a DRV8302 cold solder joint can’t be seen with the eye - not even with a loupe… also the DRV8302 is on the other side of the board. So is this a good known to be working, VESC ?
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thanks for the help, it shouldnt be the carbon fibre as everything is covered in heat shrink. the acceleration things happens when im already moving and accelerate more
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Short off topic thing. You about to cut your balance wire with the nickel here.
I would Route that balance wire a bit different.
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I dont know if it is known to be working as i havent been able to use it on another board. should i contact hobbyking as they have a 1 year warranty?
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thanks, i will change that 
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Well first you have to find out if it actually is the VESC… so try to run directly without BMS for a short test run… then contact hobbyking
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thx…this is a learning process for me as well.
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ok, will give that a go. thanks
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me too. its a pretty steep learning curve.
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especially when things dont work 
Also if you feel like experimenting you could build a small “street” simulation and get something to hold back the wheel while accelerating with the remote inside your house and have the VESC Tool log the activity (if you have a bluetooth module its quite easy - otherwise connect USB)
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indeed…I’m reading for an hour + a day on this site. It’s a lot to learn sorta addictive in a way.
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great idea. thanks. i dont want to stop the motor from spinning but just slow it down right?
You just want to build something that simulates the “street” friction… maybe build a small setup or carefully have a longer piece of wood to create friction… I once used two unused trucks with wheels and a small break to simulate a road on my first build… get creative but be careful that you don’t hurt yourself… those motors got power
great. thanks a lot 
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No, if it´s a bad or unbalanced P group the BMS will cut power whenever that P group reaches 2.8V. That would explain why your capacity meter drops so dramatically. In my case the BMS cut the power at 50% or roughly 36V. 4 of my 5 P groups where at 3.8V and one group at 2.8. Just try to take measurings of your P groups at the JST balance wire cnnector of your BMS. There are plenty of videos on youtube how to do that.
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Just as you replied I figured out the problem and you are correct. I couple of weeks ago, while not riding, my vesc would not turn on because my BMS kept cutting out. I found out that I had an unbalanced cell. I charged the board and they were all balanced but the cell must’ve become unbalanced again. I think that is the problem I’m facing.
So I need to replace the faulty group of cells and replace them with some new ones right.???
Thanks for your help
Your BMS can only balance a certain amount of difference, if your cell drifted beyond that you need to charge the P group individually. Does your capacity meter shows 42V at the end of charge? You only need to replace the P group if they are dead already. You can replace the P group if your cells are not too old.
it shows 42v when fully charged but they seem to discharge more and become unbalanced
I’ve just wired in some new batteries. Before I wired them in they were at 3.6V. I put the pack on charge but the new cells remained at 3.6v and all the others were balanced to 4.2V. do you think it is an issue with teh BMS?