I found these two that use a car with the motorcycle. I'm not sure if you can do it with the motorbike itself, but there's a similar glitch in WD2.
You can also go out of bounds in some places by using explosions:
I already reload autosaves on that mission where you restore power to the bunker.
There are out of bounds spots in the game, but I don't think they save any time. You can use motorcycles to clip through walls.
I'm not really sure how long 100% would take. Any% can be done around 3 hours 20 minutes., so that leaves the rest. Online hacking would be very random, and I don't know why you would want do that. There was talk of "offline 100%" being a more viable category. I would put it at over 10 hours, but I need to see a route to estimate more clearly.
I've already tried to optimize the route mostly by myself. You can try to look at the route yourself.
I think the WR can go down to a high 3:21. What the current route doesn't have are the optimal times to jump out of the car/bike to skip dialogue. The speed of the vehicle and the type of vehicle (car/bike) heavily influences how Aiden falls to the ground. Dialogue can also be skipped when Aiden falls to the ground via explosives; there are a few parts where I could do more of that. Some of the driving routes also need to be looked at.
Not sure if there can be any new skips. The game is restricted by the objective/checkpoint system, so you can't move on without completing the current objective. Maybe you can try playing around with lures on the enemy AI during A2M10(Breadcrumbs) or something. Out of bounds also seems to be too slow for it to matter.
There are also a few other things like getting early scans in A4M2 (In Plain Sight) by shooting people early. But it seemed to be bugged for full game runs when Ouga tried it.