dgk wrote:
On Sun, 16 Jan 2011 18:10:22 -0800, SMS
wrote:
You really want to avoid an eBike where the battery pack is placed over
the rear wheel. It should be in the center of the bike. ..

Poppycock. In theory, the weight would be better placed in the middle,
but I have a Trek with the battery over the rear wheel because Ebikes
are not technically allowed where I live and that makes it much less
obvious that there is a battery on the bike. Since the battery weighs
about 5-7 lbs (my weight fluctuates that much) weight distribution is
not an issue. The Pacific Bikes actually have a stronger battery than
the Treks (10ah to 6.4ah), but the Bionx motor is far more efficient
so the battery weight is low. The Pacific Bikes are 250 watt, the
Treks are 350.

To have the smallest effect on handling, one would ideally mount the battery at
the center of mass of bike+rider. Since that is seldom practical, the next best
location is directly below the center of mass. Battery mounting location becomes
more important with a heavier battery. For small batteries of 5-7 lbs, the
effect of suboptimal placement is small.

Before I got this bike I used to think that there should be some way
to save the energy generated going down a big hill so I could use it
going up the other side. Of course, there's always a light or stop
sign at the bottom of the hill. Well, my bike does exactly what I
wanted..

Unless you descend hills slowly (no faster than, say, 15 mph) or you and your
bike have a high mass to aero drag ratio (e.g. streamliner or aerodynamic
velomobile), you aren't going to get much back from regenerative braking.

http://www.ecospeed.com/regenbraking.pdf

--
Bill Bushnell
http://pobox.com/~bushnell/