the more stuff we have the more maintenance repairs failures we have to deal with. got a new light last Fall. 1st ride out it kept turning off while I was riding. it was my only light on at the time. couldn't figure out why. after a cpl times of that I started using it on a lower power setting. that seemed to do the trick. but then I tried the higher power setting & it worked better longer. thought it might over heating or the battery wasn't a good mate ... eventually no other rides it did not quit on high power w/ the same battery ... go figure. this year I've mated it w/ a smaller battery & have had no issues at full power ... go figure ...