I took the liberty to hit Cycle Trader used Birmingham Al as the starting point and 400 mile distance. Here are two that came up.
I'll need to ask the guy who I bought it from. He's been good at talking to me even after the sale.in the manual it said every 10 years or 100k miles, which ever happens first
so the real question is, when were the changed last???????
the wing engine is and interference engine, in other words, belts go, pistons and valves make contact, not pretty