Belts definitely have a whinier pitch then gears or direct imo. It could be your idler rattling a bit. Do your belts stay centered when hand rotating the wheels forward and backwards or do they want to walk off the pulley a bit?
Nope, not for me. I did grab them second hand though. I wouldnāt have connected in the wrong polarity.
Would I measure by tapping the prongs to the positive and negative awg wire going to the vesc pcb?
The whine itself is pretty new. The right belt stays in the same position, but the left one wanders when turning backwards (donāt drive backwards)
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Iād tighten all the bolts and not worry about it unless you feel performance problems.
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No problems at all so far. It just annoys the hell out of me because i know that the sound wasnāt there before.
Well the only other things were these 2
Hmm yeah worth a shot swapping them out. I can hear it much better in the first video.
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You can calculate the motor current in BLDC mode via:
(V_voltage_pulse_width_modulated - V_back_emf_voltage) / R_resistance_winding_ohms = I_motor current
Through a quirk of physics:
V_back_emf_voltage / V_voltage_pulse_width_modulated = E_electrical_to_mechanical_conversion_efficiency_instantaneous_%
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Anyone know how proportionate is the lifespan of a battery pack against different charge currents?
I have a 12s6p 30q. Was charging with a 4a charger.
Now Iām using an 8a one. Iād like to basically know how many cycles I can go before seeing a change
Itās on the 30q spec sheet expect slightly worse results for anything greater and slightly better
for anything less
Thatās a discharge cycle spreadsheetā¦
Doesnāt help me much with calculating differences in cycle count when theres a change in charging currents for the same specāed pack
4A charge on there as well is what theyāre tested at
Iām trying to say itāll maybe extend the life a bit charging lower but 4A per cell is what theyāre tested at so, your fine might squeeze a tiny bit by always charging lower buts itās negligible imo
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On my phoneā¦was too small for me to seeā¦
Is doubling that charge equal to half the cycles? Or is there more to it?
More too it haha itās a 22A 70 degree cut off vs 15A discharge.
But 4Amps is within spec for a single 18650 so a 6 p pack is good for 24 the difference between 4 and 8 is minimal.
Doesnāt feel minimal with the speed at which I just saw my pack charge to full 
Haha fast charge for 30Qās is under an hour which means any 30Q pack can be charged in under and hour lol but yeah 4amps is like minimum for a 4p pack for faster charging 1-1.5 Amps per cell in p group is what I aim for
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So I guess Iām fussing about nothing then. No way in hell Iād have the budget for an 18+amp charger
Iād rather put that into a new pack
Edit: just found out monster chargers exist
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Do we have someone from https://diyelectricskateboard.com/ here? I need to know if they repair shorted TB ESCs and how long it takes
You mean swapping the bearings or the belts? ^^
Bearings. But while youāre there check your belts out for any rocks stuck in the teeth or signs of damage.
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