I should have been writing a ride report today, with pictures of me, my bike, my friend and some great scenery....but instead I'm writing about another disappointing failure that made me scuttle the day's ride, after I drove 130 miles to get to the mountains.... I guess I'm not used to the ways of lithium batteries, but now I have been initiated. Sunday, I unloaded the 501 for a day of scenic adventures with my buddy KJ. We haven't seen each other since last autumn, and it was supposed to be a birthday celebration for me (a day early). After a bit of chatting and catching up, we suited up and prepared to warm up our bikes. I turned the key and listened to the fuel pump pressurizing, then hit the starter button. Three revolutions later, the engine came to a halt. And that was the end of my day. I was perplexed, because the bike had been starting flawlessy, including last weekend. I loaded my bike back up, took off my riding gear and prepared to go home. At home, the battery showed 9.3 measly volts...not even enough to wave bye bye with. I suspected that lithium batteries run at a certain level right up to the end and drop off to nothing all in one swell foop, where as lead acid batteries start to lose their performance at a much slower and even rate, giving a warning ahead of time that they will go bad. On my old 450, I could have swung out the old kickstarter and gotten the Kehein carburetor to deliver fuel to the engine. But I could only look at the 501, my heart sinking as silence prevailed. I ordered a new lithium battery, and a charger that was matched to its needs, plus a micro charger to carry on the trail with me, so that this would never happen again. Bu t I am also wondering if I should just go to a lead acid battery. All my old lead acid batteries seemed to last 3 to 5 years before conking out, while this lithium one (that came stock in the bike) only lasted about a year and half. Short lived and rather expensive compared to lead acid batteries. Anyway, I hope the new battery last longer than the original.