Another reason is because it’s easier to close/change bus routes as opposed to doing the same on roads, so it’s a bigger job for Google to keep on top of. They struggle enough with roads, so closed bridges, paths, and parks can be a total nightmare - especially when councils or towns “forget” to update.

Mostly it’s just CYA for google since cycling is more dangerous than driving (due to the people driving), so there’s more surface area for them to get sued.

But yeah

• turns and crossings that look safe on a map don’t have very much data on whether they’re actually safe, because google has a thousand times as much information about drivers than cyclists.
• google sometimes suggests routes that can’t be traversed, legally or at all, by a bike. Same reason.
• sometimes google suggests avoiding something a bike doesn’t actually have to worry about. This is actually the category of error I see the most: google sends you around something when you could simply walk your bike through it, or ride through it, because you’re not a car.

I think it means try Organic Maps

Biking is also pretty dependent on the individual and their setup. The elevation changes, distances, sustained speed, and terrain one individual and their equipment can handle can vary drastically with another person. Not to mention someone’s tolerance for whatever the weather might be doing at the time while you’re completely exposed to the elements on a bike or walking.

It’s just them taking a “your results may vary” approach while covering their own ass.

Anecdotally, while driving in Colorado, I put in a destination that I was driving to in bike mode on accident. The destination was like 80 miles away from where I was and involved climbing and descending a mountain pass. Google Maps was very optimistic about how long it would take me to bike there…all without knowing my anything about my health, the kind of bike I have, if I would be able to bike at that elevation, etc. (being Google they probably knew)

I heard that part of the motivation behind games like Pokémon Go is that they can collect data on previously unrecorded pedestrian routes between major landmarks or points of interest.

So Google’s directions may be based on crowd sourced routes that have never been vetted as safe/legal for pedestrians and cyclists.

It’s just a legal safety net that they cannot know whether at the moment the route is cycling-safe. So while you can follow their route, real-world situations might differ and hence you need to think for yourself.

Over here they show the same warning for pedestrian and car routes. Which is sad, because it tells me that enough people blindly drive into shit based off of a routing app that they need to tell people to please not turn their 2 braincells off, as much as a difference that is going to make…

My guess is that it may not be factoring traffic conditions for bicycle directions

Uphill?

I do a lot of biking and for me Organic Maps has proven to be worthy of the navigation.

The route may not include possible bike (out even pedestrian) specific route options, such as curb cuts, parking lot connections, or other paths commonly used by bikes. It may also route you on roads that may not be bike safe.

Probably “this route may or may not be a construction zone and/or actually have any kind of bike lane”

I use Komoot for bike routes. Its not perfect, but it will give you much safer routes than google. It has a lot more info on elevation and road types too.

That means that Google does not have correct data on bike lanes.

It means that for legal purposes Google is going to assume you stop for red lights.