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Biased Roulette Wheels

Reviewed by the CasinoOnlineReviews deskUpdated Written for readers in the United States

Biased roulette wheels are wheels that give unexpected results and least probable by chance. This becomes ironic given the fact that roulette is a game based purely on luck. There are countless causes of a biased wheel.

In the early 20th century, rigging wheels and roulette tables was a common practice by casinos. However, that’s become less common. Today, most players speak of unintentional wheel bias which occurs with even the slightest discrepancies.

Wheel defects cannot be spotted with a naked eye. Gamblers who want to bank on this imperfection would need to record various results and study the data to spot a bias. This is what they call “clocking the wheel”. You must really want to win because this can be a tedious process.

Different Types of Wheel Bias

There are three main kinds of wheel bias in roulette – pocket bias, section bias and dynamic bias. With a pocket bias, the ball is more inclined to land in certain pockets due to lose pocket dividers as mentioned previously. Section bias occurs when the ball seemingly favours a specific area on the wheel while a dynamic bias gets detected by computer software.

Here are a few possible explanations for biased roulette wheels.

  1. The online casino has rigged the roulette wheel which means the results are to an extent controlled by the casino and is therefore not random.
  2. The roulette wheel may be faulty which could result in biased wheel play.
  3. Lose pocket dividers
  4. An unbalanced roulette table or wheel
  5. A deformed ball

Identifying a Biased Roulette Wheel

There are many ways of detecting whether a roulette wheel is biased or not. The most obvious being collecting and recording the data from a series of spins, and using that research to confirm whether a wheel is biased or not. But you can narrow the research process by focusing on the wheels that are most likely to be biased. Here are a few guidelines you can follow when trying to spot biased roulette wheels.

Tilted Wheels

Look out for roulette wheels that seem tilted. The greater the tilt, the more likely it is to present a bias. A tilted wheel itself doesn’t necessarily mean that its biased. But, when the tilt affects how the ball behaves like increased/decreased deceleration, then there’s an obvious bias. To figure out exactly where the wheel is most tilted, record on a sheet where the ball began to lose momentum or started to roll differently. Record even the slightest difference to spot where the tilt is.

Aged Wheels

The older style roulette wheels are more likely to be biased than modern wheels.

Roulette Ball Deformities

Spotting irregularities in roulette ball behaviour can also be an indication of a biased roulette wheel. Deformed balls can cause a bias and you can hear them rattle at different parts of the roulette wheel. If after a few spins you realize that the ball still rattles at the same spots then the ball is likely to be deformed. A deformed ball track is another possible indication of a biased roulette wheel as it leads to common drop points. When the ball only rattles at certain parts of the ball track, that could mean that the track is flawed in that area. By listening to the sound and where it occurs, you can identify deformed ball tracks as well as common drop points.

How Casinos Protect Themselves from Biased Wheels

Any casino would want to prevent bias players from exploiting the wheel because this could potentially result in great financial loss. We’ve summarized three preventative techniques below:

Equipment Checks

These include regular equipment inspections to ensure that everything is working properly. The process involves checking all the parts of the roulette wheel and table that affects play.

Recording Results

As much as players track results to find a bias, casinos do the same thing. Land based casinos keep electronic boards by the roulette table which they use to capture all the results to spot a bias, and to display some of the more recent results for gamblers who use trend betting.

Starbust Wheels

Starbust wheels use metal pocket dividers instead of wooden ones. These are less likely to become loose and create a biased wheel. Once again, this is a technique used by land-based casinos.

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