Project IRK Scooter.
28My last IRK was huge, and there was an electric scooter at the bottom of the box! Non-functional, of course, this is Meh after all.
I figured I’d put the details of the revival project here.
I know IRKs are supposed to be random, but this one feels like someone at Meh knows me. I’m both a motorcycle nut and an electronics geek, so a broken electric scooter is a perfect winter project for a guy like me.
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The scooter was crashed - there’s cracked and scuffed plastic in several places, but nothing disabling. The battery is completely dead, and there’s no charger.
@blaineg If it’s just a matter of charging it up this will be a very short thread. I hope there’s at least duct tape involved.
@sammydog01 Have no fear! No duct tape yet, but giant heatshrink is involved.
I found several good pointers on the
on the net. Meh sold them a couple of years ago for $400. Maybe this was a warehouse bike? Crashed in the warehouse? If so, let’s hear the tale, if it won’t get anyone fired.
@blaineg By the way, that’s a link to the sale page. 78 sold, did any of you buy one?
Anyhow, one site led to a battery charger on Amazon for a mere three times the price of the scooter. I’m such a spendthrift! Got next day delivery for free too, so I was working on the scooter the day after I got it.
Alas, the battery charger did nothing at all.
So I pulled the battery pack, it’s in the diagonal frame tube.
It looks like some damage on one corner, but it’s completely superficial.
The next step was skinning the battery pack. The outer layer is blue heatshrink tubing, then there’s a layer of sticky plastic sheet. Here it is stripped naked.
The circuit board is fine, and the single fuse is intact.
The battery is an array of 40 Samsung Li-Ion cells, arranged as 10 sets of 4 cells.
Each set of cells is completely dead. Nominal voltage is 3.6 volts, and they varies between 0.0 and 0.3 volts. Not good.
@blaineg These pics make me sweat a bit. I have an idea of the angry pixies within, both the electrical type and the burny type.
@fibrs86 Yea, there is a lot of potential for excitement with Li-Ion cells, but these Samsungs have protection circuits on every individual cell. And from what the datasheet says about testing for failure, they are pretty robust.
After doing a bit of study, I found that the Samsung cells have a shutdown mode if the voltage drops below 2.5/3V.
A bit more looking found a safe way to charge them by hand. (Dave Jones’ EEVBlog is a wonderful thing!)
So I charged each set of cells at 1 amp, until they reached 3 volts. Each set of cells was holding some voltage (around 2-2.5V), so I hooked the battery pack back up to the scooter and plugged in the charger.
After thinking about it for a minute or two, it started charging! After an hour or two, the whole pack was reading 36 volts, which is what we want.
I didn’t let it charge overnight as I don’t trust it yet. But I hooked it up again this afternoon, and it finished charging after an hour or two.
Full charge registered 41-42 volts, which is spot on.
Putting the battery pack back together.
Sticky plastic sheet all in place. And the biggest shrinkwrap tube I’ve ever used.
Getting there.
More shrink tube.
Starfleet authorized heatshrink gun.
@blaineg That’s cool!
@blaineg Hey, where’d you buy the big shrink tube? I have some work I’m doing on a similar battery pack and that stuff is hard to find.
@The_Tim Amazon, of course!
I just searched for battery pack heatshrink. Typically it’s 3 feet long, in varying widths. Most of the sellers measure the width of the flattened tube, so double that to get the circumference.
@The_Tim This is the one I bought: https://www.amazon.com/gp/product/B07W4HK76V/
They call it 180mm, but that means flattened width, so 360mm circumference, and 115mm diameter.
My pack is about 55 x 70 mm, so circumference is 250mm. Heatshrink typically shrinks 2:1, so 360mm shrinking as small as 180mm handles my 250mm about right.
Oh, it’s 3 METERS long, not feet. I’ve got a lot more than I thought I did!
But it was only $12.
@Fuzzalini The phaser is The Wand Company replica. They scanned an original prop and did a great job of replicating it. I got it about half price on a closeout sale.
@blaineg I realized later what a nerd I must be to think it’s cool. It’s totally f’ing cool and I’m going to buy one for a friend.
