1. At what point should this belt be checked or replaced?

http://www.google.com/search?hl=en&q=+site:www.tradebit.com+kymco+manuals , the belt on the X-500 needs to be checked, not replaced every 12,000 miles. This is also listed in the owner’s manual. Most other manufactures state that belts should be replaced at a specific interval, usually around 12,000 miles or so. The Yamaha Majesty even has a light in the dash that comes on at 12,000 miles telling you to have the belt replaced. Why Kymco only requires a inspection instead of a replacement I don’t know.

2. What are the possible problems that could occur?

As far as replacing the belt it doesn’t look like too difficult a job. My X-500 only has 2300 miles on it right now. At the recommended 12,000 miles I’ll pull the drive belt cover off and measure the belt the way it shows in the manual. If it is out of specs I will replace it.

3. What are the symptoms of a belt going bad?

I would guess that when the belt is worn it will begin to slip and the RPMs at a given speed will start to rise higher than it would normally be at that same speed. Or maybe the belt just snaps and leaves you stranded in the middle of nowhere. If you only use your scooter around town you could probably ride it until the belt breaks. Then call a friend with a pickup to come rescue you. But if you use your scooter for long distance rides I would just replace it every 12,000 miles or so just to be safe.

4. What are some places/internet-sites that a belt could be purchased other than a Kymco Dealer?

I have seen after market belts listed for the X-500 here, http://www.scootertrap.com/Xciting500.htm
but as you can see they are $170.00. I’m going to guess that the OEM Kymco belt is much
cheaper and probably just as durable.

5. Is it better to get another brand of belt rather than a Kymco and if so why?

I’m going to give you my 2 cents worth about Kymco parts. Kymco builds a very nice product and the parts they use, almost all of which they make themselves, a rare thing nowadays, are first rate. Meaning they are on par with what you would get from one of the big Japanese motorcycle companies, only much less expensive. Kymco parts are not poorly manufactured Chinese crap. And even though Taiwan is just off the coast of China, companies in Taiwan build parts nothing like those in China. Many years ago I would buy machine tools from Taiwan and the tools where and I’m sure still are first rate, unlike those made in China. Before I would go looking at aftermarket parts, even those made in the good old US of A, that claim to be superior
in some way to the OEM Kymco parts I would want to see some type of proof and not just an opinion of them being better before I would pay a premium price for them. In other words I would stick with OEM parts which will in the case of Kymco, probably be less expensive
and just as good.