Huskey,
It's ok riding an execise bike in the bedroom while ******, even bollocky.
Yelling at your self in the mirror is quite ok. In any case the problem is only threre if your facing the mirror and get off to punch the ***** playing chicken with you.
Turn the exercise bike around 180 degrees and you can even look over your shoulder and yell; "Your f*cking lucky I didn't hit you you drunken b*stard!
Each to his/her own!
So far as police breathalising you for being drunk on a bicycle. It really depends on the law of the land that you do it in.
In NSW, Australia they can do it but the maximum fine that can be imposed for any bicycle offence is $70 AUD, that is about $53 US, 43 Euro or 26 Pound. Scarcely enough to stop the drunks getting home "safely".
Kind regards,