unrecognized object error when reading simple factor vector

[ofajardo]

When reading the following file this error arises:

The file contains an unrecognized object

Trying to isolate the problem a bit, saving only the first column to a new RData file (seasons_bad.RData in the attachment) like this

> bike2 = bike[,1]
> save(bike2, file="season_bad.RData")

also raises the error.

However, if I save it like this (seasons_good.RData), then no error

> bike2 = bike[1:731,1]
> save(bike2, file="season_good.RData")

Using R 4.0.2 on a mac OS 11.6.4

thanks!

original report
seaons.zip