You should have a "pan" control in just about any recording program or recorder.
What are you using?
As has been said, most sources such as guitar, vocals, bass, etc. are mono sources and should be recorded in mono and panned for effect. I record keyboards as two mono sources since when I record a stereo track, I can't pan either side, only the track.
But, you should not be turning your speakers up and down to achieve stereo balance, it should be done in your recording program or mixer or stand alone unit.
First thing would be to read how to use your equipment instead of asking how to work around something that is normally basic recording functions.
I use a Boss BR-900CD, and I've read the manual, and it does not go into this type of detail. I know it's basic, but I just started, hence I'm learning the basics. I have no problem recording; I'm just not knowledgeable of these recording terms that constantly get thrown around. Like I said, if there is a reliable guide that could explain some of that stuff, please point me to it. I don't really turn the speakers up and down. I just control the faders so that I can bring guitar out the left speaker and not the right (or vice versa). However, the only way I am able to do that is to bounce a track to a multi track. For example, I would need to bounce track 1 to track 1/2. That way I use both faders to control the sound from each speaker. Sorry, if this is confusing.