Currie-EZip ebike Kit $289.88 - Amazon.com

[stanz]

WOW, when you guys get pissed, you go at it!

$290 for a 24V kit with batteries isn't bad, not my cup of tea, but not a bad price. It's the lowest complete conversion kit other than the off-shore stuff.

If you need a kit without batteries I'm pretty sure there are still some 9C kits available for $249: viewtopic.php?f=31&t=14731

[gogo]

There is a couple in their 70's that live across the street from my parents in AZ. They ride their eZips all over and seem to love riding them.

[icecube57]

wow.. umm some awesome reading skills.

[DrkAngel]

I run my 500w motor at 1500-1600w constant with no incident. It doesn't even get warm. No babying it, 5 mile hills, jackrabbit starts. I do pedal but only to increase my top speed to about 28-29mph or so.

At 500 watts, a 36v hub motor draws approximately 25 amps.
At 1500 watts, a 36v hub motor would draw approximately 75 amps.
That means that your Turnigy 20ah 36v pack would propel you for only 16 minutes, maybe 8 miles?
Your old 5ah Lipo, about 4 minutes, it could take you, less than, 2 miles.

If you are going to make stuff up ... try to be a little more realistic.

[neptronix]

At 500 watts, a 36v hub motor draws approximately 25 amps.
At 1500 watts, a 36v hub motor would draw approximately 75 amps.
That means that your Turnigy 20ah 36v pack would propel you for only 16 minutes, maybe 8 miles?
Your old 5ah Lipo, about 4 minutes, it could take you, less than, 2 miles.

If you are going to make stuff up ... try to be a little more realistic.

LOL... was not aware i was going up against Einstein here. I am going to have to cry uncle DrkAngel!!!

[stanz]

I run my 500w motor at 1500-1600w constant with no incident. It doesn't even get warm. No babying it, 5 mile hills, jackrabbit starts. I do pedal but only to increase my top speed to about 28-29mph or so.

At 500 watts, a 36v hub motor draws approximately 25 amps.
At 1500 watts, a 36v hub motor would draw approximately 75 amps.
That means that your Turnigy 20ah 36v pack would propel you for only 16 minutes, maybe 8 miles?
Your old 5ah Lipo, about 4 minutes, it could take you, less than, 2 miles.

If you are going to make stuff up ... try to be a little more realistic.

Huh? Neptronix said he was running 41.4V, if he is pushing 1500W into his motor that means he's using 36.23 amps, not 75. W = V x A right?

75A at 41.4V would yield 3,105W zoom zoom!

I have pushed 837W through my 500W hub motor when my SLA pack was at 39 volts. If I was running more voltage I could provide more watts, my controller limits me to around 21 amps.

[DrkAngel]

Huh? Neptronix said he was running 41.4V, if he is pushing 1500W into his motor that means he's using 36.23 amps, not 75. W = V x A right?

I have pushed 837W through my 500W hub motor when my SLA pack was at 39 volts. If I was running more voltage I could provide more watts, my controller limits me to around 21 amps.

1. "Watts" rating on motors is a measure of output, not intput. 750 Watts = 1 HP (Horse Power)
2. Output is a factor of efficiency, input watts x 80% efficient motor x 75-95% controller x 80-95% battery efficiency.
(Example: 1000w input x 80% x 80% x 80% = 512w output.)
3. Battery at 41.4v is the full charge of a 36v median battery, thus, 36v should be used as "battery" volts, unless for a very brief, "max output", measure.

[stanz]

My brain hurts, just look at it.

[Nehmo]

I now have the bike, but I didn't get the Currie SLA battery. I used 2 U1(lawnmower) 12Vs in series. It's heavy at 105 pounds. Where did you, DrkAngel, get the cheap Li batteries?

`~- Nehmo

[Floont]

We run our hub motors at 2-10 times their watt rating on here, whereas you have to worry about an additional few hundred watts blowing your eZip motor.

That is crazy!
You are saying that you'all run your 36v hub motors at 72v - 360v!

I run my 500w motor at 1500-1600w constant with no incident. It doesn't even get warm. No babying it, 5 mile hills, jackrabbit starts. I do pedal but only to increase my top speed to about 28-29mph or so.

So ... you run your 36v hub motor at 108v - 115v!!!
I do exactly the same speed with my 37v EZip!
Faster ... actually ... 30+MPH!

Either you have a very vivid imagination,
or you just don't have any idea what you are talking about!

and then followed a little later by...

There is a couple in their 70's that live across the street from my parents in AZ. They ride their eZips all over and seem to love riding them.

(I lowered drkangel's shouting in the quotes above to return some civility to the conversation).

"To each, his own", I say. If you want a simple recreational bicycle like the retired couple referred to by member gogo, then the ezip works well. And if you want a little assist for your commuter bike or recreational bike, then ezip is for you. Obviously, drkangel likes his. neptronix statement made earlier in this thread is close to accurate though. Brush-less hub motors can be over-volted and over-amped far more than brushed motors can.

I have personally over-volted my Crystalyte x5304 hub motor, significantly upgraded my controller with a custom Lyen controller, upgraded the wiring to a thicker gauge and experimented with optimizing the firmware to provide higher current on the controller. I increased the voltage from 72v nominal to 132v nominal and have increased the maximum recorded current from 30 amps to 105 amps instantaneous (50ish constant). So, based on these values I've increased the wattage by approximately 6.4 times from stock (instantaneous) and about 4 times (constant). The limiting factor is now the outdated lead-acid batteries. But notice that the bike still not limited by the hub motor itself. There are many others on these forums that have done more than I have and significantly exceeded 10KW sustained on their hub motors for a power increase of over 5 times the stock value. So, neptronix's "2-10 times their watt rating" may be stretching it a bit, but his statement regarding brushed motors not being able to do even close to that is absolutely correct.

