It is beautiful Brandon! 
Will you be making me a set for Christmas? Lol…
Looks great though! But seriously, how much? I wish i could make them.
The front pivots have relatively low loads on them due to their proximity to the contact patch, they basically only experience vertical shear. The rear pivots have significant bending loads on them and will probably break first, despite being chunkier.
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Lol exactly. Putting a steerer tube on these things might work a little better but it looks so awkward
I built this last year to see if i could ride it… love this thing but it definitely needs that style steering geometry or a different rake maybe. It does great offroad, on pavement it gets speed wobbles when you pass18mph. Better with higher front tire pressure but then wont turn much. This is my second spring setup.
BM-1109 48V motor
Flipsky 75100
VX2 remote
13S 4P 60A 19.2AH
Ive done 26mph on it on the road
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It really does look awkward lol
As for recommendations, i believe your 12s 4p is right on target. You could have 864Wh/20AH & 100A/4320W continuous nominal using Samsung 50S 21700 cells.
Kudos for getting it working, but yeah it looks like it has very little trail. Steerer tube vs 4 bar links shouldn’t make too much difference at speed I think. I wonder if having too much spring force plays into it as well, but that’s kust speculation
I wasn’t really happy with the look of the bottom cover plate on the board. I decided to give it a little character. Below are the original design, and the new design to compare.
I had always planned on pressing this plate out of aluminum so the changes really didn’t ad a lot of work to the part. The tooling was still the same size and the machine time didn’t change much. Since the design was finalized, it was time to go to work on the tooling. Here are a few pictures.
Now, with the tooling out of the way, it was time to press out the bottom plate. I pressed it out of 2024-O aluminum. I will be heat treating it to 2024-T for added strength. Since I haven’t heat treated it yet it hasn’t been trimmed to size. Anyway, here are a few pictures of it in its current state.
I like the honeycomb look of the part. I’m contemplating calling the board a “Buzz Board”. What do you guys think? Anyway, thats all for now.
Brandon
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That shape should help a lot with rigidity of the plate, what did you use to press it?
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I used a 120 ton rubber press. I pressed it in rubber using the female tool first, then pressed it between the male and female tool. I could have easily done it with a shop press, but thats not as fun.
Brandon
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Amazing craftsmanship Brandon! This is a very cool project and very well executed. Looking forward to reading about your thoughts when you finally get to ride it.
I will say that 63100 motors are usually not a great motor. Outrunners should be kept closer to a 1:1 aspect ratio if possible otherwise the rotor often develops vibration. For 63mm motors without a support bearing I wouldn’t go above 85mm length. My go to combo for best performance and reliability these days is the Radium/Reacher 6485 and Makerx DV6 pro vesc (being the designer of said motor I’m biased but most people seem to agree lately). If you can get good gear reduction on 205kv I’d go with that, unless you live somewhere with a colder climate and can gear down 245kv which will give you the most power at 12S.
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Have you tried the Bioboards 65100 at all? Seems like Heath has been running them for a while now w/o any major issues.
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Have not tried them but would be very interested to compare the thermal performance. They should have more grunt than the 6485 but lower efficiency and more drag. We dont really test other motors at this stage, I just focus on making the 6485 better
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I’ve heard that they are less efficient because they cannot dissipate heat easily (b/c of battle hardening).
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And drag from the big grease filled bearing
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I might try that setup. Although id go with the Makerx SV6 since im single motor. It looks like the Reacher 6485 isn’t available until February? Am I reading that wrong? Is there a way to get it faster?
Thanks for the compliment on the build. In all honesty I’m just fortunate to have access to the right equipment. Maybe if i get this thing sorted out I’ll build a couple kits and more people have a go at building one.
Brandon
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So it looks like the SV6 has the lower power configuration from the standard DV6. The reason I always recommend the pro is that aside from lower resistance fets that run way cooler, the shunts that measure motor current have been also upgraded to measure twice the current, which means the DV6 pro can measure bigger current spikes without triggering an ABS overcurrent fault, and therefore actually utilise the capacity of the 6485 motors.
I have used the makerx Hi100 with good power levels so maybe give that one a go as its a single vesc.
February is a conservative estimate for when the motors will ship. Should be closer to mid Jan
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The g300 could be a great option
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This is really cool dude! Nice machine work. 
I especially appreciate the mold/die work.
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