Speed vs Range
Everyone likes more speed!
Well ... most everyone.
What most don't realize is the cost of more speed.
Pulled from the ebikes.ca simulator, I noted the various ranges supplied at different speeds.
Generic Mountain bike - motor only.
665w peak output motor w/48V 10ah battery = similar to a 24V 450w peak output eZip motor - pushed to 36V 675w peak output motor.
10mph = 46 miles range
15mph = 30 miles range
20mph = 20 miles range
25mph = 13 miles range
30mph = 8 miles range
Wow! ... calculator - click click click ... Every 5mph increase in speed decreases range by 33%!
Most are shocked at the affect wind resistance plays.
Wind resistance is the major factor, but road load, tires, drive train etc. also contribute.
Makes me reconsider a lot!
Do I need 30mph capability? Nice to have it but ... don't need
to use it! - OK! - Still a go.
Road Style bike with high pressure tires and crouched position? - Working on one!
Motor only, crouched behind an Aerodynamic fairing? Sounds almost essential - for sustained 30mph! - Battery pack mounted between bars and fork is a partial fairing. I'm sure I could easily enhance that!
Fortunately, I tend to cruise at 15mph, commute at 20mph with only very limited bursts nearing 30mph.
I'm even considering not upgrading (choke) my latest eZip Trailz LS.
(I use 3 eBikes + latest eZip, + building a road version and an eTrike ... also.)
OEM configuration is limited to 15mph in TAG (Twist And Go) mode and ~10mph in PAS (Pedal Assist System) mode.
Well, not upgrading, till after I run a range trial with my prototype 22.2V 40Ah pack.
I will add high pressure 1.75" tires for less rolling resistance and comfort seat and suspension post ... <15mph range trial might mean 5+ hours in the saddle!
A differing summation of watts required for a mountain bike to maintain various speeds.
5mph = 22w
10mph = 68w
15mph = 163w
20mph = 333w
25mph = 601w
30mph = 993w
35mph = 1532w
40mph = 2247w
45mph = 3147w
50mph = 4280w
from ebike.ca simulator
30mph requires almost precisely 300% the energy as 20mph.
Of course, it does not require 3x the energy per mile.
163w/15mph = 10.86wh/mile
333w/20mph = 16.66wh/mile
993w/30mph = 33.1wh/mile
Still 30mph require 2x the energy per mile, or ...
Same ~36V 10Ah battery ...
15mph = 30+ mile range or - 92.08 miles per kWh = 6 hour cruise time
20mph = 20 mile range or - 60.02 miles per kWh = 3 hour cruise time
30mph = 10 mile range or - 30.21 miles per kWh = 1 hour cruise time