Hello,
I have a race friday it’s not an A race as I am not in super shape. Can I do a 5a6 hour ride today and still perform decent in a 1h 30m race.
The reason it’s beautiful weather and I have a day off.
Tomorrow I take complete rest Thursday easy spin. And Friday evening race.
Jens
If you want to prioritize the event on Friday, I’d highly recommend keeping your rides under two hours this week.
Shorter is better when an event is coming up. Those long rides, even if the effort is easy, tend to drain your energy, leaving you fatigued for your event.
Our tapers typically consist of 30-45 minute workouts the week of an A race. Since this one isn’t a huge priority for you, you could certainly ride longer than that, but 5-6 hours is probably a bit much. 
Good luck!