On Sat, 02 Nov 2019 11:37:59 -0700, wb6dwp wrote:


(Apparently electric motors like to spin fast and are more efficient at
high rpm.)

This is why I've only vaguely followed e-bikes for decades. They were of
no use to slow riders. The only result of riding slow would be to burn
out the batteries from high discharge rates.

The there are lots of great battery articles and howtos, etc. there as
well. The 21700 Tesla Li-ion cell appears to be making inroads along w/
the usual 18650 battery format technology.

Pricing will be interesting as a new local lithium miner has just moth
balled their mine claiming lack of demand. The last time I priced lithum
batteries for a project, it was $30K for lead and $300K for lithium, if i
could get them. The usual battery snake oil seems to have shifted to
thier sale now.


A few years ago during the latest gas crunch I thought I saw $5/gallon
gas on the horizon, so I bought a mid-drive kit from an Australian
company called "Elation".
250W motor, 10 AH 48V system. They have since gone out of business.

.......
I find the 250watt motor will give me a steady 13-14mph or so on the
flat just for how it performs. The elation kit was throttle only, hot
pedal assist.

Over here, the mania, including bicycle bodies, screams pedelec only, but
a reading of the legislation does not say that. which is why eleation
might have shut up shop as the various states have now adopted the same
laws across tha nation,

(a lot of the European offerings also appear to be pedal assist only, no
throttle. Some have throttles also, I think..

The hint on pedelecs was to use a lower gear so the sensor that drove the
motor was fooled by the chain ring rotating. That was in reply to someone
who posted on a local forum that they had pushed(walked) a pedelec hire
trike for miles whenthe chain broke .He was told he should have just sat
on it and rotated the pedals.

That advice/hint would depend on the sensor still being based on crank
rotation and not some sensor pedalling

Anyway, lots of fun reading at "electricbike DOT com".

Sounds like a very useful site from your comments. Thanks.