very long. Still I have gotten the small geared motors I have run pretty hot from time to time, enough to melt the internal hall wiring insulation on one 24V model running at 48V, but the gears never were a problem for me. My thinking is if you are running the little motors at power levels high enough to puree the gears then the motor itself won't last very long despite switching to metal gears as something else will likely fail. In my experience hall problems on a Bafang are the more common failure mode.

-R

[jateureka]

Sorry for the poor wording in my first post.

The plastic gears are stripped after about 12 months use. I am looking at alternatives to just replacing with 3 more plastic ones and was wondering if just one metal with two plastic could be a marked improvement.

The motor details:
front wheel hub motor s/n BF803D10230 36V 200W, marked as 26" but mounted in 20" rim for more torque.
This is in a delivery trike that uses 36V LiPo with 15A controller and carries up to 40kg load plus rider. Ambient temperatures can get up around mid to high 30s degrees C.

[docnjoj]

I did the 1 steel 2 nylon replacement on my older Bafang and rode it for about 2 years without problems on a 20" wheel. This after peanut buttering the older nylon gears. Only a slight increase in noise level. Worked fine.
otherDoc

[jateureka]

Thanks for the reply otherDoc.
I'm hopeful that one steel planetary gear with two nylon will work for this setup too, although I haven't stripped it down yet to confirm no other damage.
Who did you order your gears from?

[brumbrum]

I've just finished reading this 22 page thread and thought i'd bring it back to life. has there since been anymore failures with or without the metal gear?
I'm in a similar situation with a Golden Motor '902 prokit' which is geared and rated at 36v 250watt. I have not received the motor yet so have not had chance to take apart. i want to run it with a 54v 20ah lithium-ion pack. What would be a safe cantinuous and peak amp limit? 26" wheel btw.

has anyone had any expereience with the above motor?

Thanks

[zukster]

Finally after 3 years of use, my son stripped the nylon gears in his rear drive Bafang SWXH 26
Inch wheel model being run by Ecrazyman/keywin 350w/20a Infineon controller and 60V to it.

I had already ordered some metal gears from keywin a couple of years ago (I don't know if keywin
is around anymore), so I just had to install them. One of the nylon gears had actually cracked and
jammed the motor. Not wanting to take anymore chances, I used 3 metal gears.

Its not too loud when the motor has been treated with ACF 50 or fluid film inside to protect it.
See viewtopic.php?f=2&t=12984&start=60#p218898

Also a note. The insides of the motor are in good shape, so the above treatment worked and
did its job of protecting the motor though a couple of winters.