Rydon said:
I disagree RTIII!
That's fine, but the only thing I "got wrong" was making my statement a little too general. For example, in the context of the TSDZ2, what this thread is all about, there is no such thing as tearing up drive trains. We're talking 750W, max, that I've ever seen. And, you can go too far with anything, "all things in moderation", but I also wasn't wrong about batteries degrading. Size a battery perfectly when new and you'll be unhappy when it's older. That's a fact based on chemistry and experience. Note that I never recommended a 15 lb battery - or a 3lb one either, for that matter.
Also, based on your comments, I gather you haven't much experience with the TSDZ2. For example, I've been on a number of rides of 20+ miles over a mix of steep hilly terrain and flats and figure I can get a theoretical 96 miles or thereabouts out of my 11.73 Ah "48v" pack. I could do such a ride on a lot smaller battery! Yes, my battery may seem like overkill, but then, possibly unlike you and most others, I'm building my bike out with:
- "running lights" (side lighting)
- turn signals (two in front, two in rear, plus possible trailer)
- car horn (when a bell is just not enough!)
- a trailer hitch wiring harness to provide tail, stop and turn lamps to the trailer
- inverter for automotive accessories so I can bring gadgets on picnics and so forth
And I want to be sure it all will be working when I get home late, after dark after being out all day and not run out of juice short of home. Oh, and it's always good to NOT run your battery completely flat! I make it a habit to try and never go below 50%, or 80% as a worst-case - they live a lot longer that way! (and keep them charged!)
Another point... The lighter you and your bike are, the larger the fraction any additional weight represents. For me, clocking in at 6' 3" tall, 220 - 230 lbs (depending on time of year), and a bike with lamps, luggage rack, etc, weighing in at, oh, lets call it 35 lbs - no, make it 40 lbs, given clothes, shoes, helmet, etc - and it's around 270, so a 15 lb battery is only 5.5% or so - not a huge cost. If you're 4' 3", say, 75 lbs clothed, and you have an ultra-light bike and motor system at, oh, say, 20 lbs complete, you're at about 95 lbs and so a 15 lb battery would be around 15.8%, three times as much of a big deal. What I'm saying is, your comment about weight being carried around being a problem was also an overly-broad statement!
Personally, I don't even notice the weight when I'm hauling groceries home in my bike's baskets, nor do I notice the trailer when I'm using it! And the reason I don't notice is because I've got good gearing and electrification with plenty of power - which gets back to my point about "you can't have too much power (in the TSDZ2 world)." 8)