Bafang G310 geared hub - 11:1 reduction ratio!!!

[HrKlev]

Could it use the same gears as G310/311? Those seem to be the same 18-33 gears for both motors and available at least on Aliexpress.

Thanks! Found the shop on aliexpress. They had measurements for the gears, and turns out tve G310 and G311 uses very different gears. I will have to open up and measure the g370, hopefully I can use one of them If not, I'll have to get a roll of nylon filament and see if I can draw it up and print something. Not expecting them to be strong enough, but a fun experiment

 

[TDB]

Could it use the same gears as G310/311? Those seem to be the same 18-33 gears for both motors and available at least on Aliexpress.

Thanks! Found the shop on aliexpress. They had measurements for the gears, and turns out tve G310 and G311 uses very different gears. I will have to open up and measure the g370, hopefully I can use one of them If not, I'll have to get a roll of nylon filament and see if I can draw it up and print something. Not expecting them to be strong enough, but a fun experiment

Do you have links?

 

[HrKlev]

Sure Does this work, or does it just lead to my login or something else? The shop is called
"46 Ebike Store". They also has the motors, so nice to have stored (g310, g311, g370)

https://a.aliexpress.com/_mK6e4jp

https://a.aliexpress.com/_mKETMxD

Update: G370 gears are different to both g310 and g311 unfortunately. I have contacted the seller, but Im starting to think the printer is my only hope if I want to get this motor going again.

 

[ilu]

Sure Does this work, or does it just lead to my login or something else? The shop is called
"46 Ebike Store". They also has the motors, so nice to have stored (g310, g311, g370)

https://a.aliexpress.com/_mK6e4jp

https://a.aliexpress.com/_mKETMxD

I bought by G310 motor from this seller. It was super cheap during a sale, but they did not have the motor in stock even though the page said it was. So it took more than a month before they shipped, when they finally did it arrived really fast with a courier. The motor also was 13T wind rather than 'standard' 10T wind which they told me it would be when I asked. Luckily this was not a problem after all as I use it in 29 inch wheel.

So not the most reliable seller, but at least they do communicate when messaged and I would buy spare parts from them if I needed.

 

[hias9]

12T and 13T seem to be "standard" for the G310. I think the faster windings are only available at Grin.

Take care with the phase amps on your 13T. 30A phase results in the same torque as 39A phase on a 10T. My planetary gears only survived about 200 miles running 30A phase on a 13T.

 

[TDB]

Sure Does this work, or does it just lead to my login or something else? The shop is called
"46 Ebike Store". They also has the motors, so nice to have stored (g310, g311, g370)

https://a.aliexpress.com/_mK6e4jp

https://a.aliexpress.com/_mKETMxD

Update: G370 gears are different to both g310 and g311 unfortunately. I have contacted the seller, but Im starting to think the printer is my only hope if I want to get this motor going again.

That works. Thanks.

I'll pick up a another motor and controller this week. Options are good.

 

[adcockj]

I had asked back on 11 April about the type and amount of oil to add to the G310, so I thought I'd report on what I did...

I bought a 4-oz bottle of SuperLube 100cSt Silicone oil. (The Opticool sounded good, but I didn't want to spend $100 plus tax and shipping to end up with 50ml of oil.)

It was not difficult to get access to add the oil. I didn't drill any holes, but by removing the 6 security torx screws and the 6 Phillips screws around the cassette, I could just lift that cover off (with just a little knife insertion on the edges outside the torx screw locations to get it started). I added 40 ml...probably should have done 50ml, but I just wanted to be cautious.

Everything seems fine. I've done a couple of 25-mile rides (almost 800 miles on the motor now), without any issues.

One caveat: I could not figure out how to get the nut off that holds the cassette onto the drive side axle. (I watched the Grin video, and they said it was easy to remove the jam nut, but didn't show removing the main nut underneath...it was just gone when they pulled the motor apart.) The jam nut was easy, but the 17mm nut itself, which is not a regular hex nut -- just two flat sides -- and sits down inside and is "protected" by a small metal collar, was another story.

