I think the rp15y is the year the 26A i dont know. But the last 6 is and the rp15y is what I asume is the proper range. I should hear back from my dealer today if not i will go down there before work.
Here's a nice VIN tool that will tell you what each digit means.
Link
In your case it breaks down to: (Each VIN is 17 digits)
1-Region: Asiacool thanks
1-2-Country: Japan
2-3-Manufacturer: Yamaha
4-8-Model Specific: RP15Y
9-Check Digit: Valid
10-Year: 2006
11-Assembly Plant: A
12-17-Serial Number: 000152