Thanks,
yes I have seen the graphs the give the huge difference in time vs amp drain. It looks like I can pull at least 1.5 c from the pack. I went ahead and ordered the first string. I'm going to build two strings before I deploy them. My first test will be on 36v 19ah. two string pack.
The truth is I'm doubtful that 9.5ah will be the real ah value, as I bought ebay chinese cells. But if it is two strings will be enough to power the bike, I think. If not I'll just add another string.
This is my dead of winter project, so we shall see how it goes maybe I can have it ready in the spring. I use a 2 way switch on my trike so I can put a sla battery on one leg and the nimh on the other, I can use one pack till it is to low to use further the switch to the other so that I can use both without mixing them.