Single-speed track stealth ultralight

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Chalo
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Re: Single-speed track stealth ultralight

Post by Chalo » Jan 05, 2018 4:09 pm

You can do that, sure. But you are limited to rims that don't have alternating tilt or stagger in their holes, which is not very many of them. And when truing, you have in effect half as many places to pull on the rim-- the same basic problem as paired-spoke wheels.

You would run into the problem that paired-spoke wheels were designed to circumvent, which is the rim zigzagging from side to side when the opposing spokes are too far apart from each other.
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Re: Single-speed track stealth ultralight

Post by Buk___ » Jan 05, 2018 4:40 pm

Chalo wrote:
Jan 05, 2018 4:09 pm
You can do that, sure. But you are limited to rims that don't have alternating tilt or stagger in their holes, which is not very many of them. And when truing, you have in effect half as many places to pull on the rim-- the same basic problem as paired-spoke wheels.

You would run into the problem that paired-spoke wheels were designed to circumvent, which is the rim zigzagging from side to side when the opposing spokes are too far apart from each other.
I also tried a 2 cross pattern, but it probably suffers the same flaws:
36AlignedFlangeHoles2Cross.jpg
36AlignedFlangeHoles2Cross.jpg (88.23 KiB) Viewed 315 times
Last edited by Buk___ on Jan 05, 2018 6:11 pm, edited 1 time in total.

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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 05, 2018 5:57 pm

Thanks for the input. You guys had pretty much the same ideas I did today... I guess my options are:
  1. get 9 longer spokes and 9 shorter spokes with a length difference +/- the length of what the offset should be
  2. try to do a 1 cross or pseudo-radial lacing that may not be strong enough for Atlanta potholes
  3. try and get BMS Battery to send me a new motor or outer shell for my existing motor
  4. take the hit and get a different motor from another source
This friggin' sucks. I really don't want to have to have 3 different length spokes on my wheel so I can do a 2 cross. And I really don't think a radial lacing pattern would be strong enough to use for a daily commuter in Atlanta Ga. We have seriously shitty roads here. It's more like paved potholes rather than streets with some potholes in them.

I've emailed BMS Battery hoping that I hear back from them and they'll provide warranty service for this manufacturing defect.

Just so I can plan for the worst case scenario, what would a comparably small hub motor be? Are there any Bafang hubs that are around that 100-110mm size that are available from a US source?
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Re: Single-speed track stealth ultralight

Post by Chalo » Jan 06, 2018 4:47 am

Radially laced wheels are every bit as strong as cross-laced wheels, except in torsion. Your hub shell doesn't even allow true radial lacing, so the amount of torque that the small motor can put out shouldn't be a problem.
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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 09, 2018 6:31 pm

Good news!

BMSbattery is going to send me a new Q100H shell along with tools and instructions to change-out the defective hub shell for a good one.

I'm actually looking forward to having specialized tools for taking the hub apart; they may prove to be handy to have in the future. I know some people have made rigs to take these apart, so I'll post pics of what they send when they arrive for comparison.
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Re: Single-speed track stealth ultralight

Post by Chalo » Jan 12, 2018 2:13 am

That is good news indeed. Let us know when it all comes together.
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Re: Single-speed track stealth ultralight

Post by amberwolf » Jan 12, 2018 3:27 am

BTW, there is one other option you didn't list: --redrilling one flange of the hub with the correct hole placement, in-between the existing holes. ;)

It'd be a bit weaker flange than usual, but I suspect it's strong enough to work fine like that.


(I redrilled my MXUS's flange for smaller holes than what it came with, so I could use regular bicycle spokes on it without washers or other bandaids to keep the heads from just coming right thru the giant holes it came with--no issues with the flange yet, despite the loads and potholes)
https://endless-sphere.com/forums/viewt ... =2&t=86180
https://endless-sphere.com/forums/viewt ... A#p1261116

Hopefully the new parts and tools they're sending you will fix the issue, but if not, you do have the above as an option. :)

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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 14, 2018 6:44 pm

Huh, that's a good suggestion too. I hadn't thought of trying to drill a new set of holes in the flange. It's good to hear that that technique worked for you. Hopefully it won't be necessary, but I'll keep it in mind.

While I wait for the new hub shell and tools, I got some other goodies for the build. My Phaserunner and the last bits I need to build the battery pack arrived, so I'll have some stuff to keep me busy while I wait to finish the wheel.
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Re: Single-speed track stealth ultralight

Post by Papa » Jan 14, 2018 8:48 pm

zro-1 wrote:
Oct 30, 2017 6:35 pm
This may be useful to the rest of the forum: I was able to decipher the info printed on the motor casing. Here's what the motor reads:

AKM17062901002
AAD3620A
H


AKM = the manufacturer, Akiema (or however that's spelled)
170629 = the date of manufacture (2017-06-29)
01002 = The motor model and version (0100 = Q100, 2 = version 2)

AAD = I haven't been able to figure that out yet, but I believe it is the code for the style of gears/brakes the motor can use (freewheel + disk/rim brake)
36 = 36 volts (yeah, I'll follow that :D :wink: )
20A = 20 amps
H = the H-series of the Q100
I have two, recently purchased (12/2017) Q100H 328 - Both front hubs.
Gears - motor 15t / first stage planets 36t / second stage planets 23t / final ring 78t

Ratio = 8.139

AKM17092301002
AAD3616A-H
QC-PASS round sticker stating "16 Inches" (white/green)

AKM17092301017
AAD3616A-H
QC-PASS round sticker stating "16 Inches" (white/green)
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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 15, 2018 8:08 pm

That's great info Papa! Thank you for sharing it on this thread.

