Unfortunately down south (Oztrailya that is) we speaketh in km's. My 2000 900ie has done 35,000kms and is still going strong. Despite numerous wheelies (admitted third gear at the most) and ride days at Eastern Creek.
My last first two 2-valver Dukes did 88,000kms and 77,000kms respectively. Just gotta keep maintaining them and they'll go forever. Probably?
Only 10K on the Monster, but 35K on the Twincam FXDX and 40K on my wife's Evo Superglide. No problems at all from any of them. Had 28K on her 1988 Sporty without any problems. I had 40K on my '91 Lowrider when I sold it and the only problem (other than a big crash) was an o ring in the push rod tube that failed at 35K. Took me an afternoon to fix. Had a 1983 Honda (head hung in shame :-[) CB1000C. At 55K, it developed a leak between the 2 transmissions (yep, a 10 speed with 2 shifters on the left side). It was still running fine when I sold it at 65K.
15K is nothing on modern bikes unless you flog them mercilessly.