I did 6 weeks on a 1983 CB900F long ago. Great bike. Worked fine.
I even did some gravel roads (with great care and concern)
Learn your fuel consumption against the wind and be careful to get fuel when you can. Out West it can be a long way between fuel stops so if you're concerned SLOW DOWN to best range speed.
CB750 is a great bike.
Ensure it's in tip top shape, don't try doing dirt bike roads and go have fun.