What are the sturdiest bike frames that could check into luggage if I build them with a removable battery?

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Issues I'm not looking to address in this topic:
Let's run under the assumption that I can get as many <100Wh batteries by the TSA as I need to, maybe by putting them in power tool battery cases to minimize suspicion. I understand that's not necessarily safe to assume, and I'm going to work around that assumption regardless, so don't clog the thread with that. Let's also pretend I exist in a hypothetical jurisdiction where ebikes up to 5kW are street legal.

The problem:
I'm not much for offroad but it'd be nice to get cheaply around civilized society no matter where I'm at. My ideal bike frame can be either disassembled with a ratchet set or folded until it's packed down to 62 linear inches, but I can't remember the last time my checked luggage was actually measured for that.

I've taken a look at some of the folding bike frames available at local bike shops but if my calculations are correct, when those babies hit 88 miles per hour, I'm gonna' see some serious s...

I don't mind if it's expensive as long as it'll stay with me for a decade or so. I'd need one with a rear rack that I can put panniers on to hide the hubmotor, battery, and controller.

The question:
Is there a bike frame with a rear rack that can fold or disassemble down to (or close enough to) 62 linear inches (rectangular l+w+h) that won't take me to meet Jesus at 45mph? Assume no more than 50mph.
 
The 62 inch thing is a major obstacle. None of the six airlines I’ve taken bikes on were that restrictive.

Still, I trust you’ve done your research and there’s no flexibility on that criteria, so questions are:

1. Why wouldn’t you just put the wheels in one box, and the rest in another?

2. Assuming you managed to compact a suitable bike to 62 inches, is its weight going to exceed the airlines’ maximum weight per luggage piece restrictions?
 
Knowledge is never dumb. Application of knowledge can be stupid.
Mind sharing what you about airline bike packaging.
 
In my experience, bringing a bicycle as airline luggage always requires you to waive the airline's liability for damage. So if you go that way, maybe take on some trip insurance that will cover damages if they occur. If your bike breaks down and fits in a suitcase, you probably won't have to sign away your ability to seek compensation.

I have on my "to do" list a frame whose front and rear triangles pin together with the bottom bracket spindle and the seat binder bolt, so a suitcase that accommodates the front triangle can also fit any other component of the bike. I assume I'll be using 20" wheels and probably putting them in a separate case.

Most airlines stipulate a 50 or 55 lb per piece weight limit before adding a hefty additional fee. Then there's a hard upper limit above which they won't accept the item as luggage (though they might still take it as freight). That makes an e-bike of any kind something that probably must ship in multiple cases. A 45+ mph e-bike is bound to be heftier than makes sense for air travel.

It's probably a better idea to go for a Class 3 type bike that doesn't need to be nearly as heavy to be safe. Moderating the speed gives you more choices of wheel size, and the option of going without suspension, both of which will make the bike lighter and less likely to be damaged in transit.

P.S. -
When my band has traveled by air with equipment that needed portable power, we have used this kind of 100Wh battery that doesn't alarm airport security at all so far:
 
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While it's more money I'd look into a travel frame based bike (with S&S BTC or similar) and a hard case, that way the airline won't really know you're carrying a bicycle. A touring/adventure type of bike with a small geared hub motor would make a great travel setup and could be under 50lbs packed, as long as you can also engineer that multiple sub 100wh battery configuration . A steel frame would make the most sense (easiest to repair) but a Ti frame would be the strongest and lightest setup ... but a lot more money.

 
Note that Grin no longer sells LiGo batteries. So tool packs are the next best thing, easier to get, possibly cheaper, and less puzzling to TSA orcs.
 
Thanks for all the feedback. Some context: My overarching purpose is essentially a longterm cost minimization and privacy strategy. I travel often, and so renting a vehicle not only attaches my SSN or some other financial detail to everywhere I go after I leave the airport but also incurs costs that add up.

