Does this count as a failsafe?
Haha. But no, I did not program a failsafe. Would you be referring to the GT2B’s failsafe or one programmed in the VESC? I remember reading/see both but used neither. Which method is preferred?
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Exactly why it’s mandatory to learn some longboard skills. Glad to hear you’re alright. The difference of a couple of seconds and it may have been a different story. Set up that receiver fail-safe.
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With gt2b it’s simple. First you want to setup ppm tab correctly. Make sure pulsewidth values correspond to 0% 50% 100%. Most important being 50% at neutral. You can adjust this with throttle trim on remote.
When you have that setup properly all you need to do to set failsafe is press and hold a little button on the receiver that is marked and look lights should flash. To test it worked you can check in the ppm tab the green bar (check box “display”) should stay at 50% when remote is turned off. You can turn on/off controller before rides to make sure failsafe is working also.
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Hah i see, live and learn
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surely teach us how to slide 75a wheels! jk. I don’t think I have a fail safe so when my remote ran out of battery I kept going, but due to lack of skill and great amount of crashing experience I went off road and flew into the bush. now I always charge my remote.
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Yes please tell us how u slide such wheels
Go fast and commit. Any wheel will slide at 20mph+. (Having a runaway electric board will solve both these problems!)
The heelside shutdown slide is very easy to learn, since its only half of the Coleman slide (aka heelside pendulum). [Note: There are countless Youtube videos available for this slide. Many years ago I wrote up a very thorough “how-to” for a technical writing class; maybe i’ll share it when I have time]
I recommend this slide for e-skate because it’s simple, safe, and you only need one slide glove. Wear a slide puck on your front glove and hold the remote in your rear hand. Even if you screw up this slide, it still puts you in a very safe position to fall; it lowers your center of gravity (no impact) and you’ll just end up sliding to a stop on your hands/feet if you lose your board
Flywheels slide very well once properly broken in. 81a is ideal, but 75a is very doable… it just kills your wheels faster and has a stronger hookup. Don’t attempt to slide fresh Flywheels (especially on smooth grippy pavement) without breaking them in, or they are prone to chunking. Note that sliding your wheels inherently makes them much less grippy (which is why I only slide my e-skate during an emergency)
I recommend learning the basics on harder wheels, perhaps even on a doublekick setup. You’d be better off using something other than your nice e-skate wheels because you are almost guaranteed to flatspot your wheels when learning (pro tip: don’t lock your board at 90°. You need to keep the wheels moving throughout the slide). Once you’ve got the body mechanics down, the skills are transferrable to any board
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Thank you for this!
Can you explain more how the GT2B failsafe works? Does it define a set value if connection is lost (i.e., 50%=neutral)? Or does it apply a braking current of some sort?
I never set up the failsafe because I didn’t want the board to apply brakes if the remote is shutoff. I sometimes ride with the board powered on and the remote off. I also tow my board around by the front truck (once again, while powered on to prevent blowing the VESC)
. . . .
This is a good idea. You’d want the button to be in a place where it doesn’t break your stance and compromise stability. On the heelside rail behind the front foot would be an ideal location
Though in the few seconds while stuck on “insano mode” speeding toward the red light, the last thing I thought about was turning off the board or receiver. Maybe that’s just old DH habits kicking in…
Failsafe means that when signal is lost it will return to neutral/50%.
Turn on your board and remote. Then turn off remote to see if there is any movement. You can also check in ppm tab
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The fail safe will give the esc what ever signal your remote was giving when you set the fail safe. Say you press the fail safe button at 100% throttle for some crazy reason, then if you loose connection the board will go to 100% throttle. Its recommended to set it at neutral for obvious reasons.
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If you make any adjustments in the PPM tab then you have to reset your fail safe or it wont be at neutral anymore.
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Another thing I have found with the GT2B if I turn on my board but not the remote after a minute or so it goes to full throttle. Not sure why. But if I turn on my remote, then turn it off again it sets the fail safe correctly and I can leave my board on and remote off without any strange throttling. So now I always turn the remote on first before the board just to be sure.
