Yeah That is a killer combo
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I may very well be putting my Roxxys up for sale here soon if you’re interested. They’ve already been upgraded with cap banks too. The brakes are very touchy tho. Only have about 7 miles on them so far. Going to give them a couple more tries and see if I can get the hang of it, but there’s some big hills here and I rely on the brakes a great deal.
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Thanks @benjammin for the potential offer - keep me posted. I gotta say though I was tempted by the FVTs a while back too but chickened out so may just bite the bullet with them this time - especially as I could get 2 posted for less than $200 (AUD).
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Roxxys are powerfull but at the same time hard to controll, brake is really hard to control ! I got a pair of this MAytech Esc´s, flashed with other SW… never get on with it… maybe the FVT are better Max6 is still my worie free favorite, but of course with Topspeed Issues (-; 8S Actually are preparing one of my Roxxy Mtb with Vesc6…
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Ah hell yeah – can’t wait to see you ride a VESC6 monster!
I’m thinking the FVT have gotta be worth a go and @Kaly rates them so gotta be good! 
And…if I screw that up then I’ll go Max6!!
Aw man, i know that feel, i’ve fried my vescs after a month of riding then switched to FVT120a. They have some quality issues, but are very powerful, and with some tuning and extra caps i like them so far. The key is to trim brakes to 70-80%, trim throttle to 95%, and use some expo on the throttle (i use x^1.5).
Haven’t tried alternative firmware, i asked for default firmware but FVT guy didn’t give the FW to me 
So i guess i’m not gonna experiment.
Hi, so how do you trim brakes seperately? What remote do you use? I havent heard it is possible to trim these values in esc software (unless it would be vesc)… interested to hear.the story, im using mini remote and only whole signal - gas / brake can be trimmed.
I assume u might be.using gt2b? I know it has more knobs but still not sure about signal trimming on both ends, if u do it.in.hardware with electronics, please give some tips.as this.would be very useful
I’m using my own controller/receiver on arduino. I’ve never used gt2b, judging by the pictures it has 2 knobs for trimming. So first you do throttle calibration on the esc with full range signal, then you trim signal on your controller. To calibrate esc (same for 6s and HV versions):
Hey Dan,
according to your other thread you killed the CAN transceiver because the power connection of one FOCBOX was interrupted:
You should solder the power wires of the FOCBOXes directly together to the power wires ( Y Y ) so that they behave as if they were one controller. The servo input is a bit more tolerant to these faults but this would be the proper soluton. If you later feel like you would like to have traction control, you can solder new CAN transceivers and connect over can again.
What are your current limit settings? I started with 60A which gives good power but a quite smooth startup. I increased bit by bit and now I’m riding 100A motor/battery which gives the desired ‘grunty feeling’ … 
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Thanks @Duffman for the advice. So you mean red to red and black to black?
I’ve only ridden it once for about 2km before I returned home and blew my FOCBOXs. But I went hard right out of the gate with both set to 80A bat max. I’ll have a play with them more carefully though once it’s properly together - I was a bit reckless and impatient before and once I saw the wheels spin I just needed to take it out! Defo up for MAX GRUNT though!!! Be great if you could share your settings?
Yes, red to red and black to black.
There is nothing special about my settings. I’m running 100A motor max and 100A battery max. You should increase the absolute max to 155A if you get absolute overcurrent faults. Never above, as the VESC can only measure up to 160A and raising the value above this would in fact disable the protection. (I changed to 0,5 mOhm shunts which enables my VESCs to measure up to 320A so I set it to the highest progammable value, which is 240A)
You should increase the values only bit by bit, as I’m not sure how much the FOCBOX can take. If you’re looking for better startup performance from stand still you need hall sensors…
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Thanks 
Yeah I figured hall sensors might be my DIY venture as the pull from start up was quite weak before. I’ll give them a more thorough test raising in increments as you’ve mentioned and report back.
Do it the Jenso (@Nowind) way: Raise it till it makes boom and then rebuild it better and stronger and raise it further…
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Keep pushing till there’s smoke!! 
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Ok, FOCBOXs soldered up, I’ve simplified my wiring harness to remove surplus connectors and she’s spinning beautifully with the split Y PPM connector. Woohoo!! Now, before I hit the road, would you mind having a quick scan over my settings? This is how I had them set up before and the ride was very smooth, predicable, and esk8’y - if you know what I mean. Bloody lovely and I’d imagine perfect for a street carver but not for a dirt monster! So should I be looking to gradually increase Batt Max to 80a? Say in increments of 10a?
I’ll make sure everything is nicely sealed and vibration proof this time before I take her too far!
Thanks
Yes, for sure. As long as your battery is strong enough there is no reason to keep batt max lower than motor max.
If your FOCBOX survives 80A at low rpm it will also survive 80A at high rpm.
You could also raise batt min until you like the feeling of the brakes. Don’t worry about overcharging your lipos during braking as this happens only for fractions of seconds.
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Thank you for the fast reply - you’re a legend! Well in that case maybe best to set both motor max and batt max to 60a initially to see how it feels and just up to 70a, 80a (and beyond?) if it feels like it can handle it? Will heat be a problem for the FOCBOXs though? I’ll probably take the brake up to -20 too though they felt pretty good before but a little extra brake never hurt anyone!!
Ok, bench test with them both at 80a is great and you can tell the difference from 60a! Guess I’ll get her put back together properly and see how she feels on the road! Thanks again for your help - I’ll video my trip out!
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10 char
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