@blaineg
Why did I read that description and company name as “EndYourLife”? Had to do a double take.
That’s probably me being a pessimist.
@Fuzzalini If you like the Phaser, keep an eye out for the Communicator. Though the prices on both have gone insane now that they’re out of production. I got lucky when BestBuy closed them out a couple of years ago.
The Phaser is also a TV remote, and the Communicator is a Bluetooth phone gadget.
https://www.thewandcompany.com/phaser/
https://www.thewandcompany.com/communicator/
@Fuzzalini They’re working on a Tricorder replica.
https://www.thewandcompany.com/tricorder/
Sweet project!! We have the same bench supply and anti-tamper bit set.
Love the starfleet heat gun. But yeah, that shrink tube is bigger than anything I’ve ever used.
@mehcuda67 The roll of far more than I’ll ever need was $12 from Amazon. Also with next day delivery - I’m getting used to that.
Can’t wait to see if it works! I have a Dynamo scooter from Hover-1, it’s a very nice solid electric scooter.
@PooltoyWolf Solid is a good word, this thing is about 50 pounds, you wouldn’t want to push it far.
The folding is a neat trick, but I wonder a bit about the single locking pin that everything relies on…
@blaineg Mine folds too, though just like a standard kick scooter. Seems fairly sturdy.
@PooltoyWolf The lock mechanism seems pretty substantial. Just one of those weird thoughts that drifts through your mind: “What if it did let go…?”
@blaineg I’d probably die. Well, get a leak or a puncture, at least!
This is aMEHzing! This is maybe the first time I’m both envious and happy for someone else’s IRK. They certainly sent it to the right person! Thanks for sharing!
Interesting thread. Thanks for sharing.
That is really cool! They certainly sent it to the right person.
So where were we? Oh yes, the battery works, and is hooked up again. The scooter powers up.
And I thought I fixed the loose/binding throttle problem. There’s a setscrew to secure it to the handlebar. And once it was secure, the sticking/binding went away as well.
The only problem is I’ve got no drive from the rear wheel.
Wednesday I was getting rotation, so I know the motor works, but I couldn’t stop it with the throttle. Now there’s not even a twitch.
Is this progress?
So I pulled the throttle and tore into it.
Here’s the ignition cover, throttle assembly, and wiring harness. The white connector is for the throttle.
This is the front suspension (look at that cute little pair of shocks!) and the brainbox.
And the throttle.
I was expecting it to be a pot (potentiometer, or variable resistor, like most volume knobs, etc.), but it’s a Hall Effect sensor. The little arc in the middle is the magnet, and it presses into the slot you see at the top of the twist grip.
I know the principle of the Hall Effect, but I’ve never worked with them. So I did a little more studying, and I know how to test it now.
Since the throttle assembly was pulled out of place, I’d wondered if there was damaged/intermittent wire, but it all tests solid.
It kind of went SPROING! when I opened it up, so I hope I can get it all back together.
@blaineg hall effect seems like an odd choice. The ones I worked with output pulses and something had to measure the time between them. Great for rotational speed but not position unless you tracked pulses the entire time.
Probably the price has come down and they might be combined with a chip to translate to position.
@fibrs86 It’s got a 5V supply, and the DC output varies from 0.9 - 4.3V for zero to full throttle.
The spedo reported 20mph at full throttle, on the kickstand.
@blaineg @fibrs86 HE is very common in accelerator pedal sensors for their reliability. there’s often an ASIC built into the sensor to produce ratiometric output – analog voltage or PWM. (Accelerator pedals usually have 2 for redundancy and error detection.) Even the rocker switches on our truck dashboard have (digital) HE sensors.
@blaineg @walarney I’m amazed at the parts available for $400 scooters and 3d printers that were not available for $1M construction equipment 15ish years ago. The HE and microcontroller technologies have been around for a while, but once they hit some manufacturing threshold the price drops out and suddenly they are on everything (though I bet many of the construction models I worked still haven’t changed).
Oops, I got a test clip caught in the connector.
@blaineg It took way too long to get that extracted, and I wound up mangling it some.
