How can I convert a .cue / .bin ( with cdr tracks) image into a single .iso file?

You should look at bchunk, which is specifically meant for this type of conversion. You should be able to install it with sudo yum install bchunk, but I'm only 95% sure it's in the standard repo. bchunk will create an ISO from any data tracks, and CDR for any CD audio. If you want everything in one ISO bchunk is not appropriate.

The syntax is like this,

bchunk IMAGE.bin IMAGE.cue IMAGE.iso

To create a single ISO with all the tracks in one take a look at bin2iso. bin2iso is most likely not included in your standard repo. Although RPMs do exist unofficially online. I would recommend using PowerISO over bin2iso, as bin2iso is fairly non-updated.

bin2iso <cuefile>

You also would be able to the conversion PowerISO. It is commercial software, but the linux version is freeware. Sometimes if I have problems with the Free Software for different image conversions, I give PowerISO a go.

If the BIN file contains CD-Audio tracks you cannot convert it to an ISO image! The reason for this is that, unlike e.g. a CD-ROM, the data structure of an audio CD is fundamentally incompatible with an ISO 9660 file system. See the link below for a paper that gives a good explanation of this:

http://journal.code4lib.org/articles/9581

However, you could use bchunk (as suggested above) with the -w option, which generates output in WAV format. Command line would be something like this:

bchunk -s -w IMAGE.bin IMAGE.cue IMAGE

This will create WAV files for each audio track, e.g.:

IMAGE001.wav
IMAGE002.wav

Etcetera. The -s switch does a byte swap on the audio samples. If you omit it, the Endianness of the WAVs will be wrong, and they will play as static noise (a least that's what happened when I last tried).