I posted here last year and received good advice, so I am back again with a different bike. I have a 2006 WR 450F that has been to two different shops now and my problem still persists. Bascially, I start with a charged battery, ride for a few hours and the bike will not start with starter. If I continue to ride until the battery is totally dead, the bike cannot be kicked started either. Here is what I know. I replaced the battery. Problem persisted. I took it to a shop, they recharged the battery, and checked the voltages. Seem to be in spec. Shop said, I may have a battery issue. I returned the battery, and replaced it with a Lithium battery. Problem persisted. New shop, that one had its chance. This shop is the dealer I purchased the bike from. The performed a diagnostic on it, and assured me that the voltage regulator was the problem. They believed it was an intermittent problem. I took the bike for a ride yesterday, and it could not start after 2 hours of riding. (about 50 miles) I suppose the stator may be the problem, but I suspect that I do not have a charging problem, but a discharging problem. Something eating amps while I ride. For the most part, electricity sucks, I hate it. I would rather have my toe nails pulled one by one then spend time doing this. but at $200 everytime I take the bike in, I can replace parts until things work just as easy as the so called experts. So what should I start with first. Guess I should start with least expensive to most expensive.