20mph "Legal" Limit (USA)
Anyway
10mph = 46 miles range
15mph = 30 miles range
20mph = 20 miles range
25mph = 13 miles range
30mph = 8 miles range
The 20mph USA "legal" eBike speed begins to look more "reasonable" than it did originally?
I have multiple "compliant" eBikes:
Comfort Cruiser
2009 eZip Trailz LS (Low Step)
No pretenses, 20mph limit on a big tired, big low slung suspension seat, full upright position.
Typically I "cruise" at 15mph and "meander" even slower.
Designed for motor only, but I do apply some assist getting up to speed and on hills ...
Dumped the 24V 10Ah SLA batteries and packed 25.9V 25.92Ah LiPo into the oem eZip battery case.
The battery upgrade, combined with the 16T upgrade provides a reasonable ~20mph.
The Commuter
2008 eZip Trailz
Designed to commute at a sustained 20mph.
29.6V 31.2Ah homemade Li-ion battery pack.
16T upgraded drive gear.
Smaller, higher pressure, Kevlar belted, low RR tires.
Proper pedaling position seat.
Designed for continuous pedal assist, motor only 20mph+, reasonable pedal assist provides better range or a comfortable 25mph.
Safety gear includes reflective tires, strobe headlight tail and turn signals, (mirror is mounted on helmet).
Snow Beast
2008 eZip Mountain Trailz
Winter only, designed to mush through slush, snow and ice.
OEM 20T gearing but upgraded from 24V SLA to 33.3V 31.2Ah Li-ion for a ~20mph capability with a substantial torque increase. (1st upgrade 37V 20.8Ah Li-ion battery replaced for better durability and 20mph legality)
Homemade studded tires ... front tire swaps between mountain tread and sheet metal screwed mountain tire, dependent on road conditions. Rear tire is a used carbide studded tire, drive wheel wears steel studs too quickly. Home made studded provides better traction than the carbide.
I do assist for extra umph, when needed,
When really icy-nasty ... I lower seat and ski my feet.
Might have gone overboard with this one ...
Then I went way too far ...
So 20mph is OK by me ... though I might push the limits.
By tuning motor wattage, amperage and gearing, I can limit motor only speed to the "legal" 20mph, but provide substantial motor assist above 20 mph.
Even modest pedal assist might provide 25mph+ speed and some assist is available right through 30 mph!
I do have a
Haro 700C 24speed I intend on gearing for 22.2V 43.2Ah battery that provides 20mph capability ... might be a switch that "TURBOs" to 44.4V 21.6Ah (providing 30mph+ capability), 48-11T sprockets allow 30mph+ pedal assist at 90rpm.