When it comes to putting — the area of my game which is the most troubled — I tend to run down some pretty nerdy rabbit holes. Maybe if I keep digging, I’ll learn about something I never knew before, and bingo! My putting woes will be a thing of the past, and my game will hit a new level.
I haven’t had much luck with that second part, but the first part works flawlessly. It proved so once again when I called up Guerin Rife, one of the smartest men inputting and, indeed, golf. He invented Rife’s innovative two-bar technology and is the mind behind EVNRoll’s line of putters. MOI is a driving force behind Guerin’s designs, so I asked him for an explanation about what it is, and how it can help golfers.
MOI measures how much the putter twists on off-center hits
MOI stands for Moment of Inertia. Every putter has it, and you measure it using an MOI machine. A putter with high MOI won’t twist as much as a putter with low MOI.
“MOI is a measurement of a putter face’s resistance on off-center hits,” Rife says. “The higher the MOI, the more resistant the putter is to twisting.”
Different head designs increase and decrease MOI
When the ball is hit off the toe of the putter head, the weight of the ball means the blade will open slightly. When the ball is hit more towards the heel of the putter, the blade will close slightly. A higher MOI putter decreases the amount the putter twists. But how do putter designers actually increase MOI?
“MOI increases when you redistribute the weight to the sides of the putter head,” Rife says. “When you reinforce the toe and heel of the putter, the more resistance to twisting [on off-center hits].”
EVNRoll’s ER9 10k putter (the 10k stands for 10,000 MOI) has since been discontinued but is still popular in Germany — “The Germans love how stable that thing is,” Rife says — features a lighter-weight aluminum body, a hollowed-out center, and two steel rods to increase MOI. His newer Outback design features an aluminum body with a steel boomerang fastened to the underside of the putter for the same reason, Rife says.
An old-school blade putter, by contrast, has less heel-toe stability and therefore is prone to twisting. So if you use one, you better be sure you hit the sweet spot of the putter consistently. Read More
