Just put a lid on it!

On what? On your head.

“Just put a lid on your head.” Tell it to your kids. Share it with your family members and yell it to the kids down the street.

Do this, and we’ll all be a lot better off.

Mid-last year, a good friend down the street decided to get more exercise. He’s a good dresser and generally looks a bit like a James Bond secret agent type.

He bought a very cool retro Schwinn bike with cool grey paint and yellow-rimmed wheels. And he showed up at the Starbucks one morning, very proud of himself for getting out there on a brisk morning and working up some sweat.

“Where’s your helmet?” I rudely inquired.

“I’m not wearing any helmet!” came the fashion-conscious reply. (Unlike the rest of us old-timers in the group, my friend still has a full head of flowing, gray hair.)

“Get a color-coordinated helmet — your wife and buddies want to see you around here next year!” I insisted.

My buddy shrugged it off. That’s the response of a lot of adults about bicycle safety. California requires kids to wear helmets, but too many adults still think helmets “are just for kids.”

They don’t know that 60 percent of all bike injuries are to adults, and most bike deaths are adults riding without helmets.

A short two months after my James Bond friend started riding without a helmet, Carrie and I were riding our own bikes down our hill to the Starbucks. Carrie’s a good rider and always wears a helmet. She’d never had a previous fall.

But on this morning something went wrong and she suddenly, without warning, went head over heals, chin- and face-first into the asphalt pavement right in front of my Schwinn-riding friend’s house.

I turned back to see my wife crumpled, motionless, on the asphalt. What appeared at first to be just a little slip had completely bloodied up my lovely wife with gashes and broken teeth.

Carrie was nearing shock as I helped her to my friend’s door. I rang the bell, and at 7 a.m. that morning my friend opened his door with a complete look of disbelief at seeing Carrie, covered with blood, sobbing.

Together, we attended to Carrie and discovered deep gashes in her chin and lip, along with abrasions on her hands and face. We cleaned her up and I ran her to the doctor’s office, where she received a dozen stitches, bandages, and then off to the dentist for four caps on her broken teeth.

Since then she’s been receiving treatments — a long, painful, expensive road from a simple, unexpected fall.

Carrie was wearing a helmet that day, but when she face-planted she still took severe facial injuries. But thank goodness she had a helmet — her head itself was protected from a direct hit — or else who knows what additional suffering a severe concussion may have caused? Injuries aside, Carrie’s helmet may have saved her life.

Three months after that accident my Schwinn-riding friend received terrible bicycle news again. His friend’s son was riding his bike at high speeds without a helmet when he hit the side of a large SUV. He suffered a direct head impact and was taken by ambulance to Henry Mayo Newhall Memorial Hospital with the expectation that his wounds would prove fatal.

After removing part of his skull and performing heroic acts, the doctors saved the boy who is now expected to recover. He has already been a full month in hospitals and his care will take many more months.

It should be noted that the boy’s dad has always insisted on proper safety gear, but this time the boy rode off unprotected. This, unfortunately, is too common.

After that near miss, my Schwinn-riding buddy rode his bike with new matching helmet to the coffee shop with a sheepish, but sincere, comment. “I guess I’ll be wearing a helmet from now on.”

And all his friends and family are so glad he is, because he’s a great guy and we want to see him around for a long, long time. Who care’s if “helmets aren’t cool.” Life is cooler.

As I returned home that morning I passed two little kids, perhaps ages 7 and 9, riding their Razor scooters off to school. Both had their helmets attached to their backpacks, not on their heads. I should have stopped them then and there and made them put them on.

Last year there were about 500,000 bike accidents in the U.S., of which 250,000 were head injuries. There were 800 head-injury deaths, of which 92 percent did not have helmets.

Most of the serious 250,000 non-fatal incidents were head injuries without helmet protection. Beyond lives lost and untold suffering, non-helmet bike injuries cost society $2.3 billion annually.

Yesterday I passed a teenager on a bike parked at the light. This boy was wearing a full Motocross-style helmet, complete with chin guard. My first thought was “dork!” But the second thought, right after the standard reflex, was “smart kid!”

Good for that smart kid and good for his parents! You be smart, too. Just “put a lid on it.” And make your kids and friends put a lid on it, too.

Gary Horton is a Valencia resident. “Full Speed to Port!” appears Wednesdays in The Signal.