The way I removed the cover for access, it wasn't necessary to get this nut off. But if/when I need to be able to remove the sun gears, I'm going to be in trouble since I couldn't get to the screws underneath.

Is there some special wrench that would grab the two flat sides of that nut? Or do I need to just grind that little collar back?

 

[Yamarlo]

I went for 10 Cst pure Silicone Oil. Lower viscosity meens less drag, but i had small problems with leaking. Nothing wild but next time i would go for minimum 20 Cst. I also added PTFE for less friction in the gears.

Silicone oil seems common for plastic (nylon) gears. I found a source with more information about compatibility of different kind of oil for different materials and a guide which oil und additive to use.

https://ecllube.com/resources-for-engineers/







Regarding the nut, i used a plier to hold /lock the nut and turned the axle from the other side of the motor with a wrench.

 

[neptronix]

You should really try opticool. Their site lists the kinds of materials opticool-H is compatible with. I quizzed them and it seems to have the highest material compatibility of any coolant i've seen.

Do let us know how silicone oil goes. One big thing you need to know is if the fluid is compatible with nylon though, as your gears are likely made of it. I would guess that opticool H is rated to be compatible with nylon.

 

[1N4001]

One caveat: I could not figure out how to get the nut off that holds the cassette onto the drive side axle. (I watched the Grin video, and they said it was easy to remove the jam nut, but didn't show removing the main nut underneath...it was just gone when they pulled the motor apart.) The jam nut was easy, but the 17mm nut itself, which is not a regular hex nut -- just two flat sides -- and sits down inside and is "protected" by a small metal collar, was another story.

The way I removed the cover for access, it wasn't necessary to get this nut off. But if/when I need to be able to remove the sun gears, I'm going to be in trouble since I couldn't get to the screws underneath.

Is there some special wrench that would grab the two flat sides of that nut? Or do I need to just grind that little collar back?

Yeah, I had the same problem. That nut is often on so tight that it can't be loosened, and I could not find a tool that would fit in there to get a proper grip. I wonder if Grin has an unusual tool that gets in deeper.

 

[Major Clod]

I'm looking at building an e-bike for my son using a spare 20" MTB frame. The G310 looks great to me given its light weight. I'm trying to choose between the standard and fast windings from Grin, so looking for some insights on which way to go based on the following.

- primary goal is to extend gravel riding range and also use to assist his climbs on singletrack
- expected bike + rider weight 40-45kg
- used in 20" wheel now, 24" wheel in 12-18 months time
- torque pas only, no throttle (he still needs to put some effort in!)
- max target assist speed is 25kph
- likely 36v battery but open to suggestions (probably get a custom pack built locally to fit his frame)
- using the CA3 to keep it all easy

He's a fantastic rider already, and the goal is to just help him keep up with mum and dad for longer rides, not setting any land speed records etc.

Any thoughts are most appreciated.

 

[HrKlev]

Standard wind on 36v will do about 29kmh in a 20" and about 33kmh in a 24" according to the Grin motor simulator, so no need for the fast wind. A baserunner, cycle analyst and a bottom bracket torque sensor would give you what you want (you can use whatever controller you want with the cycle analyst, but the baserunner is plug and play without soldering, and it is very compact). You need to configure and finetune the baserunner and cycle analyst to get the behaviour like you want, but its not a huge deal if you are familiar with diy stuff.

Another option would be a KT controller that is flashed with open source software. That would do torque sensing, but I think it is a bit more fiddling to get it to work.

 

[Major Clod]

Standard wind on 36v will do about 29kmh in a 20" and about 33kmh in a 24" according to the Grin motor simulator, so no need for the fast wind.

Awesome thank you, that confirmed my own thoughts!

 

[Yamarlo]

I went for 20 Cst pure Silicone Oil. Lower viscosity meens less drag, but i had small problems with leaking. Nothing wild but next time i would go for > 20 Cst. I also added PTFE for less friction in the gears.

Silicone oil seems common for plastic (nylon) gears. I found a source with more information about compatibility of different kind of oil for different materials and a guide which oil und additive to use.

https://ecllube.com/resources-for-engineers/

Screenshot_20210422_215145.jpg

Screenshot_20210422_215449.jpg
Screenshot_20210422_215209.jpg


Regarding the nut, i used a plier to hold /lock the nut and turned the axle from the other side of the motor with a wrench.

