1st gen TBDD, have a smaller sensor connector 
it was either jst ph 1.5 or 1.25
Will mbs matrix II be ok to hit 40 mph?
Many half decent trucks are okay to hit 64km/hr. Just know that at that speed your board practically flies over most terrain debris, but holes in the road will still really fuck up your balance or straight up eat your wheel.
From there, either the hanger, the baseplate, the deck or your legs will break (or any combination of these 4)
In short, matrix 2’s are good enough. Not the best, that goes to forged metals which will cost an arm and a leg
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Ya I will probably end up gearing it for around 32 mph and have more torque but I wanted to know what would happen if I was going downhill…
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I am geared for 68km/hr and actually hit that 64km/40mph regularly on cnc caliber 2 trucks. It is fun, but also the kind of thing that can get me on the suicide watch lol.
You want speed, absolutely go for it. You want torque? Don’t gear 75% of the way into speed mode.
I’m assuming you’ll get pneumatics because of the truck choice. This will never reach over the speed you are geared to because of the losses, but if you do gear too low and prove me wrong, you lose brakes over 100% duty cycle
I was planning on going 7” pneumatics
I’m reading conflicting information on maximum discharge voltage for Li-Ion batteries. Generally, I’ve read the absolute cutoff to be around 3.2 to 3.3V per cell, but looking at percentage charts, it seems like anything under 3.6V is basically already dead.
However, looking at Li-Ion handbooks and datasheets, they seem to give far steeper minimums for the batteries, with one showing minimum charge voltage being at 1V!
So now I’m wondering how hard is it actually to kill a cell? Given that energy delivery is nonlinear and voltage drops off sharply near the end, is there any reason not to set the hard LVC limit somewhere relatively high like 3.6 or 3.7V?
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A huge reason…there is a lot of charge still left in the cell at those high voltages! 3.6V-3.7V is the “nominal” voltage for a standard Li-ion cell and where most of the capacity is. Stopping at those voltages could leave 50% of the cell’s charge still available.
That LiPo table a very conservative set of numbers with just crazy high recommendations for where you should consider a cell to be empty. Empty is typically considered to be around 3.0V but that is a number chosen to help extend the life of fragile LiPo cells. They aren’t truly empty until a ways below 3V.
Standard round Li-ion cells are typically rated down to 2.5V and are considered “empty” at that voltage though there is still a few mAh of charge still left.
That second graphic doesn’t show 1V as the minimum charge voltage. That number is just a recommended safety limit in case of a huge overdischarge. They are saying that if the cell is still over 1V you could recharge it (slowly!) and use it. That second graphic sets the discharge cutoff at 2.5V.
Some cells get damaged below around 2.0V so staying above 2.5V is my recommendation.
You won’t even damage a standard li-ion cell by going down to 2.5V (just age it normally) as it is rated to do that hundreds of times. You typically won’t kill it by even going down a lot further than that but you could damage it.
There’s just not a lot of charge left in a li-ion cell at below about 3.0V so that can be a decent cutoff to use as it helps extend overall cell life. Even down to 2.8V or so.
What you see online might be a conservative low voltage cutoff point to help extend overall cell life or it could be the manufacturer’s hard limit. Be sure to find out which number it is you are looking at.
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I feel like that’s for a perfect textbook pack. In a real-world pack that’s seen some use with some drifting internal resistances, the lower you go on a BMS-bypassed pack, it gets far, far, far more risky that some P-packs could see those voltages, even while the whole pack voltage is higher.
I would not go that low in real world use if your BMS is bypassed. If you’re discharging through the BMS, that’s a lot better.
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Anyone know anything about mailing an esk8? I’m going to Florida for a week and a half, and would love.to show my creation off to my family. I know I have to ship the battery, but realistically how expensive/how would I bring my board? Taking it on the flight somehow is also an option
Going down to 2.5V/cell presents no problems for the cell…in any pack.
If the packs’s voltage divided by the number of series cells ends up resulting in cells going below 2.5V (or whatever limit is set) because of the pack not being well enough balanced that is an entirely different issue. 
I agree it’s a concern though, and with your recommendations, and is why we should set low voltage cutoffs higher than 2.5V/cell. We have to separate that conservative practice from what the cells are rated to do every cycle though.
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That’s the issue to which I refer.
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NYC to Florida? U can ground ship it few days in advance, so it will arrive about same time as u land there. In general, aircraft carry on battery cannot exceed 199Wh for standard regulation, of course there are exceptions, but those are either medical device / military use, or pre approved by the airline and TSA
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I’m blanking on what the name of that new ESC that looks almost exactly like a Unity is. Help a brother out
BKB Zenith? Xenith?
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Pelicase Question: is it necessary to drill in them to use them as a monster box type thing? Presuming yes (and so also concerned about liquid getting i)
Any idea on how much a 20lb longboard would cost? Calculator isn’t working rn
