@hummie, notice in this last chart you posted the motor amps are the same in both motors at the same speed so the motor efficiency is the same as well, like the first chart I posted showed same efficiency at the same speed and same motor amps.
heres another:
showing bit higher motor amps for the lower voltage system at same speed but same torque, yet overall eff is still showing about the same. at this point it seems the difference in eff will vary with the details but the lower voltage is showing a hair better eff.
but i was confused by what you wrote @professor_shartsis and thought you were saying otherwise.
In your latest graph i suspect the decrease in efficiency with 12S at the same speed & same motor amps is entirely explained by the higher total internal resistance of the 12S battery as opposed to the 10S pack and has nothing to do with the motor or controller. notice the difference in efficiency between the 2 systems in this condition is about a third of 1%. i strongly suspect the entire decrease in 12S efficiency shown in the graph ends up as extra heat in the battery pack.
the grin simā¦ ā(it does not take into account the losses internal to the battery pack)ā
at partial throttle the diferences are small yea but when the 10s gets to top speed, no more pwm, it has that advantage over a 12s at partial throttle and I think a lot of the losses are the esc switching for the partial throttle 12s
can you explain why it shows system A has higher efficiency but system B is shown to be consuming less watt hours per kilometer?
yea i noticed that but at the same time they arent exact comparisons and the 10s is doing a bit more work
scond week of august. thats when tires will be shipped. so they just told me. not sure if thatās within the 6 weeks they told me initially or just afterā¦o well im still happy.
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Hi Looking to sell my spot. Shoot me a pm if interested
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tbh i would be good at 100mm tires, as i dont plan on making a 4wd systemā¦ but if the price is right, i may do a 4wdā¦ idk
Iām just soooooo impatient to ride theses on a daily basis !!! Trash the meepo hubs and use this piece of art.
Maybe in September 
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Shoot me a PM if your still wanting to sell them.
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So we are in that second week of August. Any update on the wheels being shipped?
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ill write them on monday and see whatās up.
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Iām going to reply to this in here. I think you should do a test between the different bearings and greases like @CHAINMAILLEKID has done on his YouTube channel. Personally Iād rather have the high temp grease since it should last longer and will be more resilient to water.
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Heh sounds like as usual real bearings cost $30 and the chinese have made something that looks like bearings for much much cheaper.
@hummie Iād pay $40 if you could pack the jap bearing with high temp grease lol.
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There are different bearing manufacturers that make various qualities of bearings, but there are also different grades of the same size of bearing that are intended for different purposes. In general, the grease packed sealed bearings are for use in high-speed environments (20000RPM -100000RPM) environments where they canāt be easily replaced. Theyāre sealed so they canāt be service, but they canāt be contaminated or have the lube leak out. There are less expensive āshieldedā versions with the plastic shields that can be opened and re-lubed and can run on light grease or oil lubes. They have less rolling resistance but will overheat at higher RPMs and can get contaminated thru the shields and can leak lube.
Iām rebuilding a couple of cheap hub motors (just for fun/experience, makes no financial sense), and my experience sourcing bearings is similar to what @Hummie describes. My inboard bearings are nice Japanese 6903Z with metal shields and the outboard are less nice but still good 6801RS with removable plastic shields. They spin nice and are good bearings, but in order to service them you have to completely disassemble the hub, and the bearings are press fit into the inner and outer wheel plates. It should be really hard to take them apart because they are tightly fit onto the shaft. Except, exactly like @Hummie describes in:
the inner rings have begun to rotate on the shaft, especially the inboard bearing, and now they slip on and off the shaft easily and thereās a very tiny bit of wobble on the inner one (between the inner ring and shaft, the bearings themselves are still tight AF). Luckily all the wear seems to be on the bearing inner ring and the shaft is just a little shiny in a couple of spots so the new bearings I got to replace them are tight enough they canāt be pressed on by hand.
Iām replacing them both with nice ZZ versions from vxb.com, which are sealed with metal shields, and packed with grease, good for ~30000 RPM. I could use cheaper oil-lubed, shielded bearings, but because Iām going to reassemble them, pressing the new bearings onto the shaft with retaining fluid, I donāt expect to ever open them up again, and I want to use bearings that should never need replaced or serviced. If the hubs were easily serviceable, Iād use slipperier oil-lubed bearings, but since theyāre going to be crazy hard to open up, Iām going with long-lasting, bulletproof bearings. Reliability and longevity are more important in this case than lowest rolling resistance and serviceability, since they canāt be serviced easily anyway.
A good comparison test between various bearing types and manufacturers would be awesome and super helpful, but a huge pain in the ass to do, cause youād basically have to build a set of hub motors for each set of bearings you wanted to test, or switch them out, which is going to be hard work + you risk damaging the motors every time you press out the old bearings and press the new ones in.
Thatās going to be a huge innovation in hub motor design, a way of making the bearing serviceable or replaceable without compromising the connection of the inner ring to the shaft, the outer ring to the wheel, or opening them up to contamination from outside.
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I bought 100 608 bearings from them on ebay like 10 years ago. Crap crap crap. Ran through them super fast. I use the corpses to help press bearings into wheels.
I hope theyāre better now, or have non-crap bearings to sell outside of ebay.
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No kidding, I thought they had a pretty decent reputation. I wouldnāt replace the ones that I already have if the inner rings werenāt reamed out and loose. The bearings I got seem fine, but canāt tell by looking at them. They werenāt cheap but they werenāt the most expensive I could find either. Frankly, the motors theyāre going into arenāt that great so the bearings will probably outlast them. Guess I will find outā¦
So, one thing Iāve come to learn pretty quickly since coming here. The use case for bearings between Eskate, and normal longboarding is pretty different.
People here put A LOT of miles on bearings, and thereās a lot of traditional skate wisdom that just doesnāt account for such extended use.
I bet riders like Deckoz have a single set of bearings with more miles on them than I do across my entire collection of bearings.
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tires are done and heās hoping to ship them by the end of this week
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