Edit: went for 20cSt not 10

 

[alfy22]

Hi,
Im having issues with my e-bike build and G310 motor. I have a Grinfinion 20A controller and my build is set up with pedal assist. I use my ebike as a daily commuter and everything had been working great going on 3 years, but now when I pedal, the motor just shudders and then I lose all power. I have ruled out battery and PAS issues. Checked controller mosfets for shorts and that all seems ok although the resistance on one phase wire was less than the others, around 2kohm. I assumed this was ok or could this be an issue?
I disassembled the motor and noticed what looked like a bit of corrosion on the stator and coils - nothing major, see pictures - a bit of white oxidation on the outside and rust on the inside of the coil casing. otherwise everything looked ok including hall sensors.

Could water have damaged the motor? Could this be the issue and is it fixable/replaceable or do I need to replace the entire motor? I live in Norway and use the bike year round in pretty harsh conditions- rain, snow, salted roads etc so it would not surprise me but expected it to last longer…

Thanks for any help
Kris

 

[TDB]

I had my G311 apart this week for a check up. Better part of six months and 15,000km since potting the windings and board, also no internal wires exposed. Using ATF as the lubricant and coolant. Looking good, like new... but I didn't take any pics.

 

[john61ct]

deleted

 

[Hawaiianr808]

I went for 10 Cst pure Silicone Oil. Lower viscosity meens less drag, but i had small problems with leaking. Nothing wild but next time i would go for minimum 20 Cst. I also added PTFE for less friction in the gears.

Silicone oil seems common for plastic (nylon) gears. I found a source with more information about compatibility of different kind of oil for different materials and a guide which oil und additive to use.

https://ecllube.com/resources-for-engineers/

Screenshot_20210422_215145.jpg

Screenshot_20210422_215449.jpg
Screenshot_20210422_215209.jpg


Regarding the nut, i used a plier to hold /lock the nut and turned the axle from the other side of the motor with a wrench.

Have you looked at usuing ATF?

 

[1N4001]

I had my G311 apart this week for a check up. Better part of six months and 15,000km since potting the windings and board, also no internal wires exposed. Using ATF as the lubricant and coolant. Looking good, like new... but I didn't take any pics.

You mean you actually potted the components in epoxy? Was that a lot of effort? And did you remove the gear grease or leave it in?

 

[TDB]

I had my G311 apart this week for a check up. Better part of six months and 15,000km since potting the windings and board, also no internal wires exposed. Using ATF as the lubricant and coolant. Looking good, like new... but I didn't take any pics.

You mean you actually potted the components in epoxy? Was that a lot of effort? And did you remove the gear grease or leave it in?

Yes, E2224 encapsulation epoxy, no but there are a few tricks and it is lubricated by ATF.

 

[hias9]

I have a few thousand kilometers on my G310 now and yesterday there were vibrations coming from the motor the first time. Those vibrations can be best felt on a good tarmac road.
Today I had those vibrations at least on 10 occasions, sometimes only for a second, sometimes the vibrations are there for about 10 seconds before they disappear.
Do you guys also have those vibrations sometimes?

 

[Jil]

Has anybody paired this motor with Bafang PAS, display and controller ? If so, which ones and what is your impression about them ?

 

[Jil]

Hello !
I just reach the 2700 kms mark with my G310, after 3 months 1/2. Still very happy with this little but powerful motor. I'm using it generally at 600W above 25 kph, and 450W below.
Question for the long range users : what is the duration I can expect from the nylon gears with such use ? Just to know if I should order now a set on ebikes.ca

Hi !
2 years later, has anyone got the answer (duration of the clutch and nylon gears) ?
If there has been some high mileage reached with a G310/G311 motor, I would like to know more

 

[TDB]

Can't read?

 

[Jil]

Can't read?

I have seen your post, TBD, but I’m just asking for more reviews if any :wink:
So you have made 15.000 km running with oil, and your G311 is like new. This is a good start !
What is your nominal/max power use ?