Just as an FYI. I have recently replaced the stator in my XC250, and am in the process of replacing it on the XC500i.
The stators on these bikes are sprayed in engine oil during operation. When I installed the new stator in the XC250 (which cured it of its charging problems, I am happy to pass on), I noticed (where the bolt heads contacted the stator) that the new stator definitely has some sort of conformal coating on it. I saw no evidence of conformal coating on the old stator.
So it seems that Kymco already has the problem sorted out, and added a conformal coating to the stator coils to prevent breakdown of the insulation.
This, unfortunately, means that pretty much every Kymco 250cc engine, as well as the Xciting 500, manufactured at least up until 2009, *WILL* eventually require the stator to be replaced, unless you get lucky and only use whatever motor oil doesn't end up damaging the stator insulation (something which we have NO information on). I started having the problems with the bikes after changing the oil (on the 250) and topping off oil (on the 500) with something I had bought at the local Autozone.
This also means that buying a stator on Ebay instead of from your dealer (and waiting for the slow boat from Taiwan to deliver it) is a complete crapshoot, since we don't know when Kymco started producing stators for each engine which have the fix.
Note that I was getting stranded on my XC500 prior to ordering the replacement stator; whenever I turned off the bike, I wouldn't know if it would actually crank over and start! I actually kept a 2nd fully charged battery under the seat and was hooking it up to the battery tender connecter for jumpstarting in these situations for a few weeks; near the end, simply driving the bike for two hours was sufficient to drain the primary battery (which is new, and being put on a tender each night) to the point where the low battery light was turning on at the end of my trip, which convinced me to stop putting off the repair.
I'll try to post a followup after the repair is done to see if this fixes the "getting stranded" issue; I don't have a lot of time to work on the bike each weekend, and I need to replace the stator, the clutch shoes, and perform a valve adjustment, so it might be a few weeks. I've had a couple of instances where it simply did not want to turn the engine over (as if it was dead-ending) and I suspected decompression problems, but each time a boost DOES cause the engine to turn over and fire up.
