definitely 
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Bonus points for someone who figures out how to DIY a Rungu style bike front end with two BAFANG hubs.
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Skateboard pusher trailerā¦ using a BAFANG pedal sensor hackā¦ so as the board wheels speed up the motor hub power ramps up.
To many ideasā¦ floating out there.
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hey @Guy746 been testing my batch of 200 30q, 3 were lower voltage than the rest, Iāve unwrapped several and found rust around the positive terminal
Iāve also been finding cells with dings in them, this is one of the worst
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Hey Scepterrā¦ no worries, just send a message in and the guys will work with you on it.
Keep in mindā¦ your not dealing with NASA spec batteries when your ordering lots of 200 at ~25% the normal retail value. ( I am just guessing at the 25% by the way. ) Even with batteries new in boxes, you might find some that where returned back into someones inventory before it got to us. The batteries that are new in original boxes are often the ones that have been sitting in the warehouse somewhere the longest.
With that long on a shelf, seeing only 3 with lower voltages out of 200 is pretty solid. If the cells had issues, you would see a very significant voltage drop after all that time.
A voltage drop test is generally where you charge all the cells up to the top and let them sit for a week and retest. Thatās the first step in weeding out your bad cells. Then you want to run them through a capacity test. The capacity test numbers will be what helps you dial in the best to the worst.
I would charge up several of them up including the 3 you are concerned about and then set them aside for a whileā¦ Check their voltage from time to time. Bad cells will also feel warm to the touch while charging or immediately after chargingā¦ If they are smoking with flames shooting out the ends, thatās also a sign something might be up with them.
When your building large battery packsā¦ you always want to start with more cells then you really need. You will weed out the bottom percent as you go. One thing you get with $4 and $5 cells is that someone ( in an ideal world ) has done all those steps. They buy cells wholesale market at .50 to 1.50 each, test them and then sell them them for $3 to $5 each.
Rustā¦ If your not seeing it on a lot of others, I wouldnāt stress about it too much. The caps do not look scuffed so they donāt appear to be recycled sold as new. Dentāsā¦ not something anyone has mentioned before over the years, but most of us are not taking the wrappers off. It is in a section that gets crimped down during the manufacturing process.
anywaysā¦ just reach out to the support team and they can work with you.
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Lol I like you guy
Interesting info, thanks!
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Really good to see that you guys clearly know what youāre talking about. I really hope to see more deals in the future targeted towards us as youāll many of the people here will happily drop hundreds instantly on a good deal (I would if I could get shippingā¦). This is a really great option for everyone, good to see some competition
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This is the place to find the info. Quite a few people have built with these now and there is a variety of way to connect them
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I am thinking about having my order shipped to a freight forwarder in California as soon as I have spare cash and there is a good deal.
So far I found out that the only way I would get bare cells shipped here is by sea. Whatās fucked up is that it is not cheaper than by air, go figure.
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Oh shit my understanding was that it would be WAY cheaper. My issue is that all the forwarders require you to set up a business account with them to ship by sea, or they simply wonāt ship batteries. Not sure if itās worth bothering at this point
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Well last time I enquire with a local company that has offices in The US and in EU, the cells I was looking to import were from Europe.
I think I am mixing stuff up there sorry about that. All in all, shipping + handling at the port here and custom brokering (basically all the way to my hands) the overall cost was like twice the cost of the cells.
none of my bikes have bolt holes on the front forks so I would need a torque arm like this:
I donāt even think the 100mm dropout will fit any of the forks I have but Iāll see.
if the gearbox in this motor is similar I wonder if you could weld the clutch bearing to make it drivable both directions.
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As a rule of thumb, Iād recommend that you use a fork thatās setup for a disc brake, most forks only really setup for the radial load of the wheel, with the moment arm while braking acting more on the steerer tube than the fork ends.
With ~350 watts on an ebay ebike ESC, probably not a huge concern, but if you plan to pump in some amps with a vesc, something to consider. (also bonus regen brakes if you fix that clutch).
(Mostly making this statement since most modern fork spacing is 100mm, (Iām counting disc brakes being āmodernā) Older forks may be narrower, and some early adopters of disc brakes brazing on attachments had issues snapping forks from the unexpected forces.
If youāre talking downhill bikes with a 110mm spacing, Iām probably rehashing old news to you, but I figure itās worth mentioning for anyone passing through)
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Just looked at the lyft bikes here in SFā¦ they appear to be just a jump bike rebrand. So these bikes are still around and kickin with these same parts.
Kinda jealous though i dig the hot purple rimā¦
Think ima rent one later today on lunch and check it out. If anyone is interested or has a question. Lmk.
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FYIā¦ The silver pack inventory ( SPIM08HP 3.7v 8ah 200a ) is almost all goneā¦ I belive we where the main source for awhile so the market prices will shoot up on those.
The car guys buy them ~1,000 units at a time. If you have any plans for them in the future, you problable want to get them sooner than later.
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Considering that it costs an arm and a leg to send cells internationally by air, what options are you aware of for sending cells internationally via sea freight?
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This is also my question. Too bad the SPIMs are almost gone, I am one of those car guys
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Did we hit any bonus levels on the wheels?
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