1. Why wouldn’t you just put the wheels in one box, and the rest in another?
Limiting myself to a single checked piece of luggage greatly reduces the cost of frequent travel.

2. Assuming you managed to compact a suitable bike to 62 inches, is its weight going to exceed the airlines’ maximum weight per luggage piece restrictions?
Most airlines stipulate a 50 or 55 lb per piece weight limit before adding a hefty additional fee. Then there's a hard upper limit above which they won't accept the item as luggage (though they might still take it as freight). That makes an e-bike of any kind something that probably must ship in multiple cases. A 45+ mph e-bike is bound to be heftier than makes sense for air travel.
The airlines that I typically fly attach a $75 flat rate for any checked "non-motorized bicycle" up to 100 lb and 110 linear inches. As I plan on keeping the controller and battery in the panniers to make it less obvious that the bicycle is motorized when I'm riding it, the goal of <100 lb seems easily achievable even with something like a QS205 in there. Building panniers that convert to a carry-on and personal item is something I can do myself -- I'm no professional tailor but I can sew rectangles. The problem that arises would be checking a bicycle with the rear hub motor on it and somebody rightfully pointing out that it's a motorized bicycle. I could tape packing protection around both sides of each wheel pretty easily and that might be enough to get past a visual inspection, but these are all probably going to go through a scanner. I suspect these guidelines were written with traditional ICEs in mind. Then again, the scanners probably belong to the TSA, not the airline, and these are likely two completely separate steps.

Knowledge is never dumb. Application of knowledge can be stupid.
Mind sharing what you about airline bike packaging.
The knowledge isn't dumb, just me xD
Most airlines apparently have a "fragile and special items" policy to look into regarding checked baggage. It lets people pack sporting equipment like hockey sticks and whatnot, or in this case, bikes.

In my experience, bringing a bicycle as airline luggage always requires you to waive the airline's liability for damage. So if you go that way, maybe take on some trip insurance that will cover damages if they occur. If your bike breaks down and fits in a suitcase, you probably won't have to sign away your ability to seek compensation.
Yeah, but suitcases are limited to 62 linear inches on the airlines I fly, which just isn't gonna' happen. The increase to 110 linear inches, 100lb and the flat rate baggage fee for packages that contain only a bicycle is super appealing to me. If I pack right and cushion the important bits, I'm less concerned about damage than theft. With only the stock bicycle, its hub motor, some low-profile throttle, and an aftermarket rear and headlight, I run pretty short on places to stash an AirTag mainboard in.

It's probably a better idea to go for a Class 3 type bike that doesn't need to be nearly as heavy to be safe. Moderating the speed gives you more choices of wheel size, and the option of going without suspension, both of which will make the bike lighter and less likely to be damaged in transit.
In exchange for better wheel size choices and the option of going without suspension, I lose several destination options. Many of my best friends live in fairly rural areas where there's always a network of ~35mph-ish back roads I can take from point A to point B with the exception of some river or canal where I'll have to merge into automotive traffic for the length of a bridge. I can think of multiple examples of this but don't want to doxx myself. In those situations, I run a lower risk of getting plowed into if I can maintain 45 to 50 mph for ten minutes before ducking back off into the backstreets.

P.S. -
When my band has traveled by air with equipment that needed portable power, we have used this kind of 100Wh battery that doesn't alarm airport security at all so far:

https://www.amazon.com/DEWALT-DCB205-5-0Ah-Lithium-Battery-Pack/dp/B00KWRM5Z4
Well well well, would you look at that :)

While it's more money I'd look into a travel frame based bike (with S&S BTC or similar) and a hard case, that way the airline won't really know you're carrying a bicycle. A touring/adventure type of bike with a small geared hub motor would make a great travel setup and could be under 50lbs packed, as long as you can also engineer that multiple sub 100wh battery configuration . A steel frame would make the most sense (easiest to repair) but a Ti frame would be the strongest and lightest setup ... but a lot more money.
That's pretty neat, but I'm not sure it'll be necessary with a 100lb weight limit.

