NESE modular jumper - 🐉 Dragon MTB build

Ah okay, I didn’t know what the power level of these lights was supposed to be tbh, if they run off usb I guess that’s fine

Looking at the buck converter again, it looks like it can only do 1.5a continuous, so as long as the voltage is set right you’re good

LED drivers can limit the current and voltage I believe.

Yep, I can’t find it now, but I believe the input voltage is 5-8.4V for the lights.
USB 2.0 supplies 0.5mA max, so x2 is ~1.0A. Safety factor of AliExpress, we can assume 2.0A is possible max current draw. Some of those Ali listings also sell a 2s 18650 pack for bikes, intended to be powered directly from the battery at 8.4V, so that checks out.

That’s how I sized the buck. It’s output voltage is adjustable, set to 5V now. Increasing that voltage may allow the light to run cooler (& the buck more efficiently). It can provide 1.5-3.0A.
Buck input voltage is claimed to be 55V (60V on some of the LM2596hv). That should be enough head room for a fully charged 12s pack.

I’ll do some testing, and try adjusting the voltage up to ~8.0V and see what changes.

@Toughook is running them at 8.4V, maybe he can chime in on performance so far.

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Nice nice. That’s cool

My lights I’m running at 7.5v each, I think they had a similar voltage range.

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Yes, so far so good with the 12v>8.4v buck converter. Lights running fine and as they would be expected to from the bundled 8.4v pack (which now sits in my drawer).

Longevity of the lights themselves remains to be seen, but they are not broken yet !

2 Likes

#Lights

A little more feedback on these lights.

I took them out for a night ride the other day. They have a high, low, and flash mode. On high, the pair are suuuuper bright. Like car hi-beams bright. It’s wonderful, if unnecessary. After a couple blocks, they shut down. Seems like an issue with my buck - it was burning hot inside the main enclosure. Too many amps, no heat sink. I’ll have to remedy that eventually. But the housings were at ambient temp - no appreciable temp increase at all.

I turned them back on onto the low setting, which is still quite bright. I ran that for about 8 miles continuously. Buck was very warm, but manageable. Headlight housing were barely warm at all.


Also… I ran into a (few) tree(s) out riding with @skate420 on some incredible single track mtb trails. I managed to crack my original headlight mount bracket in PETG: Files on printables.com

So I retooled it for TPU, set the headlights behind the hanger (duh) so they’d hit first, and stiffened the whole part. Also added a cable-tie hole for extra stability. Now they look awesome and survive anything. V1 is testing, but going strong.
Files on printables.com

[Street version in PETG on left, offroad version in TPU on right]



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#Tuning

After a couple longer rides, I’ve been hitting 30+ mph (48kph) consistently but it does not feel very stable. I was in a faster group ride (they come in chill, fast, and faster flavors around these parts) chasing some speed freaks on EUCs, lovely people, and barely surfing out the wobbles over cracks and bumps in the road.

I’m on a mission to get stable at top speed with this setup. The calc says max loaded speed is around 36mph (56 kph). I don’t think I’ve hit that, but I’m getting close.

Current setup:

  • Metal Matrix II trucks
  • Orange shock blocks front, red rear (used of unknown age, compressed / creep?)
  • Haero Bro - 30 deg tips, no wedges
  • 200x50 tires on (brand new) MBS fivestar hubs (yay!)
  • Some of the worst roads this side of New Orleans

Solutions to try:

  1. De-wedge the rear by 5 degrees (25R / 30 F)
  2. De-wedge the rear by 5 degrees AND wedge the front by 5 degrees (25R / 35F)
  3. New shock blocks all around (red rear, orange front)
  4. Increase preload on all shock blocks to max - see how it feels
  5. Try red blocks in the front
  6. Try orange blocks in the rear
  7. Skate more. Get better. Do ankle/calf/quad exercises every day for that iron grip.
  8. Find better roads
  9. Buy Matrix IIIs or Moon trucks
  10. Swap in the 6" tires and see what happens (still haven’t tried these yet)

While I wait for the PETG wedges to print, I’ll start with #4 - aggressive preload.

Thanks @Venom121212! as always

Super tough to get the calipers in there, but this looks to be about 2-2.25mm preload gap

Gave the loctite an hour to set and about to go for a test ride. :astronaut:

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Keep that weight on that front foot and it will help minimize this wobbles. Keep that rear foot stable and light on the pressure. It should act more like an oar/rudder at speed than an ankly foot.

