ebike performance in 110-150 degree and 80%+ humidity?

curious what performance concerns there would be with operating and maintaining an ebike (dd or geared) in both an extremely humid and hot atmosphere?

I recall that rain isn't so much a problem for hub motors as is the temperature differential wicking in moisture into the hub... if everything is hot as balls.. would this be a non-issue?

also.. what implications might there be on the operation/care of a battery in these conditions?

150 degrees is too hot, for batteries, controller, motor, and me.

Seriously, it will work but you better plan vented batteries and controller. Motor will overheat quickly if you abuse it. I would build a cooling system.

I use 4 nissan leaf batteries in an air cooled scheme They are in a aluminum sided .Screened frontand rear enclosure where a motor cycle fuel tank would be.
I usually ride in the cooler part of the morning. After noon temps are around 110 F here.
I use dual 1000 watt OIL cooled hubmotors.
The rear motor is for normal riding . It does get hot on long uphill climbs.
The front hub motor is used to help the rear motor on long uphill climbs, or to totally replace it when the rear one overheats.
Or both to take off like a bat outa hell.
The humidity here is near zero . Except for the MONSOON rains once a year.

I am also trying a down rated mxus v3 with ferrofluid and spring radiators around the hub.

No real issues with 110f, or humidity. Yes,, since your motor will be 200f inside, and outside only 90f lower, it will cool less fast than if it was 150f lower temp outside.

But as long as your motor is not overloaded and or overpowered, it will just reach an equilibrium temp inside below 250, and won't cook the motor. The only effect will be that your motor will warm up to that max temp quicker. That's fine.

The battery though, will not enjoy being parked where its 150. South side of a building, in the sun, not a great place to leave it for long. And particularly, do try to let the battery cool to body temp at least, and charge it, in a place no more than that temp. A hot garage, or south side of the building in the sun, is no place to charge your battery, or let it sit for a long time.

On the road, running at ambient temp, or slightly higher is fine. If your battery is getting all hot as you discharge it though, that's a different story. Your are pulling too hard on it, and it won't like that. But running it or parking it in 110 conditions won't harm it. Running it will cool to near ambient temp, and parked in shade it won't fry in the sun like an egg on the sidewalk.

On a hot day, the battery will actually perk up, have less sag and go farther, compared to a cold winter day.

Since I live in California, where it gets hot during the Summer months, I put my controller in front of the down tube, where it gets plenty of air flow to help cool it down/prevent it from getting too hot.

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