Note that Grin no longer sells LiGo batteries. So tool packs are the next best thing, easier to get, possibly cheaper, and less puzzling to TSA orcs.
Yeah, I was really hoping the LiGo 10X would come out soon, but it's not looking likely. Very sad.

Thank you all once again for your feedback. Do any of you know of any decent aftermarket headlight or taillight fixtures that I could easily hide an AirTag mainboard in and still be able to get in there to pop the coin battery into and out of?

Can any of you share experiences traveling with an e-bike, no battery? What airline? How'd it go?
 
The Velo Orange Neutrino was developed with travel in mind, and they electrify pretty easily. I've done two Neutrino mid-drive builds (Bafang BBS02 and CYC Photon), with 8-speed Shimano IGH drivetrains. The frames have, I think, Tange IRD-compatible sliding rear dropouts (135mm O.L.D.), which might accommodate a smaller rear hub motor and torque tabs.

30MPH, on a packable bike, would be tops I'd go - averaging 20MPH being more realistic. 45-50MPH speeds are, IMO, not feasible or attainable, given the constraints.
 
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I travel often, and so renting a vehicle not only attaches my SSN or some other financial detail to everywhere I go after I leave the airport but also incurs costs that add up.
Yes agreed but if you are already carrying a mobile phone, there is plenty of personal information you are leaking wherever you go.

+1 on the bike shipping services. I did have a great experience using BikeFlights a few years ago to send my daughter's bike to her when she was at college across the country. IIRC I preprinted a label and brought the boxed-up bike to a local FedEx (or maybe post office?). Got a box from a FLBS that was headed for recycle bin. The most time-consuming part was boxing up the bike, but not too bad. Added bonus: was able to include some care package goodies for her in the panniers.

As a major part of your proposal is to save money over renting a vehicle at your destination, you can calculate and compare the shipping costs to the vehicle renting costs to help you decide.
 
So I finally got off (and stopped talking out of) my ass and opted to do a nonzero amount of research. I went ahead and evaluated the cost of about ten case study round trips with a bike, and a bike that can disassemble into two 62" boxes each less than 50lb is probably the best route if it's possible. This provides a total of 100 lb to work with and significantly better packing volume. You can review the case studies here if you'd like: Encrypted Sheet. I'm sure there are enough holes in my methodology to trigger someone's trypophobia, so have fun poking.

I called these guys How ShipBikes works to deliver the best least expensive shipping and they said they could ship my ebike with the battery anywhere in the continental US for around $100.00. That was about three years ago.
BikeFlights is their chief competitor and sometimes more economical.
+1 on the bike shipping services. I did have a great experience using BikeFlights a few years ago to send my daughter's bike to her when she was at college across the country. IIRC I preprinted a label and brought the boxed-up bike to a local FedEx (or maybe post office?). Got a box from a FLBS that was headed for recycle bin. The most time-consuming part was boxing up the bike, but not too bad. Added bonus: was able to include some care package goodies for her in the panniers.
Shipping the bike induces additional costs besides shipping -- transportation to and from the airport if you're shameless enough to disassemble and reassemble it right there, which I absolutely am, as well as the cost of receiving a package at a destination where you might not necessarily have access to a receiving address. Either way, I tried it on a couple of these cases and it was consistently more expensive than two checked bags before any additional costs associated with it.

The Velo Orange Neutrino was developed with travel in mind, and they electrify pretty easily. I've done two Neutrino mid-drive builds (Bafang BBS02 and CYC Photon), with 8-speed Shimano IGH drivetrains. The frames have, I think, Tange IRD-compatible sliding rear dropouts (135mm O.L.D.), which might accommodate a smaller rear hub motor and torque tabs.