@blaineg Was it still useable?
@AuntMean67 Yes, I think so. The probe clip was more mangled than the connector contact, but I was able to straighten it out.
This was one of those “I probably shouldn’t…” moments. I’d thought of finding or making some sort of blade to slide into the connector, and hooking the probe to that. Then I looked at the flat hook on the probe and thought it would work, and it did - until this one went under the bend in the contact and got trapped.
It took over an hour to get it free.
The connector is clamped in the soft vise jaws, in front of the phaser. Various weapons of attack are scattered around.
@blaineg You have me obsessively clicking refresh, hoping for the next riveting update!!
@shahnm Thanks! I’ll try not to disappoint.
Today’s goal is to get the throttle working, one way or another.
This project is truly Meh, and probably more of a slow burn regret kit.
Yesterday was mostly screwing around with that connector, and figuring out Hall Effect sensors. Just in case the sensor is the problem, I grabbed a cheap throttle assembly off of Amazon, again with overnight delivery. Now I’ve got a backup if I need it.
How ugly are these grips? And who in their right mind would use aluminum for grip material??
But it was $12 with free next day delivery, and that’s what matters.
The $70 Banggood digital microscope was a great help in identifying the throttle sensor.
What are the chances they would send this to someone who would take the time and has the know how?
Amazing.
@RiotDemon I’d guess on occasion they do choose whom to send these one of a kind things to. I was called, years ago, about the pallet of broken TV’s. JonT called me. I had posted I had taken 2 broken laptops and made one working one out of them and he said that was why I had been chosen for the TV’s. I had to say no as I literally had no place to put a pallet of anything. Too bad too as the person who got them got several of them to work. It was sad I had no place to put that as all I had at the time was a 1993 one that was 12" with a converter box (that only croaked a couple of years ago). I noticed someone who had complained their laptop broke got a working one. I’d imagine this doesn’t happen often but why not? If a person they have in mind gets an irk, then meh knows the item is unlikely to be thrown out and instead it will be fixed and used and or is really needed and will be appreciated even more.
@Kidsandliz @RiotDemon If you Meh.com folks have any other cool projects for me, feel free!
POWER!!!
But I’ve still got to reassemble the throttle. Wish me luck with the return spring.
@blaineg
I don’t know what was wrong with the throttle, but I “fixed” it. I took it apart, tested it, put it back together, and it works perfectly. Installing the spring turned out to be a lot easier than I expected. It’s almost like they designed it to be worked on.
“I’d rather be lucky than good”?
First flight, wearing a helmet as requested.
Working on getting a video up.
Land speed record attempt #1.
@blaineg Yes, it ran out of power trying to cross the lawn!
@blaineg Excellent progress! Though I couldn’t help being distracted by the view…and your bird feeder.
@blaineg Go! Go! Go! This is really exciting knowing the work that went into it.
@blaineg Was the battery fully charged?
@ybmuG We’ve got the Wasatch Range of the Rocky Mountains just to the east of us, the Great Salt Lake to the west.
We had a great sunset tonight that didn’t make into the frame of the video.
@fibrs86 Yep, full charge on the battery. It’s still showing full after that extensive test ride.
The acceleration is leisurely, at best. The power is, well you saw it.
@blaineg @fibrs86
More Power!
@blaineg That’s spectacular! Always love visiting the Rockies. Not so much lately, sadly…
@blaineg @ybmuG Yes the bird feeder looks like a really nice one. You get a lot of birds use it?
@blaineg Well that is a nice reward for your work - that it works!
@ybmuG Oh, we’ve had a hawk raid the bird feeder a couple of times in the last month. He’s been unsuccessful, but it was exciting for everyone involved!
Here he is on the neighbor’s fence, as I pulled into the driveway.
@Kidsandliz @ybmuG Yep, a lot of birds, mostly sparrows & such, but there’s a family of quail that’s been around since we moved in, and a dove that visits occasionally. The quail will rarely try the feeder itself, but they’re very happy with what everyone else spills on the ground.
Once there was a stunning red & yellow bird, about the size of a jay, that I’ve never seen since, or been able to identify. Robins visit a lot when it’s warmer.
