I passed my bike bug to my wife.

She has a nice specialized Vita bike (really nice hybrid) and wants to try biking the LA River from downtown to Long Beach then over to Newport Beach, stay at hotel for a night (or two if Labor Day) and bike back. It seems about 50 miles each way- which she can do. But she can't (won't try) to stand up and so has problems doing an emergency sprint or climb.
I'm a little nervous about it. Any thoughts?
Also a nice bike friendly hotel in Newport Beach? I never tried bringing my bike into a hotel before...
Any advice on how to get her to try standing???