RPMs are generated from the speed when the thumb releases the ball to where the fingers release the ball, and how far the fingers travel during the release. The further the fingers are on the inside of the ball, and below the equator at release, more RPMs can be generated. Looking at the following release position, they are ranked from weakest to strongest, left to right. Note how the fingers are in relation to the equator of the ball marked by the yellow line.

To view more releases and how RPMs vary, see our release video comparison page.

RPMs are best measured right after the release. This gives you the representation of how your physical game is affecting RPMs. As the bowling ball rolls down the lane, its RPMs will be influenced by the amount of friction imparted by the lane surface. The more friction, RPMs will increase.

Use a low flare bowling ball such as a plastic or polyester bowling ball. Place a contrasting piece of tape from the Postive Axis Point to above the fingers. Video tape your release from behind so that ball from your release to the arrows is clearly visible. Replay the recorded video back using frame by frame viewing from the point of release. Keep note of where the piece of tape points.

Tape position at release

Advance the video frame by frame for 10 frames and keep track how many times the bowling ball revolves.
Enter the number of revolutions ( example 1.3, 2.5 )
Your RPMs =

Advance the video frame by frame and count how many video frames occur between 1 revolution.

Select your camera fps 15 25 30 60 300

Enter the number of frames ( example 2.3, 3.5 )
Your RPMs =

Speed	RPMs
15 mph	200 rpm
16 mph	250 rpm
17 mph	300 rpm
18 mph	350 rpm
19 mph	400 rpm
20 mph	450 rpm