DrkAngel

OEM
The eZips, Trailz etc., have an oem 15-16mph capability, with some slight assist to ~18mph.

16T ACS Southpaw Mod - $20
Simply replacing the oem 20T motor side freewheel with an ACS SouthPaw 16T.
This increases speed to ~20mph, a 25% increase.
Torque is reduced 20% at 0mph, but loss decreases till torque actually increases at above 10mph!

11T Motor Sprocket Mod - $18
A "simple" regearing.
Merely replace the oem 9T motor sprocket with the 11T.
This will give you a ~25% speed increase.
A reasonable expectation of ~20mph - motor only.
OEM chain length works!

12T Motor Sprocket Mod - $24
A "simple" regearing.
Merely replace the oem 9T motor sprocket with the 12T.
This will give you a 33.3% speed increase.
A reasonable expectation of 20mph - motor only.
With some assist to 24mph.

13T Motor Sprocket Mod - $18
A "simple" regearing.
Merely replace the oem 9T motor sprocket with the 13T.
This will give you a 45% speed increase.
A reasonable expectation of 22mph - motor only.
With some assist to 26mph.

15T Motor Sprocket Mod - $12
A "simple" regearing.
Merely replace the oem 9T motor sprocket with the 15T.
This will give you a 66.7% speed increase.
A substantial assist of 25mph - motor only? ... possibly.
With some assist to 30mph.

FMB42

Nice white paper report DrkAngel!

The "standing start" decrease in torque would be perfectly acceptable with me due to the fact that I'm a "peddle it to get going" type of e-bike rider.

DrkAngel

Of course ... you could add a 12T or 15T mod to the 16T ACS mod.

But you must expect to provide substantial pedal assist, or you are liable to be sadly disappointed.

16T + 12T = 25mph (Some assist till 30mph)

16T + 15T = 30mph? (Some assist till 37.5mph)
Might be victim to a negative return on speed! (motor only)
Ideal for the cyclist capable of constant and substantial pedal assist.
Even with the 11T 7speed freewheel, assist past 30mph would require upgrading the front sprocket from 44T to ... 52T? Simple upgrade.

bluegoatwoods

Hello, DrkAngel.

I recognize you from es. You're helpful to folks over there. I'm glad to see you here.

DrkAngel

DrkAngel

Great simple upgrade for eZip - iZip external non-hub motor.
13T Sprocket Upgrade - $18 includes shipping
Plug-n-Play - except you will need longer chain


Good fit, good alignment, just lengthen chain and all set to go!
OEM eZip top speed @24V w/9T sprocket = 15mph.
15mph / 9T x 13T = 21.66mph (20mph USA "legal" - reasonable expectation)

I emailed "Jon", "Contact US", requesting a quantity purchase with shipping discount.
Was sent PayPal Invoice.
Very good shipping discount on quantity = 4.
$50 for 4 = $12.50 each shipping included!

Mabman

DrkAngel, a friend has a Currie bike and got a 24v duct tape battery for it. Upon hooking up the wiring, with an inline fuse, it will go about a 100 ft. and then shut down. If he takes out the fuse and puts it back again it will do the same thing. I am thinking it is a controller issue but am not familiar enough with the Currie system in regards to the controller? Any help appreciated and thanks in advance!

DrkAngel

Sounds like ...
Battery is too small?
Full throttle drains too fast,
voltage sags below controllers LVC (Low Voltage Cut-off),
LVC disables controller,
removing fuse resets controller.
1. Test by moderating throttle ... a very gentle, partial throttle slowly increasing ...
2. Place voltage meter on battery, observe voltage sag as you increase throttle. Shutdown should continually occur as battery "sags" to some specific voltage.

DrkAngel

Just finished and am testing the eZip Trailz with the 11T motor sprocket mod.

Purpose is to upgrade the 15~16mph capable eZip to 20mph "legal" capability.
2013 eZip Trailz LS @ 25.9V Li-ion, as testbed.
Swapped Shimano 34-14T 7spd for Sunrace 34-13T 7spd.
Most impressive is that the 11T is a plug-N-play replacement for the oem 9T sprocket.
Same chain, no alignment problems!

Excellent!
Cruising speed varied from 19mph+ into wind to 21mph with a fair tailwind.

13T at 22-23mph pushed my 25.9V 26Ah Lipo battery build harder than I liked, and outstripped comfortable pedal assist.
11T at 20mph reduces battery drain, allows more comfortable pedal assist and extends range greatly.

OK ... yes, this bike was upgraded to a 24-36V capable controller, so I can use 33.3V-36V battery ... if I "need" 24-25mph speed.
11t motor sprocket mod is nearly identical gearing to the 16T wheel freewheel mod.

[attachment=0]11T.jpg[/attachment]

gngebike.com now stocks 9T, 11T, and 13T sprockets for the eZip motors!
These sprockets are a plug-n-play fit, no mods necessary ... except for chain length ...

- $18/shipped

DrkAngel

11T and 9T now available from USA.
Replacement key also.
electricscooterparts.com

11T Sprocket - $14.96 + shipping