Get a list of all available go versions by running:
curl -s "https://golang.org/dl/?mode=json&include=all" | jq -r '.[].version' | sort -V
To install latest version of go (not including beta versions) by using existing go installation for bootstrapping:
GOLATEST=$(curl -s "https://golang.org/dl/?mode=json&include=all" | jq -r '.[].version | select(contains("beta") | not )' | sort -V | tail -1)
go get golang.org/dl/$GOLATEST # compiles go downloader
$GOLATEST download # downloads go release to ~/sdk/ and installs to $GOPATH/bin/
$GOLATEST version # check that it worked
Set the new version as default
ln -sf $GOPATH/bin/$GOLATEST $GOPATH/bin/go