Biased roulette wheels are basically a thing of the past. Now they are hooked up to electric monitoring system (that also do the fun LCD displays above them),

Biased roulette wheels are basically a thing of the past. Now they are hooked up to electric monitoring system (that also do the fun LCD displays above them), monitor balance and track every winning number. If the computers notices a significant irregularity, they swap it out due to an abundance of caution, re-balance it and replace all the frets. The "unbalanced wheel" thing never really worked very well -- as it couldn't easily remove the houses MASSIVE 5%+ edge (00). Now, back in the day damage frets(frets divide the numbers) could be a rather astounding in cheap backwater casinos with worn wooden frets. If you noticed them, you could bet the opposite side (ball, even slowly was likely to coast over smooth worn frets) and you could crush the casino. Today, the combination of electronically monitored balance, irregularity tracking and strong metal frets make this more of a historical thing -- but had to be fun back in the day.