TLDR: Seeking optimal/lightest setup for a 4wd eskate with enough torque for steep hills and decent range without the battery.
Current plan: Dual battery setup with 2 separate enclosures, as much range as I can pack into my enclosures with adequate torque for climbing steep hills. Custom battery builders please contact me.
2 sets of 2 6354 Motors, 140kv for torque
2 Flipsky mini 6.6 or Tenka 140A capable ESC’s for running the 6354’s at 60A each.
2 receivers, one remote, i.e torque boards mini remote or make my own gt2b mod. Alternatively canbus line with puck or vx4.
Questions:
If I want a light setup for mountain bike trails with adequate power not excessive or thrilling and maximum range, would you recommend downsizing the motors to 50**'s with less current, 12sLessP or 10sMoreP, some other option, what is optimal here? Want to be able to climb steep hills, not worried about top speed, some range would be nice, lightweight top priority.
Anyone have a dual receiver setup they like? Or will I end up running canbus.
If I end up running canbus, is there an advantage to wiring packs together in parallell or series since I’d have to accomodate wires between enclosures anyway? Wouldn’t the max voltage/power stay the same even if I wired them together still same number of motors drawing from same number of cells in the same volume regardless of how I wire. I.e 2 packs of 6s4p wired in series for 12s4p outputting to both ESC’s is the same as having 12s2p packs each wired independently to one ESC.
The non TLDR post, with full context and detail as of 2/21/2023
Hey ESK8 wizards, I am excited to be making my first forum post. I got into this whole mess by buying an Evolve GTX at police auction on a whim and buying Ebay velcro footstraps to it and hitting the mountain bike trails here in Ventura county CA. Since destroying that board, I have been developing mechanical innovations for an e-mountainboard for some time now and am getting ready to purchase electronics for the build. I look forward to sharing more info about the mechanical aspects of the build once it is complete.
Design constraints around the deck of this board necessitate having two separate battery packs and separate enclosures for each battery and ESC. It would be extremely inconvenient, and compromise novel mechanical features of the build to run CANBUS or Split PPM between VESC’s or parallel/series connections between the independent batteries. So the only connection between the front and rear drives is ideally the remote receivers.
Therefore I am pursuing a dual receiver 4wd setup with independent PACK->DualVESC->Motors arrangements for each truck communicating with a single remote over two independent remote receivers.
I have spent a few days pouring over the forums now learning about all the components available for this build and trying to optimize the board for torque and range while minimizing weight. It is essential for this board to be as light as possible.
The order of priorities for selecting components and battery size is:
- Low weight, 2. High torque output relative to motor size, and 3. Range in that order. The emphasis on weight is because I want to ride this board like I do my mountain bike. Steep climbs and descents, technical terrain, and fast turns. I don’t have any need to go very fast on the street and want the lightest setup possible, so a high top speed is completely irrelevant and I only want as much power as is needed to maintain a relatively low speed on technical climbs. Therefore I can run a smaller motor with a torquey gear ration to acheive what I need without a lot of battery. I wouldn’t mind topping out around 20ish mph, could be nice to go a bit faster. Honestly, the electronics are mainly there to act as brakes, acceleration/torque are not important beyond the ability to climb steep hills. Gravity will be plenty thrilling on most trails as long as the board can get you to the top. With that said, I will pay for as much power as I can achieve with the minimal weight possible. The motors should be right around a pound maximum, or 550g or less. This basically limits the volume of the motor to something like a 6354’s. Regarding components, I am not that worried about who makes them. Flispky, Radium, and even MassiveStator can all take my money regardless of opinions about the component’s reliability or customer service if the component fulfills my requirements efficiently. I am trying to save every gram I can, in relation to the electronic components this means I basically don’t want to be oversized or bottlenecked anywhere. Space is constrained for mounting ESCs and batteries.
Under each foot for this deck will be an enclosure of around 25020040. I need to fit the batteries in there, preferably the ESC could sneak in there too but if not I can shove that elsewhere on the deck, but I’d prefer a setup with it all in that enclosure. Dimensions are subtly flexible for those enclosures. This is the primary reason I am looking at the potentially unreliable FLIPSKY DUAL Mini FSESC6.7 as its largest dimension is 80mm and can handle the requirements for this build. Next I’d look at the TENKA by focbox as its pretty small too and has built-in switches etc and for its sale price of 200 right now seems unbeatable. If I end up needing more power I’ll go with the MakerXtech line but I don’t see them being the best choice for this build yet. Maybe if I end up with a high gear ratio low kv motor, 45amps max and smaller battery I can go for VESC 4 then MakerX makes more sense.
I would love to know how others would spec this board given these design prompts and if anyone can help me figure out whether or not it would prove more powerful/efficient to wire the packs together and control via canbus instead of dual receiver and independent pack setup. Sorry for the super long post, I will add a slightly shortened version at the top.
I have a full composites workshop equipped with resin infusion setups, a high temperature 3d printer, and proficiency in CAD to aid me with making enclosures and other novel parts for this build like pulleys etc.