flecc, I work out that for my daily 10 miles, I would only need about 3 to 5 AHmax - should I buy a bike with a lighter and smaller battery? or save myself a lot of money buying a steel frame e-bike?
I am a strong believer that in certain applications i.e. daily commutes, only carrying a battery of the capacity/weight required is the way ahead. My EBrompton weighs 14kg with motor and controls on the bike. I could probably get that down to around 13kg if I used lighter tires and a two speed setup.
Bag with battery and controller connected via umbilical 2.5kg.
Total all up weight is 16.5kg. Worth noting that this is ready to go with lights and available luggage space etc. Once you add racks, luggage, locks etc to your Ebike that is going to add considerably more weight.
Mine is not light for any other reason than I carry it into and out of my office every day (no heavy locks to carry) and shops if needed. My A123 battery is only 1kg and gives me my 10 miles round commute through Cambridge. I have a charger at work if need be.
There are many other applications for example a 20-30 mile commutes on main roads etc where my bike would not be the best option. I do have a second battery now though and would carry that when I wanted to double the distance travelled.
Remember you need to include racks, luggage, bike locks etc to your overall weight
Regards
Jerry