30MPH, on a packable bike, would be tops I'd go - averaging 20MPH being more realistic. 45-50MPH speeds are, IMO, not feasible or attainable, given the constraints.
That's actually pretty nice. Sadly, the difference between 30mph and 45mph is the difference between ol' Jimmy leaning out his F-250 DiCaprio pointing at me and ol' Jimmy running his F-250 straight over me. In most of the rural environments I'm at, nobody's likely to care unless I impede traffic, then they're gonna' care a whole lot. But this thing fits in *one* checked bag at 62 linear inches! At two checked bags 62" each, I feel like I could find a frame that does the job.
Yes agreed but if you are already carrying a mobile phone, there is plenty of personal information you are leaking wherever you go.
As a major part of your proposal is to save money over renting a vehicle at your destination, you can calculate and compare the shipping costs to the vehicle renting costs to help you decide.
Almost true. Most mobile devices are at all times either (A) connected to the cellular network which can multilaterate their location or (B) running a proprietary operating system that will log either location information directly or nearby wireless SSIDs that can be directly converted into locations via WIGLE and similar databases. I am 100% serious when I say I keep my GrapheneOS device in airplane mode most of the time, usually only connecting to wifi networks whenever I'm not in transit. That's not something I recommend to people or a deeply strange boast; it's just context. I'm just not seriously considering driving a vehicle that runs proprietary software and has a cellular modem when there are other options.
Actually, the reason my username and location are the way they are on this account is because it took 3 tries and a direct message to the administrators to get them to approve an account that was registered over Tor with a disposable email. First two were instantly banned under the assumption they were spambots. ^^;

So at this point I'm left with the question of what are some of the sturdiest bike frames where if you take the stem and the handles and everything else off you can draw a 62" cuboid around the big chunker in the middle, and pack the rest either around it or in another box?
EDIT: Actually, couldn't pretty much any steel non-hardtail work for that?

1. Why wouldn’t you just put the wheels in one box, and the rest in another?
I should've taken your word for this to begin with, lol. First reply had the right answer, but I was skeptical.
 
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We'll I'm not sure how you're going to ship the battery. I called ShipBikes and they can ship my bike and a 20A 52V battery with it.
 
You can relabel the battery packs.

I have fifteen 8Ah packs (5S2P), and twenty something 4Ah packs (5S1P), all same make and model. The only difference besides the case depth is one digit (8 vs 4) on on each of three stickers on each pack, which can be peeled off and swapped between them.

You mightn’t want to push the envelope much further than 8Ah, but 8Ah one’s won’t draw attention. With 5S2P 21700 cells they’re practically the same size and weight of old 18650 4Ah packs.
 
You can relabel the battery packs.

I have fifteen 8Ah packs (5S2P), and twenty something 4Ah packs (5S1P), all same make and model. The only difference besides the case depth is one digit (8 vs 4) on on each of three stickers on each pack, which can be peeled off and swapped between them.

You mightn’t want to push the envelope much further than 8Ah, but 8Ah one’s won’t draw attention. With 5S2P 21700 cells they’re practically the same size and weight of old 18650 4Ah packs.
That is a pretty good illegal life protip but probably one I'll pass on, since packing more batteries doesn't bug me at this stage. Buying them might, though, haha. Maybe I'll go with a cheaper power tool manufacturer than DeWalt for my batteries (since their 20 volters are nominal 18.5ers which means I'm actually bringing 90ish Wh batteries labelled like they're 100s) if I can find 3d print model for the interface. but I don't see myself buying third party unless I've seen someone tear it down. Plus knowing that they're all using the stock labels is going to help me keep my parallel groups at the same charge level.
 
You’re essentially just buying cells, unless you put any value on the integrated BMS.

I’d stick with linear layouts for ease of repair and rebuild.

Unlike this dewalt, which is a nightmare to rebuild.
 

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I'm also buying a case that a TSA agent isn't going to have questions about. That's the main reason I'm shelling out the extra money for drill batteries. I suppose I could buy cheap drill batteries and disassemble them to check the internal cells. If I disapprove, replacing them with decent LiFePos then casing them back up shouldn't be a problem. But I doubt the cost savings of buying cheap drill batteries over OEM ones will offset the costs of labor and a battery welder.
 
