The Hyena EMTB | Trampa 35 short | Dual SK3 6374 | 2 x FVT 120a HV | 8S/12S lipo | DIY mounts | DIY controller

Lolx, sad for a few hour and start research again. FVT can refer my reply from other thread.

Cheer and Chill mate~~

Thanks! So Sleeping Lions work reliably on 12s. How do you program them? Do they have usb port or need extra programmer? Also where did you buy them?

Ask this in the other thread too maybe, there is a dedicated thread about.

Thanks. Iā€™ve contacted FVT, gonna order them lions.

Iā€™m starting to have second thoughts about the batery iā€™ve soldered Cause iā€™ve used a bunch of 4s batteries it turned out a horrible mess of wires. Iā€™ve used acid flux to solder aluminium and nickel, and then neutralized it with soda, so it looks extra ugly. It seems to be fine for now, and single port charging works, just worrying about some wires breaking off or cells going bad and killing whole thing in the future.

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That looks scary to meā€¦ If it works maybe secure everything with hot glue then shrink wrap it.

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I agreeā€¦ i would isolate these connectionsā€¦ if one wire breaks looseā€¦ it might touch things it usually shouldnt touch lol

Of course it was hot glued and taped all over, i opened it to add extra balance plugs for voltage checking. Iā€™ll probably take it apart into 4x6s batteries, with their own connectors. If i place escs outside the box, thereā€™s enough space for wire harness. Anyway soldering a lipo is so much stress, never want to do that again :expressionless:

Iā€™m a little spooked after one of my quadcopter batteries almost burned during charging recently. The voltage on 2 cells out of 4 froze at 4.0 and it got hot, good thing iā€™ve noticed it.

Some updates.

Took the battery apart into 6 x 4S. This way i can alternate between 8s/12s using different wire harness. For now running 8S 15Ah

Been using FVT 120a for a couple of weeks now. They arrived in different colors, and one of the capacitors was dented. I opened the esc to check if the cap was shorted, cap was fine, but some other components were pre-burned inside, and itā€™s before i even powered it: Surprisingly ESC still works, though it frequently loses sync if i spin it without load.

Second ESC works alright, though BEC failed soon after installation, gives 0 volts on red wire. Powering everyhting from first ESC.

I have mixed feelings about these ESCs. They are very powerful, can handle lots of amps, and with a small fan they stay completely cool no matter the load. They can go full power from standstill, and do a sick wheelie (later about that). Can startup uphill in sensorless mode, can startup rolling backwards. I like duty cycle control a lot more than vescs current control. Works a lot better offroad, on vescs speed offroad drops significantly, while these escs donā€™t care about the type of the road. And also iā€™m using expo (x^1.5) on the throttle, feels great.

Brakes are a little tricky, the curve is very steep, i had to trim the PWM output to the spot before they completely block the wheels. I can still access full brakes if i press the button on the controller. Already got used to them.

What i donā€™t like about them: sometimes after braking they go crazy and apply full throttle from standstill. You never know when the board is gonna do a wheelie. Happens 1-2 times a ride, usually goes away on itā€™s own or i have to reboot. Also rarely they go into some protection mode(?) and limit speed to 10-20% for a few seconds. Happens after sudden wheelies or hard bumps (less than once a ride). Also on 12s it happens a lot more frequently, and sometimes they loose sync under load on 12s, so for now still running 8s.

Added some extra caps, startups feel better now, though glitches persist Esc box is water-resistant, got into a rain once, the box was dry inside. The escs are hot-glued to the lid.

Switched to MT60 connectors, theyā€™re pretty good Also changed all the crappy zinc plated screws to fancy hardened-steel hex screws.

Ready for the night ride

I need stronger pulleys now

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Oh and some video. Rode my board to the motocross spot, but because of constant rains the track is all overgrown, oh well

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Oh btw, pulleys can be easily fixed with styrofoam+acetone mix holds up pretty well Also initially i wiped them with acetone. They break when i land on the pulley itself, like rolling over rocky terrain or a broken curb.

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Had 2 pretty bad falls in one day, next day got a cold, didnā€™t ride for 2 weeks. Iā€™m back.

Swag from @trampa No more rattling for now

And new pulleys from @idea: 3mm walls, just tested them, work fine :+1:

Hereā€™s the model if anyone needs it, original was made by a friend of mine, this one is modified by me: https://dl.dropbox.com/s/tiymrytcc12uycg/Pulley_HTD-5mm_75_tooth_width_15mm_V3_2.stl

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Have you looked at the new firmware for the escs it is meant to fix lots of the issues your having with them

Iā€™m using Mountain skateboard_120A (5-12S) _ singleDrive _170818 from here http://www.szfvt.com/en/download-6.html I think it has less problems, though can still go crazy sometimes.

Ah ok. Maybe I was thinking of the firmware fix for the sleeping lion Esc

It is sleeping lion, they are very inconsistent with naming :smiley:

Oh wow now Iā€™m confusedšŸ˜‚ There was a thread on the problem and someone found firmware that fixed the issue

Found it scroll down to post 59 or 60 and the new firmware that someone found is there although you may already have this

Yea, i already have the latest firmware. Same problems, probably would work better with sensors. Iā€™m kinda used to riding without triggering sudden wheelies - just donā€™t let it freewheel and limit the brake.

Brakes are very dangerous on this thing at speed, can suddenly block and cause you to loose control. I still have bruises from a month ago.

The obvious lesson for me is - donā€™t ride at speeds beyond your skills.

So staying on 8s, also thinking of freeboard bindings. Couldnā€™t find them for a reasonable price though, official site asks $75 for the shipping.

Finally getting charging system working. 36v 180w power supply 36v CCCV DC-DC module (hah, just noticed, itā€™s listed as 32v, when i was buying it was 36v) First try - blown crappy caps

Replaced all the caps, real ones are quite bigger, charging at 5 amps: Quite pleased with the balancing.

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Hi, Just stumbled upon your post. The VESC is not recommended to run on 12S, there are many known issues about this before you. Simply does not hold for that voltage. Bummer you had to find out by plugging them in.

I recommend searching benjamins forums in the future, board looks great tho!

//Linus