Go radical with this one. Steve McQueen was right blowing Taylor Street in San Fran almost 50 years ago…
Hey, may I ask you a question ?! 
Since you are using 4wd hubs, which I intend to do as well I got a few questions for you If you would endulge me.
So first what KV should I get, planning on 4 hummies with custom KV and I am fairly light with only 80-85KG/175LBS. The focus would be on speed, (responsible about that, seasoned downhill rider with plenty experience with speed I won’t ever hit with ann esk8 and proper protective gear / leathers) but since I will be using focboxes I am limited by the max RPM. Was thinking 120kv on 90mm with a 12s5p samsung 30q as a battery. Don’t think I should be going higher with the kv since I do live in switzerland with many many hills all over. But mayby 4wd is so different that a higher KV could be possible but still the RPM limit would hit in before I max the higher KV out ?! THought mayby your experience may seem something wrong with this plan
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I know I’m not @BigBoyToys lol, but most likely you won’t have to worry about hitting your erpm limit with hubs as even with 12s and 120kv your erpm would be 42k at a full charge with no sag, which is way below the limit of 60k.
Plan sounds good to me, Id suggest going with the lowest KV that will support your top speed requirements. 120kv and 90mm will probably break 40mph pretty easy. Is that what u are looking to do?
So is their no category for 4wd in the next performance day? I don’t have anything less to bring.
BTW, my ankles healing well. Did a test ride yesterday and it felt good. Might be able to still make it
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Well honestly, I would like to max out the build speed wise. Meaning as long as I am under 60k mayby like 55k and the higher KV still makes the board reasonably decent at cruising and inclines. Basically I am pretty sure that 40mph with 4wd and a 12s5p or 6p should be doable. Everything above is new teritory for me and I haven’t found much information. If I would end upt with a set up that is super quick but would limit the range to 5-8 miles I wouldn’t want to sacrifice usability over speed.
Basically it should be more of a racing set upt for closed of streeets during events, around our airport with a dedicated inline/skateboard route or as a filming tool for raw runs.
I know we are generally hesitant with poeple wanting to go 50mph or more, but first of all I would not want to be riding around town like a maniac. I have actually a need for an esk8 that fast. IT would allow me to film raw runs of friends (normal downhill) and the ability to accelerate and deacelerate would mean I could get the perfect footage. And most runs we have in switzerland aren’t that fast to be honest but you hit 45-55 on most of them (of course you can hit alot more on different routes and with increasing the risk you want to take). Anything faster has to be done with a car anyways.
TLDR: what is the highest KV you would recommend for a 85kg/190Lbs guy on 12s6p. Still somewhat decent range, some hill climb potential.
Ive heard there can be some issues when running very high KV’s on the VESC 4.12 hardware when it comes to motor detection, startup control and high speed rotor position tracking. Since most of my personal experieice comes from low KV motors (60-192kv) I can’t comment on those issues 1st hand. Thats partly why I recommemded the lower KV. Are u willing to invest in VESC 6’s? If so you SHOULD have much more wiggle room to use a higher KV motor.
Definitely not much info available for belt setups above 40mph and higher KV’ on the VESC. You’ll be using your’s and our best estimates and advice to build what hasnt been built by many if any.
Using the lowest KV that will meey your speed requirement will keep the motor as cool as possible (probably still gonna be hot) and maximize your braking force. A big battery and BMS are needed to not just to supply the acceleration power but also to accept all the braking current that will be regenerated at high speeds.
I still suggest low to mid 200’s for KV if using a 4.12 VESC and then adjusting the gear ratio to dial speed and braking with the available current supply and intake abilities of your set up.
Alright, Well I will be usinng hummies hubs (so no gears to play with), I think I will go with 140 to 155Kv.
Sadly Vesc 6 is not an option for me, since this build is already a big strain on my wallet as a student. Vesc 6 would blow it out of my budget.
I will read up further on possible BMS options for such an endevour as well as wiring for quad vesc’s.
Thank you for your input and help. I gues I will open a build thread as soon as parts are roling in in a few weeks/months. I desperately want to take it to the next level in my DIY line up.
Opps, Sorry Ive been in Hawaii the last week and misssed that you decided on using Hummies motors. I have a 4wd hummie build in my line up and trying to decide on KV as well lol. I have 149KV Carvon V2’s on 90mm wheels and have hit 49mph but they free rev to just under 70mph I just need more amps to get to a higher speed. I broke 40mph with with 2 different 130KV, 90mm wheel, hub motors as well. You are in the right ball park for your KV at 140ish. Youll need lots of power though. 18650’s arent gonna cut it unless your at least 6P imo. Id suggest LIPO or better yet 26650 A123 so you can accept the higher regen currents with less concern.
Unless hummie switches to a higher pole count motor I dont think eRPM is much of a concern.
Alright , I see you stay true with your 4wd builds. Wanted to go carvon 4wd first, but decided for the hummies since I already have a carvon board.
Guess I also will hit a little more speed since I am a lot lighter than you and used to speed tuck anyway. Are you going the 18650 route for your 4wd hummie or 266650 ? I am so intrested in the a123, but kinda hesitant to build my own battery pack for a 4wd build, since it will be at its maximum.
Have to check what both options would cost premade and if I did it myself. If the difference is to big might have to solder that thing on my own…
Happy I am not the only one working on a hummie 4wd, let me know what KV you are going with
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Agreed, your weight and lower wind resistance will definately get you to a higher speed.
Soldering the A123 was pretty challenging doing end to end style. If you have room for a bunch of 10AWG wire Id go that route but 3P would probably be the biggest you could fit and that isnt enough capacity or power for my likes.
If you go 30Q 6P youd probably be fine. I still see massive sag at under full load though. Over 6V usually.
I have a few different battery options on hand, but either 18AH 25C lipos or my 14S4P A123 pack, depending on what I end up deciding to use the hummie build for.
14s, damn son. Yeah well 10s6p is already huge, have a friend who has done a few a123 packs. Will talk with him and decide… Both options are expennsive anyway… sick of studenlife man 
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Yeah, well since higher voltages are the best way to make the most of the available Amps I stick high voltage packs.
Definitely expensive, I could have bought a used car or two with the cash Ive sunk in batteries this far hahaha.
The total whr for even a big A123 pack is pretty lame imo though, probabky only appropriate for a a higher powered high speed build that needs high regen currents. Seems double the range could be acheived with 30Q’s for the same amount of space.
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If you want a larger 30Q pack welded with copper pads to minimize your losses in wires, I could help out. I got a CNC welder from sunstone that can do up to .02in thick copper.
I recently built an 16S6P pack that can do 120A continuous sagging less than 5V. It requires 8awg wire.
That’s the beast. I don’t have any pics of a build that arent work related right now, but can show you something on Monday
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Wow, thats awesome! I will definitely consider you when it comes time for my next big battery build.
6 days to SPD2 Stock Production Single Motor, Stock Production Dual, Custom Single, Custom Dual, Custom Quad, Open Class.
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Lookin sweet AF Moe-Bro 
trophies and all… did not see that coming 
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How bout a trophy for the figure-8 course? The rest is a test of torque and rider weight and think your gunna take all the trophies!
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