Sadly, power tool manufacturers aren't super transparent about the maximum discharge ratings of their batteries, but you can find threads where someone's torn down most batteries. I'm going to have to split this build across multiple paychecks, so if some drill battery goes on sale by the time it's time to buy the batteries, I'll have to redo the math, but right now the most cost effective option is Milwaukee M18 XC 5.0 Ah packs, which, if we take "Lavender Flavour Lube"s word for it, would be able to meet the demands of a 72V100A Sabaton in a 4s3p configuration (unless u/LavenderFlavourLube is talking about peak discharge and the Sabaton's rating is continuous). Either way, I'll probably look for a teardown video and hopefully get a peek at what's actually inside when the time comes.
 
At the very least you’ll be paralleling 5S2P packs, for 20S4P.

100A is a heavy load for 4P. Plenty of cells can do it without overheating, but cycle life is a worthwhile consideration. 21700 will suffer less in this use case, but still suffer. 6P 21700 would be more sensible.

There’s no sense in paying a tool brand premium. The brand you’re buying is that of the cell manufacturer, not the tool company.

For example, Aldi’s house brand (Ferrex) 8Ah and Milwaukee’s HO 8.0 are both 5S2P Samsung 40T packs. There’s a better than fair chance they’re assembled in the same Chinese factory, but that’s irrelevant. The important thing is AUD$248 vs AUD$100. In the US the Milwaukee will be less of a rort, but still double that of other identical batteries.
 
At the very least you’ll be paralleling 5S2P packs, for 20S4P.

100A is a heavy load for 4P. Plenty of cells can do it without overheating, but cycle life is a worthwhile consideration. 21700 will suffer less in this use case, but still suffer. 6P 21700 would be more sensible.
Sounds like we're talking about the same number of parallel groups then -- 3 battery packs in parallel for 6 parallel groups inside the case.

Why 5 in series? You'd have to convert the voltage down to meet the controller if you did that.

I'm definitely not going with any fewer than 12 100Wh batteries, just for range reasons.

For example, Aldi’s house brand (Ferrex) 8Ah and Milwaukee’s HO 8.0 are both 5S2P Samsung 40T packs. There’s a better than fair chance they’re assembled in the same Chinese factory, but that’s irrelevant. The important thing is AUD$248 vs AUD$100. In the US the Milwaukee will be less of a rort, but still double that of other identical batteries.
If I can be sure that they're the same cell while ordering online that's definitely on the table. I couldn't find many aftermarket drill battery teardowns, and if even one isn't the same on the inside as the others, the results could be castastrophic.
 
There’s good Chinese cells these days. Japanese and Korean ones aren’t mandatory.

There is still junky Chinese ones though, and different battery batches of the same model can incorporate different cells, so, yes, you absolutely want to find a great priced battery, buy it, go home, open it, check the cells, close it, then go back to the shop to either return it or buy lots more of them.

You said Sabvaton 72V. That’s 20S. Tool packs are 5S.

The benefits of the 21700 form factor are better power density, heat shedding (surface area), less interconnects, and future proofing (‘cos tool batteries are transitioning to this cell format).

For your application, 21700 4P is equivalent capacity to 18650 6P, and will be lighter, smaller, cheaper, and easier to hook up.

21700 6P would be heavier, larger, slightly more expensive, equally easy to hook up, but provide far greater capacity, run cooler, and have significantly longer life span.

21700 just means cribbing on the 100Wh regulations, but if you can live with that then batteries using these cells are the obvious winner for your application.
 
The benefits of the 21700 form factor are better power density, heat shedding (surface area),

I have no experience yet with 21700 cells, but even a middle school geometry student could tell you that the bigger cell has less surface area per mass/volume. So that's a disadvantage, not an advantage.
 
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