30 psi. 7” novas
For science I’d be curious to see how the mileage compares at 35psi
For the time being I will increase tire psi to 35 and lower phase current to 90a each side. Longer term thinking lower kv motors.
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If you have any 8in tires I’d recommend putting those on and do the same ride. Other than that I don’t rl see any issue with 16s 173kv.
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Swap to a higher teeth count pinion, you will have more copper losses, but less iron losses. With reachers especially high voltage high kv, a lot of heat is iron losses (coming from rpm). They are inefficient at high rpms but they are good at cooling (allowing more power) and staying reliable despite being hot.
Cruising around doing long range rides it’s really the iron losses you need to minimize and not copper losses. Gearing for a higher top speed (either by larger tires or bigger pinion) will increase range. Lower kv is also a good choice though I’d only swap motors to change kv if I had another board waiting for motors at the kv you already have now.
Just a quick note on wheel diameter, most people think it affects range negatively but it doesnt. Tire deformation affects range. I have about 50% more range cruising on a 9” tire with stiff sidewalls and square profile than the old scooter style 8” tires with soft sidewalls and round profile.
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When I went from well worn Chen Shin 8x3” turf tires on my front truck to 2.80-2.50-4( 9”) Kenda K473, I expected to lose some range.
The Kendas were more comfortable at twice the PSI, and my range increased instead, though I have no hard numbers.
I am only running them at ~23PSI.
The Kendas are a bit lighter than the worn turf tires.
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I really appreciate this response. I’ve been talking with folks this morning trying to understand erpm and what could be leading to losses.
These motors not cheap so definitely trying to avoid that if at all possible.
Actionable steps:
Lower phase amps to 100a
Increase psi to 35
Larger pinions thinking 22t 
When these tires cord potentially go 8”
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Might take a while. 
I wouldn’t lower phase amps much with efficiency in mind, unless you are chasing record efficiencies. It’s not gonna increase efficiency much (unless you full throttle everywhere now), as most of the losses accumulated over a long cruise come from rpm and not current.
Higher pressure definitely helps as well, though that comes with less comfort, and at some point your feet will also become a bottleneck
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Yeah, ok. I do like the power I’m seeing now at 125a. Definitely “slow” in terms of racing stuff. But enough to have fun in the streets. Will do some experimenting. Sucks to build a big range board then get worse than expected efficiency!
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67t SPUR GEAR FAILURE. Been noticing slight oscillation from it last few days. Marked it up to plastic hubba-hub must be warping over time. Little did I know it was the gear separating from the core. Last night took spur assembly apart from rim and reinstalled to try and true everything and it didn’t help still swaying back and fourth like a poorly trued bike wheel. After tinkering with it for awhile I was really at a loss for why it wasn’t true. Reinstalled best I could and greased. 1 mile into my morning skate commute to work the spur separated from the core! The oscillation I was noticing was in fact the gear already slightly separating from the core.
It was quite a scary situation because it happened about 31 mph and gear popped and was grinding. I had to focus on riding it out, couldn’t look down at the problem, and when I tried using brakes it sounded like spur was loose, didn’t want it to catch and send me flying. What resulted was me letting off all throttle or brake input and just coasting to a stop over maybe 800 feet or so. So thankfully it didn’t seize up and send me flying.
NOT casting blame or claiming manufacture malfunction, it’s been rock solid under various scenarios and what I’d consider heavy forces. If I had to explain what happened, I bet when I had the pinion malfunction earlier this week it caused weird forces or vibrations that must have broken the bond between core and spur gear.
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Not the first time I see something like this happen, though thankfully it’s quite rare. But I think the gear should be made one piece, or use fasteners to keep it one piece not just press fit.
I don’t believe that the pinion failure had anything to do with it.
If you want to give it a try I can send you some laser cutting files that you can order from sendcutsend. At least that’s one piece. Not as well hardened as proper spurs but I have 40-50 racing sessions on my set and they still look reasonable. I do oil every time though. Used to use spray on white lithium grease but moved to just a drop of 5w30 engine oil because it stays better and is less messy. It doesn’t have any sudden failure mode. I ordered 8x 78T when I bought mine and it was around 30$+ tax each from 1/4” 4130 steel.
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That’s a really good price and good to know they can be reliable from sendcutsend. I’ve been designing my own spur for a little bit and most likely going to have it made at Konlida since I’m trying to have spurs that last longer. I’ve been told I can get 42crmo quenching and blackening done there.
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If it helps I get quite similar mpg to that on 16S, 170kv 63100s, 16:80 gearing, and 7” old SKP or 8” square slicks.
I don’t have much good info due to no long rides that fast and sometimes a couple hundred metre elevation change.
Maybe lift it up and throttle it to your average speed then read vesc tool to see how much efficiency there is to be gained.
You could definitely reduce freespinning losses by gearing higher or using larger tires but that would decrease your max accelerating force. Another option is using only one motor. I tried and efficiency improved but grip is hilariously bad and it’s only easy if you use belts.
Definitely helps! I’m fairly new to vesc world so not sure what’s normal for given riding styles. So far, greasing gears and increasing psi seems to be helping efficiency. I tried lowering motor amps to 100a per side, but then I was full throttling from every stop. 125a to me seems balanced between slow and raceboard fast, while still trying to respect the d100’s limits.
I will be putting on Radium 125mm soon, I’m so curious how much it will boost efficiency and range.
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Interested to hear how the radium 125s will go regarding efficiency. I’ve got a build coming up with them also when some parts free up from the raceboard eventually
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I posted in the skatepacking thread about this trip, but this is becoming a nice place to look back on progress, so I’ll post here also.
There’s this term called micro adventures where you don’t have to travel cross country or to exotic places to experience adventure, sometimes adventure is closer than we realize. Skatepacking for me, is the coolest way to explore places closer to home in a more intimate way. Coming from a hiking and camping background skate-packing is so bad ass, I get to skate and camp in rad places.
I chose to skate up the coast again. 15 miles further than I have previously. I need to figure out a filming situation as I feel like I’m doing some crazy shit sometimes. Since I started esk8 I’ve always wanted to ride as fast as cars or at least be able to co-exist and keep up with the flow of traffic. I’m pretty much there up to 45mph, road conditions dependent, a really crazy achievement. This trip there were some 35mph speed limit stretches through town I was able to accelerate faster than the cars from stop light and stay ahead of them for blocks at a time.
This trip was no nonsense just putting down miles. I’ve never ridden this fast for so long, 45 miles first stretch I think I took a 15 minute coffee break! Trip clocked in at 147 miles total.
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WTF who made the choice to press fit this? Heat them to go around the aluminum when manufacturing? I wonder what happens then when the gear teeth heat up from being used🤦
This is so cool.
The distance is wild.
But to me the speed is also so wild
I think my limit is holding 30 on my Flux with Dualitys. It’s wild that you you are holding at 15 miles faster…
Do you rock all the gear? Have you had any scares at speed?
Yes! GEAR.
Gloves, armored jacket, full face, hip and but pads, leatt knee/ shins.
I’m not god of course, I know something bad can happen anytime. I see people being killed all the time from being struck by vehicles. I try to be very aware of surroundings, head on a swivel, aware of blind spots, aware of cars pulling out from driveways.
I had one scare training high speed on my stooge last year a car pulled out in front of me. I must have been going 40, dodged the car pulling out, had to swerve into the oncoming lane of traffic and fortunately there was a large enough gap in oncoming cars I was able to make it across the road to collect myself. All happened so quickly.
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