My partner has become worried about all of the reported e bike battery fires. Perhaps too much time has been spent on u tube videos of these occurrences.

so because most of the solutions to these fire issues have simply failed in any independent tests and
I also like to charge my batteries off the bikes & inside my home (for theft security and away from freezing temps).....

so in response....
I only use stock-brand name manufactured batteries.
I use a luna charger that can limit the charging input to 1 amp and to either 80/90 or 100%.
I charge my battery in a welders toolbox that's been fully lined with a 1 inch layer of fortified & re-enforced concrete.
That tool box is internally vented through the wall to the outside with an insulated 3/4  black iron pipe.
The area immediately around this tool box is protected by a fire proof hardi board.
Have a furnace turbine fan run air handler beside it that is set up to automatically direct vent any fumes to the outside that can escape from this fire vault.

probably over kill but I guess that's what most insurance turns out to be.

Has this e bike battery thermal run away issue been a concern for other rad owners and if so what has been your solution for it?

The 250 to 750 motor core swap will not be visible.

The 750 core how ever has now been modified in the last few months and now looks like the older cheaper Rad specialty cores that many of the earlier videos complained about. In their defense, Bafang claims that these new cores are now lighter and more efficient. Swapping my core from 500w to 750W definitely improved the power band especially in the upper ranges. Just don't make my mistake I did of using an electrical lube to better waterproof the motor connecter as that product can electrically isolate the male and female brass connecters from allowing the full voltage to the motor.

The biggest noticeable improvement though will come from the 35A controller swap...But..If a policemen knows his e bikes, there is a pretty big visible size difference between the size of a stock controller and a 35A controller upgrade.

Update.

I just received a bill today for an additional $57.30 in Brokerage charges for that same motor that UPS previously said would cost me $98.00 in brokerage fees before they could deliver it to me.
This notice warned me that this new payment was now due, and if they failed to receive that payment by mail by Dec 13/22, a 5% late payment penalty would be added to it.

Before complying, I called them up to see if this was a legitimate bill from them, and they confirmed that it was their address. When I asked them to check that amount through my tracking number, they found that it said that all fees on this delivery had already been paid before it was delivered.
They then said to just ignore this latest bill.

It made me wonder how often they ever returned brokerage overpayments.

Latest update.
Well, it looks like my motor core performance issues with the area 13 750W update might have been self-induced. 
My motor has been steadily improving over the last couple of days and Kyle, upon learning of my problems surmises that the dielectric grease that I waterproofed my connections with, was also insulating, to some extent, the motor to controller connection.
He said that he has seen this same problem many times. I guess that with heat and vibration, any grease between the connections is wearing thinner and is now allowing better conductivity.

He also says he has seen numerous connectors destroyed through the application of dielectric grease.

Yeah, if you are going to be riding enough to discharge your batteries back to a 70 -80 % storage charge, a rotating of the batteries on your bike would also allow you to condition each battery every couple of months over the winter with a recommended 12 hour conditioning charge.

@JTK77
That is one beautiful bike.

My Rad Rover 1 is a step-thru that limits some of the battery position options that you are utilizing. I typically get 140 to 145 km on a charge from my two integrated stock batteries, with an average speed of 23 kph and 95% on pas 1.
The weight balance on the bike is a bit too rear heavy, which when set up for a cruiser-styled ride makes wheelies something to watch out for along with potentially harmonic front wheel shimmies when taking your hand off the handlebars while riding.

@rjp
The invoice on the area 13 box that my motor core arrived in says that it is a 750Watt Fat Bike Hub Motor Core 175mm OEM
which means it's probably not a Bafang part but a manufactured substitute by another company to address a shortage in these popular sized cores. It's been confirmed by Kyle that he sourced out this Bare core to another supplier to mate up to Rad Powers needed spec's to address a supply shortage.

My complaint about my particular replacement 750W core not being noticeably stronger than my original Rad Rover 500W core, probably doesn't apply to Electro Bike world's 750W full Bafang motor that you were thinking of buying.

@ rjp
Yes the core marked "new" on the 48 - 60v 750w Bafang geared rear hub motor ad from Electro bike world looks
identical to the core I received from area 13.

I also wonder why no one else has posted about this if this core change has been in effect for  2-3 months.