We started with the small feeder hanging from the eaves, but we were getting way too much bird poop in the porch. So I bought the shepherd hook to move them out on the lawn.
The larger feeder was from Costco. When it’s completely full, the solid steel hook bends quite a bit, so I only fill 2 of the 3 compartments (the ones facing the house). And I added a hook for the smaller feeder to balance things out.
@blaineg @ybmuG COOL! A hawk!!!
That was actually the second ride. I made a couple of passes between the kitchen and living room, but we didn’t take any video.
How awesome. Your troubleshooting skills are great. It’s really hard to find people with the know-how and creativity to do this kind of thing anymore.
MEALS! DEALS! EELS! AWESOME!
Thank you for sharing every step, it was fascinating! What will you do with the scooter now?
@callow Part of me wants to take it to work, and tear around inside the building (well, sedately tear around). It’s 1/4 mile from my office to the boss’s, and the place is bigger still.
@callow I’ll probably just fool around on it occasionally, and let the nieces & nephews (and their parents) have fun with it, once the plague is under control.
I think your Imgur title is a bit misleading, you’ve got more than $5 in it. This is pretty cool troubleshooting work.
@Oldelvis It’s a title, not a bill of goods!
Mundanes understand “$5 scooter”. Saying “IRK scooter” or “Meh scooter” just confuses them.
If you want an accounting, it’s something like this.
IRK $5
minus roomba clone, foosball table, backpack, briefcase: say a buck each.
That gives a Scooter cost of $1.
(If I deduct the spiffy green IRK bag, then the scooter was free.)
Charger $16.
Heatshrink $12 (with about 2.5 meters left, can I deduct that? If so, $2).
Throttle assembly $13 (unused, I’ll try to return it).
For a grand total of 1 + 16 + 2 = $19 Scooter.
I dunno, I’m an electronics geek, not an accounting geek. I didn’t even attempt to factor in VMP costs.
Oh, how do I figure in the Krugerrands?
Here’s a weird one. Amazon has accepted the throttle return, and it’s free if I take the “Don’t pack it, box it, or label it, just hand it to the UPS store” option. Or if I drop it off at Kohls (I have no reason to ever go to Kohls).
But the usual “print a UPS label, box it yourself, and deliver to a UPS pickup point” option is $6.
So if I do more work, it costs me more money?
@blaineg i know - feels like there’s a catch in there somewhere. We’ve done the Kohl’s thing a few times. It’s the only time we ever go there. And if you’re inclined to buy something while there, they give you a coupon on the spot you can use. That may me the catch - they try to suck you in to buy something from Kohl’s.
@ybmuG The UPS store is only a block away, so that’s no big deal. But the UPS pickup is actually easier for me, since that’s the shipping department just down the hall at work.
@blaineg Ha! The downside of self-employment (and pandemic-induced WFM, for that matter) - no shipping (or IT, or maintenance, or custodial, or any other) department.
@ybmuG The Kohls catch seems fairly obvious, but I’m not sure what sort of impulse purchase I’m expected to make at the UPS store.
I’m not done yet, there’s some bodywork to do.
I’m not sure how they managed this, but the mounting bosses on the right side of the dashboard/handlebar cover and the left side of the under seat/taillight cover are broken.
It must have been an interesting crash. At least I hope so, it would be boring if it just fell off the warehouse shelves.
I haven’t pulled the seat taillight cover yet, but based on what I’ve seen with the handlebar cover, I’ll probably build it up with JB Weld, and then redrill the mounting holes.
@blaineg Seems like someone should fess up and tell the story…
Lunchtime update: I put it in the trunk last night (tossed would not be an accurate description of the Spagthorpe Basselope’s 50 pounds) and took it to work. A couple of cow-orkers had a go at lunch, and pronounced it “Fun”. I set a new personal best of 12mph!
And since some of you have undoubtedly asked: The Spagthorpe Motorcycle Company.
https://cybermotorcycle.com/archives/spagthorpe/
Thank you for sharing all of this. Very thorough, especially the heat shrink and not wrapping in vinyl tape.