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This is your experience when driving at interstates speeds?
~85% of the time. Spring time. No Heating or Cooling?

Oh well, I asked for opinions....
Yes. Speeds over 65 greatly reduce the range of the Bolt. And if you don't have LRR tires on all four corners you are already paying a penalty for that at all speeds.
 

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Yes. Speeds over 65 greatly reduce the range of the Bolt. ..
Yes, and speeds over 55 reduce the range compared to 45, and 45 is worse than 35, etc, etc,
65 is not some magic number in Boltdom.

There is some speed where the '3.9 mi/kWh' default comes from.
That speed used on a 59掳 day, sea level, 29.92 inHg, no winds. Oh, and LRR tires!
You have to have some standards to come up with that default.

Never mind.
I'll live with my 177 mile GOM and keep speeding and wasting all the Free Electrons I mainly use to commute with.
I could take the slow, back road way home and spend much more time commuting to raise that GOM. Nah...;)

Did I mention I routinely bump the 92 MPH limit when 'repositioning' myself in the left lane?:cool:
Just seems 62k miles is too soon to lose 10% capacity compared to other Bolts....
 
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65 is not some magic number in Boltdom.
Disagree. My Bolt hits the proverbial brick wall at around 70 mph as far efficiency goes. Drag coefficients aren't a constant over the whole speed range, after all.
 

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Disagree. My Bolt hits the proverbial brick wall at around 70 mph as far efficiency goes. Drag coefficients aren't a constant over the whole speed range, after all.
What you are seeing is the aero drag going up enough to clearly outstrip the mechanical, rolling, and background electrical loads. Aero drag increase is exponential from zero on up.
 

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2019 Chevy Bolt LT, Cajun Red
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This is my Recall Experience:

View attachment 35601

I was really hoping the new SW was going to reset my GOM brains,, OR,,
report to the Mothership that all is not well in this battery pack.
I was hoping for a faulty cell/module to self-report with the new SW and a repair would be initiated.

I know the GOM is not battery capacity display.
I know I don't flog it too hard and this time of year HVAC is not used much at all.
Non LRR tires in the front.
This car is ~85% at 65-75 mph on the interstate.
But still, this seems low.

What are my options?
Complain to the dealer and pay a $100 'Diagnostics Fee'?
I had this low range complaint noted when I dropped it off for the final SW load.
Any suggestions from you guys?
that screen tells us very little after you just reset the mi/kWh.
let it ride for say 500 normal driving miles and post again, then maybe we can help.
But it sounds like you simply drive inefficiently. Why you claim degradation I do not know. 177 highway miles with some ac use and 75 mph+ sounds about right to me. 3.0 mi/kWh? is that what it showed before you reset it?
 

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Yet your photo shows it drawing 3kW. You can gain 20 miles of range on the GOM by turning off the AC.
You Canadians are funny!
1. That was after a 'sitting in the sun, on a hot day, charging all day' start up. AC was getting after it briefly.
2. How many 'loonies or toonies' would that save me? Answer: None. Free Public Charging.
3. You Canadians are funny. It gets hot down here!

I'm sorry, but I really cannot let this pass uncontested ...
The drag increase is quadratic. Exponential would be c^speed. :alien:
I thought it was Velocity虏, but do go on!
Nope. Smooth exponential curve, however it's calculated. Aero Drag. No 'knee' or 'hitting the wall'.
 

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It is the knee of the total drag curve, not of the aerodynamic drag curve.

View attachment 35668
I just read another tech article on rolling resistance in road bike tires.
What is the best size and pressure, etc. Lot's of new thinking, no?
That article claimed rolling resistance increases linear with speed because you are compressing the contact patch more often with increasing speed.

And this Aero drag curve is not X虏 or quadratic.
I know you didn't make this plot, and I'm pretty sure it's wrong.
RR is higher than Aero until ~55mph? Doubtful. Maybe for a Semi truck with low tire pressure....
 

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RR is higher than Aero until ~55mph? Doubtful. Maybe for a Semi truck with low tire pressure....
Why doubt, when it is easy to calculate ?

Using Si units
m - mass
g - 9.8
v - velocity in m/s
茠 -- rolling coefficient of friction. Garden variety tyres are ~ 0.009
rho -- air density

m*g*茠 = Cd*A*v*v*rho

----
Gjetson is right about the knee when total forces and loads are considered.
 

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茠 -- rolling coefficient of friction. Garden variety tyres are ~ 0.009
This part. Is it a linear increase with speed?
And what is 0.009?
 

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This part. Is it a linear increase with speed?
And what is 0.009?
It is a dimensionless coefficient, like Cd.

"It is very easy to calculate the coefficient of rolling resistance with a low speed coast down test like this one. If the cart rolls 1500cm from a plateau of 15cm height the Crr is 15/1500=0,01

All tires roll about 750cm at 29psi and therefore have a Crr of 0,02 that is twice as much as the 0,01 that I have used in my former calculations. Even when inflated to 44psi it does not get much better than 0.017 and that is 2,5 times the Crr of a low Crr car tire."


My dream is to have a streamlined, electric recumbent motorbike before I die.
 

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My dream is to have a streamlined, electric recumbent motorbike before I die.
If it's electric, why does it need to be streamlined and recumbent? You're already saving the huge majority of energy just by riding a bike instead of driving a car...
 

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This part. Is it a linear increase with speed?
And what is 0.009?
The result of m*g*茠 is a force (Newtons in SI), and Force * velocity is power (watts). So power increases linearly with speed but work remains constant per distance.
A typical tyre value. It is a scalar because m*g is a force.

If your context is Wh/km then drag from RR is constant and aero losses increase quadratically
If your context is Power as a function of speed then RR drag increases linearly and aero drag increases cubically.

If you want to see how the algebra works out, use
F(orce) = m(ass)*a(cceleration) -- Newtons second law
W(ork) = F*D(istance)
D/T(ime) = velocity

---
In case you are wondering, speed is a scalar and velocity is a vector. I get lazy and use the terms inter-changeably when the context is clear and the result is the same.
 

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If it's electric, why does it need to be streamlined and recumbent? You're already saving the huge majority of energy just by riding a bike instead of driving a car...
Because motorcycles are horribly inefficient, and uncomfortable, for a start. A typical sit up touring bike has as much aero drag as a car, and the seating position is very uncomfortable...not as bad as a crotch rocket, but still much worse than a semi-recumbent position, like a sportscar.

If you notice, there are no 200+ mile range electric bikes, except this one.


 

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Because motorcycles are horribly inefficient, and uncomfortable, for a start. A typical sit up touring bike has as much aero drag as a car, and the seating position is very uncomfortable...not as bad as a crotch rocket, but still much worse than a semi-recumbent position, like a sportscar.
So... the reason is comfort and range?

I guess my biggest concern is just that recumbents are a lot less visible than upright bikes and also have less visibility for the cyclist due to the lower line of sight. I think I'd be too paranoid to be on one in mixed traffic. I've caught myself failing to spot even an upright bike on a conflicting course because my brain is programmed to watch for cars. And that's when I've been cycling myself!
 
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