I've been a bit of a fan of Citizen Cycle and have followed his adventures until he finally had his fill of Rad Rovers and moved on to other brand favorites. I loved how he just jumped into e-bike modifications with nary a care.

I too have run over 1600W through my Rad with seemingly no detrimental effects...except for that one time when I foolishly accepted a challenge to race up a very steep & long incline, when my battery was about 1/2 full and about 30 seconds into it, the bike completely shut down for about 10 minutes.  My bike is also pretty heavy with Tanus armored tires, a wooden lock box on the rear rack, heavy duty locks, an extra battery, 35 A controller in a waterproof box, electric air pump, tool kit, cloud nine seat and a thudbuster seat stem suspension system,  not to mention my usual 195lbs. If I crack the throttle now a days, I usually only do it to make a traffic situation safer and then only for short bursts.

Citizen Cycles along with Boltons & electric e bikes have all done impressive videos showing the before and after results of up grading a Rad with a 35 Amp controller and a full 750W core change. I am still waiting for Kyle to get back to me on their new "improved" Rad Cores to see how this dismal core swapping result might be resolved. I don't know if this present cheaper rad motor core is just a temporary thing while full 750W motor supplies are in short supply. Up until this last order, I found Kyle at Area 13 to be helpful and effective. Expecting much of a response over a business busy Black Friday though will be unlikely.

Thanks  @ JimInPT
I upgraded with Boltons 35A controller & LED a few years ago and was quite happy about the increased performance. Today, I took out my 500W core and put in the Area13 replacement 750W core in my bike. Both cores looked identical to each other and an afternoons worth of testing, showed no difference in power or top end to each other, except that my LED no longer seems to reliably register my speed. I tried all 6 of the P2 wheel speed settings to no avail.
This contrasts pretty dramatically from just about everyone elses videos of such a motor core upgrade although those videos all seem to have been done at least a year ago when the cores supplied were much more physically robust and those installing them described them as Bafangs true 750W cores.

If this was a situation where my original motor had died, I'd probably be grateful just to have my bike back on the road again.
Instead I have spent a lot on a product, shipping, brokerage fees, taxes, a cassette & specialized tools and my time.... to end up with a bike that is now less effective than it was.

One limitation to stem rise on my bike was that my handle bar electrical and brake lines became more stressed the higher I raised it.

I'm 6'1, and on my RadRover, my solution turned out to be with a stem addition that raised the handle bars up 3'' and the moving of my seat as far forward as possible. This created an upright cruising position that was easier on my back and forearms while providing a more leisurely posture.
A cloud 9 seat with springs atop a thudbuster LT suspension also helped.

Hmmm.
I have also learnt that unless I pay any increased claims for more money needed while it is in transit, the drivers will usually just say that no one was home for the delivery and directly drop it off at the local post office with payment owed release forms. I guess this saves them time and allows for a quicker turn around time.

In this case, what they asked for while it was in transit, that they called "duties" turned out to actually be Brokers fees & taxes.

Under duty, there were no charges.

After sitting on the sidelines about upgrading my 2020 Radrover step thru from a 500W hub motor to a 750W, and watching many of the videos favorably comparing Bafangs full cased "true" 750 W hub motor cores over Radpower's original 750 W motor cores, I ordered a replacement from one of the companies that did such a comparison.
When it arrived, the new motor core surprisingly looked identical to Rad Powers's original version. When I complained about this to the supplier, they said that the core that they sent me has been specifically made for the Rad Rover plug & play upgrade and although it looks smaller, it just has more windings within it. They said this was partially done to reduce the motor's weight.
All other motor suppliers now seem to also only be offering this partially cased replacement core. Supply chain limitations, I guess.

Since all the side by side comparisons that I can find were actually between the Rad powers original motor and Bafangs fully cased "true" 750W replacement versions of the same, has anyone here tried out the new smaller replacement cores and if so, what was your impressions of it.

I was just told that I owed an extra $98.00 in duty on top of the normal taxes and shipping costs through ups to bring a $350.00 Bolton e bike motor core from
California to British Columbia.
Am I just cheap or does that seem like a lot?
Any other Canadians had these percentages of duties levied when ordering from the USA?