I got my pack welded and the BMS and solid state switched hot-glued in place. I'll post some pics of that in a few minutes.
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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 15, 2018 8:18 pm

OK, so here's the pics of the pack in progress...

First I used the very nice welder by Aulakiria to weld the parallel connections
IMG_0121.jpg
IMG_0121.jpg (100.61 KiB) Viewed 146 times
Then I knocked out the series connections
IMG_0123.jpg
IMG_0123.jpg (78.35 KiB) Viewed 146 times
I tested the voltage after the welding was done and the pack read at a nice steady 49.95V. I did test each cell ahead of time to make sure they were all ok, and every cell read ~3.64V (back when I first got the cells from Vruzend).

Next was placing the BMS and the on/off solid sate switch. I got the BMS from Vruzend as well, and I got the solid state switch from Luna Cycle.
IMG_0125.jpg
IMG_0125.jpg (104.61 KiB) Viewed 146 times
I still need to solder all the wires to the battery, but I'm going to wait till tomorrow after work to do that.
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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 16, 2018 8:58 pm

I got the BMS and on/off switch all wired in tonight. I verified the on/off switch is working correctly and I'm testing the BMS by hooking it up to the charger now.
IMG_0129.jpg
IMG_0129.jpg (102.83 KiB) Viewed 120 times
Wires all soldered on
IMG_0130.jpg
IMG_0130.jpg (83.62 KiB) Viewed 120 times
Closeup of the balance wires and primary discharge wires
IMG_0131.jpg
IMG_0131.jpg (118.38 KiB) Viewed 120 times
Charger port and on/off button
IMG_0132.jpg
IMG_0132.jpg (81.17 KiB) Viewed 120 times
Same, showing the button illuminated when the power is on.
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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 21, 2018 11:02 pm

Well. I got my battery shrink-wrapped and into the seat bag, and I hated it. It made the bike feel really top-heavy and running wires cleanly was going to be a pain in the ass. So... I decided I'd deconstruct it and make a backpack battery.

I recently got a really nice waterproof backpack from Timbuk2 that will perfectly fit a 13s2p battery down in the bottom of it. So that's what I'm going to do.

Here's the plan:
newBatteryLayout.jpg
newBatteryLayout.jpg (97.85 KiB) Viewed 41 times
I'll post pics of it when it's done.
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Re: Single-speed track stealth ultralight

Post by Buk___ » Jan 21, 2018 11:38 pm

zro-1 wrote:
Jan 21, 2018 11:02 pm
Well. I got my battery shrink-wrapped and into the seat bag, and I hated it. It made the bike feel really top-heavy and running wires cleanly was going to be a pain in the ass. So... I decided I'd deconstruct it and make a backpack battery.
Isn't moving the batteries even higher (onto your back) going to make the entire system -- you and the bike -- even more top heavy?

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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 21, 2018 11:45 pm

Yes. But the weight is on me, rather than being on the bike. With the battery pack in the seat bag it felt like the bike wanted to tip over more than I intended it to. If the weight is on me I figure my body will compensate better.

I know before I was saying that I already had a bunch of weight on my back and didn't want more, but after feeling the weight at the top of the bike (basically between my legs) I wasn't happy with it.

If I wasn't going for a stealthy build, I'd just toss the battery down in the triangle and be done with it, but I don't want a big battery in there.

My game plan now is to attach a magnetic connector to the bottom of the seat and have the battery in my backpack.
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Re: Single-speed track stealth ultralight

Post by Buk___ » Jan 22, 2018 12:18 am

zro-1 wrote:
Jan 21, 2018 11:45 pm
Yes. But the weight is on me, rather than being on the bike. With the battery pack in the seat bag it felt like the bike wanted to tip over more than I intended it to. If the weight is on me I figure my body will compensate better.

I know before I was saying that I already had a bunch of weight on my back and didn't want more, but after feeling the weight at the top of the bike (basically between my legs) I wasn't happy with it.

If I wasn't going for a stealthy build, I'd just toss the battery down in the triangle and be done with it, but I don't want a big battery in there.

My game plan now is to attach a magnetic connector to the bottom of the seat and have the battery in my backpack.
Struck me that you might fit your 26 batteries like this:
junk.jpg
junk.jpg (51 KiB) Viewed 34 times
. And if they were housed in some sort of semi-rigid container of the right color, it would almost disappear.

Then I guess it'd be whether you could live with a Q factor to clear an extra 20mm each side of the downtube.

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Re: Single-speed track stealth ultralight

Post by zro-1 » Jan 22, 2018 12:41 am

I actually had considered that but gave it up pretty quickly.
  1. Its even more bulky/wider than a downtube battery
  2. It'll still look like I have shit strapped to my bike
  3. I'm tired of wide Q factors
  4. I wear a backpack anyway commuting and shopping
  5. I finally have a comfortable waterproof backpack that I don't feel puts a battery at risk
  6. There's now a magnetic connector in case I fall off the bike
Most of my previous concerns were with having something that could go into thermal runaway and burst into flames on my back, but with a BMS, magnetic connector, and a padded, waterproof bag, I think it should be ok. And nothing is more stealthy than a battery in a backpack. The only things on my bike will be the controller and motor.
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