Hm, if you can't start it on the stand, considering your weight advantage (over me), I guess that says something. I guess I'll know the story once I have it running; if it won't do 35 with me on it, then safe to say it's down on power.
Does your manual state the compression ratio of the motor?
But like I mentioned, I think this bike was sitting for almost 20 years, so I'd never expect the engine to be developing its maximum compression at this stage. Even if it's unworn, there's bound to be some losses due to lack of oil in the cylinder, light haze of corrosion on the piston rings/cylinder wall etc.
Guess I'll just have to test it once I have it running a while, and it's good and hot.