how steep is the grade of the Golden Gate Bridge

[TCS]

The pedestrian/cycling decks on either side make two ungenerous 90º turns getting around the towers.

But that gives you a moment to appreciate the towers' magnificence.

Perhaps a nice detail to include if, hypothetically, one were writing a novel where the protagonist was riding across the bridge.  Pause at the first to consider life up to this point; pause at the second to consider life to come.   

[hikerjer]

"8,000 BIKES PER DAY in 2015 and it has only increased. Read the full report for data by hour, by month, and by day. Important if you are planning to cross, I think." -------  Like I said, it's a freaking circus.

[Inge]

I did not enjoy my crossing of the bridge with a fully loaded touring bike - not on the w side since you are not allowed to stop on that side. A all those pedestrians - not looking where they are going - moving left tot right and back again + walking on the bike path made a pain pain in the ..... For me if I ever have tocross the bridge again it will be on the w side. For on the pedestrian side you can not stop anyway due to the amount of pedestrian tourists and cycle tourists who do not know how to ride a bike.

[Rixtoy]

"8,000 BIKES PER DAY in 2015 and it has only increased. Read the full report for data by hour, by month, and by day. Important if you are planning to cross, I think." -------  Like I said, it's a freaking circus.

With an average speed of 17 mph for all riders recorded on one day in 2019 . . . how is that even possible with that many bikes of mixed abilities? . . .

The commuter bikers early in the morning show 17 mph as the 85th percentile, meaning they are going possibly 10 mph more than that.

I need to look at some of the videos of crossings.

Methinks the OP, who was looking for a melancholy or serendipitous moment for the protagonist should consider this crossing more like riding a roller coaster with his hair on fire.  Eeek!

[Rixtoy]

So, here is a recent video from a family riding across the bridge.
https://www.youtube.com/watch?v=TIrbRj7149Q

I thought they did a pretty good job managing the traffic and the MANY bridge maintenance barricades.

I can see now where the commuter/expert riders drive up the average speed.
I am guessing by the shadow angles this was ridden fairly early in the morning,

But, there are many places where the barriers are up and with two way traffic it is hard to imagine a bike with double panniers getting through those tight areas while still riding.

I think I will pick my time to cross based on the average hourly/daily volume data.

[driftlessregion]

Grade depends of which direction of course. Here it is
https://ridewithgps.com/routes/35279327