Hi,
I've done some 300km this past weekend and found no issues. It's running really good, but I do still have the noise from the outer gears.
Now I've seen the 2 videos from Bruno ElectricBike where he shows what type of grease he uses and how much of it.
He also says Lithium grease is a definete no - go:
https://www.youtube.com/watch?v=khW5l-FdPU0
https://www.youtube.com/watch?v=3lVRTRFueUU
Firstly, I didn't use that type of grease. I used a rather yellowish grease. Secondly, I definitely didn't apply that much grease.
I'll go to my carshop and ask some of this moly grease.. and give you guys an update on how that works out for me.
Quoting Bruno:
I have seen many completely destroyed pinion gears, all because it was running "dried" without enough lubrication (it was the first problem I had with my BBS02 and first problem many people experienced as well), the damage extends to the big flywheel rounding all gears and you have to replace both. Talking about major service pulling everything apart. The resistance increase would be a problem if we were talking about a very low powered motor like 100/200w without gear reduction. The BBS02 pulls a good 1100w with the factory settings, that means at least 1.3HP on the motor shaft (after thermal loses) and after the 1:21.9 reduction gear we are talking about extreme torque on the flywheel, capable of pulling a heavy rider + bike + battery up hill in wrong gear. Grease resistance mean nothing in this case. Running two metal gears with very high torque is just the perfect recipe for mechanical problems. =]
Another Quote:
Myself and Karl (electric-fatbike.com) are always talking about Bafang mid-drive issues and testing some things to find solution for many problems. Karl tried a heavy duty grease on the nylon gear long time ago and liked the results so he recommended on his website and many people did the same (he is a really nice guy with good intentions). I understand about greases and gears as I worked with million dollar industrial printers and electromechanical systems so I knew heavy duty grease would weaken the nylon and cause premature failure so I refused to do the same, Karl was so happy telling me via Skype conversation and the article was already published for a while so I didn't want to say anything. Many people did put heavy duty grease and had nylon gear failure, obviously everyone blamed Bafang for using plastic gears. Everyone now talks about the plastic gears like it is a problem or weakness in this mid-drive. After loooong time Karl figured out that the heavy duty grease was causing this failure so he rushed to make this article and correct this information so everyone would get this update. I dont criticise Karl at all, he is doing a FANTASTIC job trying so many new things, spending all his money and sharing all his experiences with everyone, we need more people like Karl.
Back to the grease, the first stage is what people called the internal gears, this is located inside the mid-drive and is the contact between the motor shaft and the nylon gear. This is nylon on metal so it requires white lithium grease. The big metal wheel I show in this video is called flywheel, very easy to access from outside, this is the second and final reduction gear. The small pinion gear is also metal so when it comes to metal on metal, moly grease is the ideal as it coats / impregnates the metal providing a long lasting performance (molybdenum is not suitable for plastic).
There is an issue that after many kms a very small quantity of the black grease will leak from the second stage towards the first stage via the bearing seals on the pinion gear. This will only reach the side of the nylon gear and not the actually area where the motor shaft makes contact with the nylon gear. It is unlike that this would cause problems. There is a lot more white grease there so the black grease will be diluted in white grease.
I think this is the longest and most complex reply ever, deserves a video =]
Thanks,
Regards,
Karel