Can’t wait to see you riding this beast!!!
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HEY DUDES!!! So I’m slowly making progress - heaps of house renovations + a 2 year old have kept me very busy. No video footage yet as my gopro died (I’ll get a new one very soon) and I need to get my setup running properly before I go too crazy! 
I have a quick question for all you 12s emtb crazy fools running VESC or FOCBOX. I’ve installed the new @Ackmaniac firmware/tool and it’s awesome. The only problem is i have unsensored motors (sk3 6374 168kv) and in BLDC it cogs like a mother fucker. However once I’m going the power, response everything is exactly what I want. But I’m jumping into runs like a snowbaord which is gonna be a real pain in the ass if i stall at the bottom of a jump or bail on an uphill slope.
So I switched to FOC and it ran beautifully. Start up was smooth (zero cogging and heaps of boost), and it felt very similar to BLDC when running. The problem is it cuts out at high speed or when I tried to accelerate too hard and feels very dodgy - it just cuts out. I’ve only taken it out once like this (as it’s pretty dangerous) and when I got back (3km ride) the FOCBOXes and motors were RED HOT! Like stupidly hot, so I’m guessing FOC on 12s without cooling could be my issue?
Is there a compromise with the motors/ESCs I have? I’ve tried increasing the start up boost in BLDC but still get the jitters. With the correct cooling could FOC work for me? I’m pushing it pretty hard with 80/80 battery/motor max and absolute max at 155 so I could lower it but I really want all the power I can get!
Any help would be hugely appreciated and I swear once I have this running correctly I’ll record some nice fat jumps and spins for you guys! 
Post Screenshots of your settings. Add passive aluminium heatsinks (best for heattransfer with air) to the FOCBOX. Add hall sensors to the Motors for a nice startup. FOC creates less heat than BLDC because it is more efficient. And you have to be aware that a offroad build with pneumatics needs roughly double the power than a street setup.
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Thank for the super fast reply @Ackmaniac.
I was thinking heatsinks would be a good idea anyways, adding hall sensors might be a bit above my paygrade though! 
Intersting that it shouldn’t get as hot as BLDC…
Here are my motor/foc settings:
I have to say I’m totally new to FOC so I mostly used the default settings once I had run the motor detection so hopefully you’ll spot something obviously I can tweak?
I really appreciate your help - thanks.
Looks good in Theory. Now some fine adjustment. You said that you get issues at high speeds. Try to set the Swiching Frequency in FOC->Advanced to 30 khz (default 20 khz but i always run at 30 khz) And i also good better results by increasing the observer gain at minimum duty to 50% (but that’s more important for low speed) Add a bluetooth module and use may app then it will be easier to analyse what is going on. Especially because it logs the errors.
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Thanks - really appreciate the support. I’ll order a couple of Bluetooth modules (FOCBOXs are over split ppm) and grab the app. I guess I can take my coulometer out now which will leave space for the aluminum heatsink - the shunt on that thing is 100a and HUGE! I’ll let you know how I get on.
Btw…I just looked over the screenshots and realised I haven’t changed the ‘additional info’ settings, i.e. pulley teeth, wheel size etc - am i right in thinking this screen is info only right and won’t make a difference? I’ll put the right details in anyway but just need to check as that would make a huge difference if it takes that into account!!! 
Thanks again,
Dan
WOW - the increase from 20khz to 30khz seems to have done the trick!!! It’s pretty late here so I only did a couple of test laps but it has the punch back and no drop out! Woohoo!!! I ran it with the enclosure (Ultrabox 206) open and everything stayed nice and cool too - so I defo need cooling!
What are people’s recommendations when it comes to further cooling FOCBOXs or any ESC in an enclosure for that matter? Should I mount them with Thermal paste to an alu sheet and have it exposed (but sealed) popping out of the lid so it get’s direct airflow, or would a fan work better and be less messy?
Super grateful for any feedback - I’m so close now to letting rip on this wild thang!!
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Just try it first with a closed enclosure. Because you mentioned that your motors got hot as well. So i guess the 30khz helps already with that because it detects the actual position of the motor faster and more precise and by that it runs also more efficient. When it comes to assisted cooling then i think a external passive aluminium heatsink make a huge difference.
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Yeah very good point - I’ll do some more testing over the weekend and see how it goes. I’d be blown away if this small change does make all the difference because I did a couple of kms tonight on my test runs and it was totally cool so you never know! Thanks again for the immediate reply - you’re a true gent! 
WORD UP HOMIES!
So the testing/riding has been slowed down by a few small technical bits and pieces and I also had a massive stack going way too quick and fell jumping a speed bump in the road and fractured my pelvis (oops - and that was wearing full pads!) - but I finally got out today and found a small dirt track to play on.
I’ll edit the vids over the weekend and post them but here’s a few stills in the meantime!
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Brother i´m REALLY happy to see you performing such nice jumps…the Boardgrap looks amazing!
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Thanks bro It’s due to your amazing drivetrain that this is possible! Plus your commitment to pushing the boundaries.
I’ve been desperate to get out and ride for sooooo long!! Watch this space 
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Wooohooo!!! Flying Dan!!! Can’t wait to see more. Hope everything is running fine, finally…
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Sick pic mate !!! Cool youre back on ride so fast !
The playground look so big and funny, ENJOY
hurry to see the video now 
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Yeah man I love getting airborne! Board is running really nice now - still need to upgrade my motors to sensored but hey, it’s rideable! :)
How are your boards going? Any new builds happening - love seeing your innovation!
Hahaha thanks @Riako! Yeah I live to go big! As soon as I’m properly healed I’ll be looking for some bigger jumps. I’m not a mountainboarder (yet!) though so It’s good to take things a bit slower and build up my skill level.
How’s your riding going? Still loving the Vapor? It’s been cool to watch the evolution of that board!
The vid should be up soon - it’s just taking FOREVER to publish to YouTube 
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That are some serious pics, look great!
Can’t wait to watch the video 
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Well, after waiting 2 hours for it to upload to YouTube it’s up! Apologies for the crap audio!
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Whoa 
Nice man! How heavy is Your set up?
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Ah she’s pretty heavy - about 32.5lbs at the moment! Feels lighter the faster you go though!
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