I always picture myself like the silver surfer.

Keep your center of gravity over or even in front of the front trucks and it makes the board want to stay in line better… Like you’re dragging it behind you.

If it’s a well known bump for me, I press down on the deck a little bit right before I hit it so the up flex minimizes the cracks.

The bane of my existence is hitting a big bump while I’m in the middle of a moderate turn and it feels like the board fully shifts underneath me. There’s one in my normal ride and I can not master it. I just turn extra hard and try to hit it closer to perpendicular.

I think #7 is spot on. I can feel myself getting shaky every spring season when I skate less that winter.

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#More_Tuning

So I did all of these:

And it was a night/day difference.

First off, Huge shout out to @bboybowzer, who mailed me not 2 but 3 sets of basically brand new shock blocks, and is now ignoring my asks for his paypal address (pretty sure) because he continues to be image
(still happy to at least send you beer/coffee/boba money brother, you’re too kind)


  1. De-wedge & wedge the Bro

Decided to go full bore and throw wedges on both sides. CAD’ed up some quick wedges and printed one of each in PETG with a ton of vertical perimeters for good measure.
Files are available here: Printables: Matrix II Truck 5 Degree Wedge

I realized after starting the install, that these outpaced the truck mounting bolts I had. They’re relatively thin - only 2mm at the thinnest point, but 5deg is enough to need +7mm on the thick side.I started shopping around for some M5 x 45 flathead, hex drive, zinc-plated alloy steel bolts… might as well be trying to buy a moon rock. Doesn’t exist unless I want to pay the McMaster gods their voodoo shipping money.

Then I realized that’s almost 2 inches of truck bolt - a little long for comfort. Much better to reduce the rubber spacer on the Matrix IIs and save the money for future esk8 parts. So I CAD’ed up a new half-height spacer and printed two in 100% infill TPU.



(Wedging is confusing, like MBS binding orientation. Bro tips are 30degrees. I want a lower pivot angle on the rear for less leverage / more stability / less turn, and a higher angle on the front for more turn / more agility.)


  1. New Shock Blocks

The old reds I had on there were noticeable shorter & fatter than the new ones. The oranges less so, but still. Replaced all four.



Wild.

I love the bottom graphic of the Haero Bro. We don’t get to see it enough :slight_smile:

New blocks! Still red rear, orange front. Gave them all 1-2mm of preload for good measure, with loctite on the bolts, and took it for a spin. Rides noticeable more stable! Much less tightrope-walking at high 20s and low 30s (mph). Big fan of these changes. And with bindings, I bet if I threw myself over hard enough, I could do a full 180 in one lane of the road. 1.5 lanes is relatively easy.

  1. 150x50 Sunmates

I did not fully comprehend how small the sunmates are next to the 200 Clevers I’ve been rocking for the last year.

Zero clearance lol. I need to remember I can’t drive over everything monster-truck style with these.

Looks ridiculous, but I love the way the tires sit on these Fivestars. I need to build a true street-only carver on small pneumatics asap.

Too bad they’re wobbly as fuck. As in, the whole board starts vibrating once you hit ~25mph. It easy to see just by spinning the front wheels. I’ve gotta add weights or slime or both. Still, the quick test run was super fun. They feel much more planted, more direct - you feel all the cracks in the road, but (maybe my imagination) it feels like there’s less sidewall flex, less gooey disconnect. Even at low(er) speeds, it was really fun to rip around the neighborhood.

I definitely need to build a carver for the gokart track.


In other news, still troubleshooting my lazy DAVEGA problems - Davega problems or questions - #320 by sleepless. VESC connection drop offs under throttle all the time. Super annoying to not really know how fast I’m going.

Also had a balance wire snap on one of my NESE packs and I didn’t notice until I tried to charge. Almost had a heart attack when I plugged the charger in and the LLT BMS cell values were all over the place. Just about tossed the pack out the back door in a fit of adrenaline. Luckily an easy fix, but damn. It’s not real until it gets real.

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Slime and weights help, just not for egg-shaped tires…
My solution lately - buy 6 and hope you get 4 good ones :grin:

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It’s crazy how those shock blocks shrunk like that! I was expecting them to spring back.

How are you finding the MakerX GO-FOC DV6?

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