2000 Sturgis, SD to Marysville, WA on my 2000 Heritage Softail Classic. 17 hours and 1194 miles.

2006 Bakersfield, CA to Marysville, WA on my 2006 Gold Wing. 17 hours and 1076 miles.

Several 900 mile days on my 2002 Ultra Classic. No long days on my 2001 Road King Classic...as of yet.

 

I've done 1000 miles in 14 hours a couple of times when I was living in Park City Utah. Pleanty of concrete to run and smokey does not seem to bother with high speed cruising. If you try to make a fast run you should drink pleanty of water. I would alays fuel with the bike upright to get a little more distance between stops. GPS is a life saver in that you can see how far the next fuel stop is. It's really easy to do 1000 especially if you have a good seat (road Zep). I really prefer taking the side roads and enjoying the ride. If you're going after the Cert just make sure you keep your gas receipts! ...and by all means enjoy the ride!

 

I have done Buffalo NY to Myrtle Beach a few times always in under 24 hours , Its right around 1000 miles each way . I always stop whenever I feel like it {bad back} I use a Corbin seat with a sheepskin covered gel pad for long trips , it really helps. I also use a Kuryakyn tombstone bag between my back and the sissy bar , It holds a good amount of stuff that you can grab while riding 80mph.
I have never heard anyone else that has one of the bags but I recommend them for traveling.