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Keeping the remote fully charged is also important. When the battery gets low it still works but the trims move around which can make the board act strangely.
A correctly set and tested fail safe is one of the most critical safety measures. I have had the GT2B drop out going over tram tracks but due to the fail safe being neutral it just cut the power temporarily, and the connection comes back quickly on GT2B so it was all good.
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Had the same “full throttle” thing happen to me! Was a bad connection, the reciever to vesc cable…just replaced it. Also as mentioned adjust your throttle trim to the correct point, iv found if you have it set at too much throttle and not enough brake even the slightest movement on throttle turns in to way too much throttle and just continues to gain speed. There’s a sweet spot your know when you’ve found it. On my master cho moded gt2b it’s with the arrow pointed between 12 and 1o’clock.
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@jmasta great write up and story! Makes me want to improve my slide skills. I’m not sure I would have reacted as well. I think I would have tried foot braking and then rolled off to a knee slide (I wear knee pads).
In all my esk8 riding I’ve never had a signal drop or error w GT2B. I set failsafe, so I wonder if I’ve ever had a drop and not noticed.
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Haha they may slide like soap, but that is UHMW-PE. Vintage 2009. 
Lightweight, low coefficient of friction, and nearly bulletproof. That’s not even an exaggeration… NASA uses the same material for radiation shielding
Thanks! To be honest, at speeds above ~20mph, I am much more confident sliding. That may be because when footbraking, I always pivot my front foot so it’s parallel with the board. The guys I know that footbrake at 50mph tend to keep their front foot in position
And now that I think about it… I don’t know if I could overpower that SK3-6374 motor stuck at max throttle, with just the sole of my shoe. That motor is powerful
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“Loopkey acessible from topside” I liked this idea so I added one to my board. With this design I can access from both sides.
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Great thinking. I’m going on/off switch and planned to mount it on the side of my enclosure towards the back for easy accessibility in a pinch. I think I’ll add some sort of marking on my grip tape so I’ll know exactly where to reach for if I ever need to.
I set up the fail safe on my gt2b to coast when connection is lost with the remote, this works fine as when I turn off the remote whilst holding the throttle, the motors stop spinning after 1 second. However, if I leave the remote off and the board on for some time (im guessing 1-2 minutes) all of a sudden the motors will start to spin again?! This almost caught me off guard one time on a dock, luckily the board was upside down (phew).
Has anyone experienced the same issue? Is there a way to fix this?
tip eat a potato
Daaang, that’s some scary stuff! That’s why I intend to be very careful with the failsafe code on my custom Arduino-based receiver. I want it to cut to neutral throttle if anything at all disconnects. After reading this thread I realise it’ll be a good idea to also have a manual safety switch or loopkey (that physically disconnects the battery) on the side of the board as a backup to the software failsafe. I’m no stranger to speed (I rollerblade at some pretty high speeds sometimes and thoroughly enjoy it) but I see no reason to make that speed any more dangerous than it already is. I’m happy to go flying through a rough gravel patch or bounce off a speed bump at high speed on my blades but if I can’t see if a car is about to appear from around a corner there’s no way in hell I’m going down that hill.
But I guess most people would have a similar opinion.
Very similar thing happened to me with an identical set-up:
VESC v4.12 (2.18 firmware) FS-GT2B Remote (stock) SK3-6374 149kV @ 12S 14:27 gearing on 69mm wheels
I inevitably rode over a metal plate that was spanning across a bridge. The impact (similar to riding over a larger crack in the ground) caused my board to stop responding to my transmitter. I turned it off then back on; board was riding fine again. I approached a second bridge with another metal plate spanning across it. This time I rode over it at a lower speed to minimize the impact. The board reacted the opposite way… it went full throttle and wouldn’t stop.
I did have the timeout feature on my VESC set to 1 second, but that didn’t seem to kick in. I was unaware of a “fail safe” feature on the GT2B. Good to know!
People on this site have been telling me that the cable between the VESC and receiver got loose which caused my board to go rogue.
Glad to know you’re okay!