Just for fun

[OneEye]

myelectricbike,

One more thing,

Does the regenerative controller freewheel when you want it to, or are you always pedalling against the motor if you are not putting in power from the batteries?

-Mike

[OneEye]

myelectricbike,

My understanding was the power rating limits of the US law are for continuous power, not peak.  If I'm right (it's been known to happen) running at 1000W on hills with a slightly modified 500W motor (changing the leads as you describe) would still be considered a street legal "bicycle".



BrandNew:

The 20" wheels you need for your recumbant should have more torque and less top speed than the 26" wheels.

[myelectricbike]

250-300, however, the initial recharge times greater than 3 hours may have been due to breaking the batteries in since this requires many, many cycles. Degradation was not one of the factors I included when I first started recording data. Future records will include accumulated millage. There should be a typical degradation curve though somewhere for 12v, 12ah SLA/AGM technology if only I can ever find it.

[GoldenMotor]

You can switch off the power to the motor, the motor will become freewheel even though you are using a regenerative controller.

[OneEye]

I ran across an SLA/AGM degradation curve a few weeks ago, but I can't remember where.  It said the "sweet spot" for getting the most total energy into and out of a set of batteries was to run them to 20% discharge.  It was also mentioned that a 300 cycle life is typical for 50% discharge.  Deeper discharges drastically reduce overall battery life.  I read somewhere the high amp draws of e-bikes can also cause some sulfation regardless of overall state of discharge and this was a factor in why e-bike users rarely get to the magical 300 charge cycles they may be expecting.

[myelectricbike]

Well it does make sense that the high power draw of an ebike motor with the throttle fully depressed, squeezed or whatever would drop the voltage temprarily below 12.7 to cause sulfation but you'll have to ask a scientist about this (or maybe a high school student studying battery life - try the Wikipedia!)