[MENTION=488697]bspierre[/MENTION]:
I have noticed a similar behavior. My ride to work is all uphill. If I forget to charge the battery, and try to go up the hill again at 7, 8 , or 9, the system will shut down. If I set it to 6 or lower, it will continue to run. When it was new, I could go up at any setting two or three times with no problem. I suspect that as the batteries get older, they lose their ability to deliver maximum power in addition to losing some distance-type capacity.