So, once again, "to each his own"!

FA

[DrkAngel]

I now have the bike, but I didn't get the Currie SLA battery. I used 2 U1(lawnmower) 12Vs in series. It's heavy at 105 pounds. Where did you, DrkAngel, get the cheap Li batteries?

`~- Nehmo

Homemade Battery Packs

[icecube57]

.

[dumbass]

I think you can use "SPORTS20" to get $55 off too. You have to use an Amazon credit card though. Coupon should be valid until June 15th.

Noisy motor, but if you don't mind the noise its pretty good otherwise.

True ... The 2008 model was noticeably noisy.
By comparison, the 2009 model was, nearly silent!
Hopefully, the newer models, improved, even more. ... ?

I am guessing that this is a clearance price, on the 2010 model.

I've read that adding a plastic spacer inside the gearbox can quiet it down a lot.

Actually that was my posting to add the plastic spacer in the gearbox. I do not recommend the average person try it. Beside it's really a hit or miss result. I've had great results on some motors and zero improvement on others. Bob

[DrkAngel]

2-10 times their watt rating. Meaning a legal 750w kit Double that is 1500w. 10 times that is 7500w. In no way did he say anything about 100+ volts or 72-360 volts

Volts is pressure, higher pressure = more power.
Volts x Amps = Watts
You can't force in more amps, than the windings will handle, unless you up the volts..

30A x 36v = 750w motor
300A x 36v = 7500w motor - but 36v can't push any where near that through the motors wiring!
30A x 360v = 7500w motor - Might work, if you find some one to build the controller.
But, liable to be a spectacular 4th of July Show!

Only way to up the watts, is by upping the volts or the amps.
Tho, a combination will improve HP, I can't imagine anyone getting 10HP, out of a 1HP motor ... for more than a few second ...
Note: 16ga windings should start to burn near the 50 amp point.

[icecube57]

.

[icecube57]

.

[DrkAngel]

But from a stand still the motor will draw whatever the motor wants as long as the controller current limit isnt hit. In a stall situation or coming off the line the 9x7 motor will draw up to 130A max at 36v at that point the windings can no longer accept any amps because its being limited by the resistance of the windings.

Which would make them red hot!

So the increase in amp does increase wattage output up to the limitation of the winding in extreme cases.

Actually ... in a "lock test", Increase of amps increases wattage input ... motor wattage output is zero! Heat does not count.

[Hillhater]

The only way to increase watt output on a hub motor is to increase the volt input!
Unless you rewind it?

Volts is pressure, higher pressure = more power.
Volts x Amps = Watts
You can't force in more amps unless you up the volts..
.

Errr ? .. have you never heard of the controller limiting the amps ???
a simple change of controller can double the power output from some stock Ebikes.

[icecube57]

OMG THANK YOU! Hillhater is right putting simple and to the point. You can double the amps and double the output but once the motor tops out in speed then no matter how many amps you use both stock and Super Stock are going to have the same output power due to BEMF but off the line power and acceleration you will see an increase in... input power and true output power at the same voltage with increased amps.

[icecube57]

With increased amps there will be increased losses in the windings as heat but there will also be an increase in output power. The stall represents the total power avaliable off the line if there was no current limit as you proceed up the power band the power output of the unrestricted magic controller motor will be greater vs a current limited motor. And it wouldnt lead to destruction cause you cant escaped BEMF in a motor.

[icecube57]

Output profile of a 30A controller and a 100A controller.

Also a plot of not the input power but the True OUTPUT Power.

This is a 9C 9x7 Hub.

Also the hub with the 100A controller has an increased acceleration from 9.8 secs to reach top speed to 6.1 seconds. My god where is this extra power coming from?

Whats this about the motor not only being able to accept no more than 30A.

[DrkAngel]

Errr ? .. have you never heard of the controller limiting the amps ???
a simple change of controller can double the power output from some stock Ebikes.

If ... the motor is deliberately over-regulated?
So ... one function of the controller is to reduce the amperage to a "safe", reasonable level?

Actually, a higher amperage controller will increase power input, most noticeable in the lower rpm region, where it is least effective, where more amperage greatly increases the percentage of damaging heat, and a comparatively minor increase in power output!

[Floont]

...
The only way to increase watt output on a hub motor is to increase the volt input!
Unless you rewind it?

Volts is pressure, higher pressure = more power.
Volts x Amps = Watts
You can't force in more amps unless you up the volts...

Not entirely true. Most controllers limit the current available to the motor. So, if you upgrade or alter your controller to allow the motor to take as many amps as it demands, then (and only then) is your statement true.

FA

EDIT: PS My above correction is also not entirely true, now that I think about it. You must have batteries that are capable of delivering the current that the motor is demanding too.

[icecube57]

I can post the results for a 5303 that will clearly show an upgrade in amps clearly increases output power.

48v and 60v show drastic changes.

[Floont]

I can post the results for a 5303 that will clearly show an upgrade in amps clearly increases output power...

Beating a dead horse my friend.

If the current (amp) restriction is the motor, then and only then is Drkangel is correct, voltage is the only way to increase power. Unfortunately, the reality is that controllers can and do limit current by design (icecube's point). Upgrading the controller or changing the firmware of the controller to allow more current will increase its power w/o increasing voltage. This situation is very common. I am surprised that Drkangle doesn't acknowledge this fact.

FA