The drizzle started lightly in late afternoon, as we hummed along gorgeous countryside south of Dargaville on New Zealand’s North Island.

Then the skies opened up and wreaked a mighty wrath of downpour that didn’t let up. We were drenched through our rain jackets even before we hit a long gravel road that quickly became a mud pit. All four wheels on our two tandem bicycles were rubbing and slurping with caked-on slop, and our parental resolve to stay positive eroded with each new hill and turn until we were muttering curse words to ourselves, both yearning for and dreading our arrival and inevitable tent-making in the teeming storm.

But our sons, Heron (8) and Sitka (6) didn’t notice the fouling of our mood – they were too busy recounting every detail they’d learned earlier in the day at the Dargaville Museum (the impromptu stop we made at Heron’s insistence). Each time we were forced to dismount and push in the sloppy sludge, they became Heron and Sitka Land-Gillovich, immigrant gumdiggers from Croatia in the early 20th century, seeking their fortune in the pooling muck. Being shown a sopping pile of sandstone goo every few minutes was sufficiently adorable to defuse our grump and keep us slogging on.

The boys’ merry karma served us well. We arrived after nightfall at the campground, resigned to erect our tent on a concrete slab under an awning, when a red truck pulled up. Ernie said his wife Sylvia had told him to go fetch the miserable-looking family she spotted from the window of their summer vacation home, and bring them in for a night’s reprieve in their spare bedrooms. It was a lovely evening with new friends, freshly picked avocados and hot Milo for the boys, who slept instantly and happily with dreams of Kauri gum dancing in their heads.

We’ve lost track of how many people tell us they stopped traveling after they had kids. Sure, we go a little slower than we did without our added passengers (not much, really, now that they’ve started pedalling, too). But we see much more, learn much more, and have way more fun –all four of us.

We started our “Cape to Bluff” (north tip to south tip) ride across New Zealand with 240 other cyclists, who coincidentally were launching their Tour Aotearoa at the same time as us. With only a mini-tent, bag of protein bars and credit card, they were aiming to finish in 10 to 25 days. We had three months.

So while our uber-fit new friends were sweating 200km a day, we were stopping to run obstacle courses on schoolyard play structures. Or improving our frisbee skills. Or playing shark-eat-fish in the campground swimming pool.

We encounter a lot of curiosity on our rest stops about how the boys are “getting on.” At first, we cringed when strangers asked, “So what do you fellas think of Mom and Dad lugging you around on those bikes?” But without fail they grin big and say, “We LOVE it!”

In fact, on the days we stop and rest our weary bike butts, the boys inevitably ask when we’ll start biking again. One time, they actually used their birthday money stash to rent a pair of kids’ bikes from the campground, so they wouldn’t go a day without cycling.

We’ve also had many inquiries about what we’re doing for the boys’ schooling. We say we’re “world-schooling” – the road is their classroom, and every day is a field trip. So far we’ve learned about glaciers, volcanoes and caves; sheep, kiwi birds and kangaroos; history, geography and politics (with a tour of New Zealand’s parliament). That’s in addition to the five hours a day of on-bike Q&A, on whatever topic piques the boys’ interest that day – from the digestive system and how milk is made, to evolution and the history of European explorers.

At a recent visit to a bike shop to get some repairs done, the boys stunned the owner by asking how much his mark-up was, leading to an educational discussion about margins and the economics of the bicycle business.

In the end, however, it’s seeing the world from a child’s eyes that brings the most benefits when cycling with your kids. In the middle of nasty steep climbs, our sons start cheering, “Go Daddy go!” Every stone wall is a balance beam, every tree root is a hurdle to jump over, every pile of driftwood is a fort, and every beach is an elaborate kingdom with castles and moats waiting to be built.

On one particularly rainy morning, we woke up to a drenched tent and wet rain jackets. Trying to be playful, Ed adapted the words to the Lego movie song, Everything is Awesome:

Midway through Daddy’s ranting rap about everything that was soaked, Sitka interrupted.

 “No Daddy, it’s…

Which he sang while running around in circles in his raincoat, revelling in the raindrops.

Just try being a grump after that.