Thank you for the info. It looks a bit risky for me to go this route at this time because i am still in my larve phase of battery knowledge.
What i am hoping to do is use my multi port 6s charger to go group by group.
So i will need to make two 2.0 - 2.54 jst and plug them into two of the balance ports. Where i get unsure is where i pull my negative line from? Should i gator clip to jst? It shouldnt matter which pgroup since all the negatives are on the same line right? But then is the voltage too high for my charger and that goes popfizzle melted moneyâŚ
So Iâve been running my lipos to 37.40V cutoff start and 37.20v cutoff end, I was curious if I could drop them a little lower, 36V to be exact so I can squeeze some more range out of them or will that risk shortening their lifespan, Iâm trying to keep them in good shape as long as I can
For myself and anyone who may have an outdated gear drive, a la 3ds, if i purchase a 3d printer can i just print replacement gears? Do i need something to get dimensions or make/scan the gear in/into the software? Do these files exist already on thingiverse? I know nothing about, just trying to gauge whether it would be worth in the future?
I have another question I wanted to ask about my street build & trying to get max battery life - its a 12S 16Ah lipo setup & currently I have 205kv 6355 SKP motors on there with a 3.75 gear ratio - would I gain any efficiency / increased range on lower kv motors if everything else was the same (including going the same speeds/terrain)? There are 150kv motors of the SKP version but also Flipskys/Maytech in that size at other kv as well.
Lowering kv but keeping gearing the same will make very little difference to efficiency. Your top speed will be lower and it will take fewer amps but more volts through the motors and vesc for the same effect.
Youâd need to 100% accurately remodel the gears in the first place, thatâs something most people donât know how to do. Scanning isnât an option, itâs not precise enough.
Also yeah, standard FDM 3d printed gears really wouldnât last. The point where it even starts to makes sense to try is engineering grade filaments, which needs to be taken into account in printer selection. Even then, I doubt youâd get much life out of those gears.
If you do have an accurate model though, an option is getting SLM 3D printed ones from steel, those do seem to perform good. If youâd install them in a drive that used plastic gears though, theyâd be very loud. Drives designed for steel have smaller teeth which really changes how they sound.
SLM printing is only possible in industry, not something youâd setup at home and printers are very expensive.
If you lower kv AND change gearing for the same top speed, youâd gain efficiency. But this kind of efficiency gains are only for super chill rides. My record is averaging around 7 Wh/km
As soon as you start riding fast and accelerate hard, higher KV often ends up more efficient. If this is a chill board that you want to maximize range on, do it, if not, donât.
@CarelessAquarist@Dinnye thanks, those both make sense - I would say my speeds are chill, only up to 20mph ish, but a lot of pretty sharp hills changing up/down frequently + stop / start at signs & signals, so doing a fair amount of motor work even at chill speeds. Does that lean things to either side? I do have other motor pulleys that I could use to change gearing - wheels are locked at 45T
Just in case you didnât already know, higher kv and a larger gear ratio is able to make more torque for accelerating and low kv and faster gear ratios waste less energy spinning the motors.
*at very high torque the higher kv setup is more efficient, but we generally have most of our inefficiency in freespinning losses.
If your riding is mostly chill but sometimes hard accelerating and hills it might work to use the lowest kv and fastest gear ratio that will still manage the max burst power you want
Yes in hilly environments lower kv might not be as good. Higher KV is more efficient if you ask for torque.
I donât think the gains would be very substantial unless you are doing 12-15mph on flat ground.
Basically a motor heats up from 2 things, rotating at high rpm and creating torque. If you only chill on flat ground, you can run low kv and be more efficient by minimizing rpm. If you ride aggressive or on hilly terrain, higher kv is more efficient by minimizing losses from creating torque.
Great, yeah this helps my understanding more - as long as it wouldnât be some giant savings it makes me feel I can lock in my current motor setup on this one until it breaks. Trying to exit the tinkering phase on my builds where I keep all these extra parts at home to switch things up ha.
