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[Crissa]

Nope, you missed my point entirely. Pilots love a low density altitude because it means high lift.

No, I'm pretty sure that's not what low density means.

Low density means low lift.  (It also means low resistance, which is great for level flight).

Low altitude usually (but because of weather does not always, which when it doesn't, it's bad, GIR) means high density.  Density altitude is the property that the density of the atmosphere is by how much is above you pressing down.  Low density and low altitude are literally opposites.

Density altitude is a measurement.  You should never say 'low density altitude' because it comes out as word salad.  It's funny but needlessly confusing because of word order.

*sigh*

-Crissa

PS, I went to Embry Riddle Aeronautical University.

[Doug S]

I don't care where you went to school, you obviously didn't learn what a "density altitude" is.

We're saying the same thing. You just need to look up the phrase "density altitude".

[togo]

> I took my SR/F out for an errand this weekend and got much less range that I expected...

Check out "Zero Below Zero".  It's a book, and a blog, from the good people at Aerostich.

[flattetyre]

Lol, someone may have gone to embry riddle but they clearly haven't read much pilot literature or talked with many pilots because "high(er) density altitude" and "low(er) density altitude" are commonly used, and correct, phrases. What a petty argument, since everyone gets the main point that other things equal, less air pressure = low drag = more EV range.

[Crissa]

This is why you don't hire pilots or engineers to write things.  Highly educated, but very rude when taken out of their specific language.

I explained the proper definition of density altitude and why you shouldn't mix phrasings together.

-Crissa

[Brammofan]

Enough. Chill out and go to your neutral corners. Thread will be locked.

[alko]

I ride in 100+ degrees in summer and down to freezing winter time at speeds around 35-45 mph. I get my best range of 140+ miles when it's over 100 degrees. At temps around 50-60 degrees, my range drops to about 120 miles. At temps 40 and below, my range drops to about 100 miles.
To me, thats a big negative for electric vehicles.
I have a 2017 dsr zf13.

So, some drop in range, but not half like I got.  :-/

Freeway speeds already cut your range in half compared to city driving so in cold weather it will be even worse.

[princec]

https://www.boldmethod.com/learn-to-fly/performance/vx-vy-altitude-and-where-they-meet/
Why argue when the facts are trivial to Google.

Cas

[Doug S]

Or even more on point:

https://en.wikipedia.org/wiki/Density_altitude

[Crissa]

Density altitude is a measurement.  You should never say 'low density altitude' because it comes out as word salad.  It's funny but needlessly confusing because of word order.

Weird.  It's like I already said that.  Notice in the wikipedia article it uses the phrasing 'increase/decrease in'.

What do they think they're arguing?

-Crissa

[vinceherman]

Pull the logs and lets have a look at that whole ride.

I did pull the logs.
Is there an interpreter for the SR/F logs?

[domingo3]

Soooo, anyone want to talk about temperature impact on range?

 I ride a Zero FXS 7.2 and can make a 44 mile commute when the temperature is below freezing.  All but 3 miles is at freeway speeds 55-65 mph.  Only once did I not make it.  It was 22 degrees and when I was about 2/3s of the way there with over 50% SOC I started going a little faster.  At about 40%, SOC started dropping faster.  Even though I slowed down as much as I could 35-40 mph, SOC dropped as much as 5% per mile.  At least with my bike, I think the lower half of SOC is less than the upper half SOC.  In the summertime, it's no problem to make the whole trip above the speed limit as long as I'm not going WOT for extended periods of time.

Sorry, I don't believe that there is an SRF parser.  See https://www.electricmotorcycleforum.com/boards/index.php?topic=9684.msg85854#msg85854 .  That was a couple of months ago and I don't really track the SRF threads, but I don't believe it has changed.  Do you have a cooperative dealer you can send the logs to?  I doubt anyone will give you the parsed results, but they may be able to give some summary information.  I would think that the drop in range that significant would be considered unusual enough to justify them looking into it and responding.  At least you'd get something documented that you had brought up the concern early on in ownership, so that if the issue comes back with a vengeance next winter, they should investigate a little more thoroughly.
 

[Crissa]

I have encountered this where the lower half of SOC will wear away much more quickly at 40mph and above.  I have gotten 10% per mile at 70mph with the weather being 40-50F.

-Crissa

[Skidz]

I ride all year round in the Netherlands and on my daily commute it fluctuates about 10%, with temps between -5 and +23 average. What really makes it fluctuate is the wind speed and direction, and how annoying the speed limits are that particular day
I have done some 5C/41F test runs, and I will conduct the same runs in the summer for comparison. Please hold 4 months

[Richard230]

I visited my daughter on Wednesday, riding my usual route at my usual speed.  However the temperature was 65 degrees F that morning, instead of the 45 degrees F the last time I took that trip.  I arrived at her home, 37 miles away (about 1/3 freeway speeds), with the SOC showing 72%.   Making the same trip at 45 degrees showed an SOC of 67% when I arrived that day.  It sure seems like cold temperatures do make an impact - at least on the SOC calculation.

However, I certainly will agree that riding into the wind at high speed can really suck the electrons right out of your battery pack.