It was a bit premature, but I rode my age yesterday and then some.

The final tally was 44.6 miles, or 71.8 kilometers; I only needed 43.5 miles to make 70km, but I figure the additional mile and change constituted a punishment tax for being a wuss and riding my age in kilometers instead of miles.

My 70th birthday isn’t until Wednesday, but the forecast was not promising and yesterday’s weather looked (and was) superb, so I took a cue from Janis Joplin and got it while I could.

I’ve been in something of a rut lately, literally as well as figuratively. The drill has been to break out a cyclocross bike and ride a mix of roads and trails, the latter slashed into tire-grabbing ribbons by fatheads who shred (or stir) the gnar-gnar after a wet spell. The ruts they leave behind don’t pose a problem for anyone piloting a double-squishy with plenty of travel and 3-inch tires, but can be a tad jarring on a rigid drop-bar bike with 33mm rubber.

Still, it beats working, especially if I pick a day and hour when the usual suspects are likely to be hoeing a row in the cube farm. I managed 24 miles of that sort of thing on Thursday. But doubling up on that, on a Friday, sounded like a punishment tour, not a birthday celebration. Also, too much of the same-ol’, same-ol’.

What to do; what to do. …

Temps looked to be headed for the 60s, with wind from the west. Coasting down to the bosque would force me to commit to some proper distance while giving me plenty of options in case advancing age or some other wrinkled catastrophe reared its ill-considered comb-over in midride. Off I went.

It’s mostly off-street bike path (Arroyo del Oso) and downhill from the intersection of Tramway and Manitoba to the bike-ped bridge over I-25, barring a short, unpleasant stretch of Osuna between the western end of the Arroyo del Oso golf course and Brentwood.

But once I’m on the bridge it’s all bike path, all the time, depending upon how I choose to head home.

I’m prone to overdo and bad at math, so after following the North Diversion Channel Trail and the Paseo del Norte Trail to the Paseo del Bosque, I refused to be lulled into complacency by the early greenery, stifled various miles-enhancing impulses — Hang a right at I-40 and climb to 98th? Hang a left at Mountain and cruise past Old Town back to the NDCT? Continue south to Rio Bravo? — and pulled a U at Mountain, heading back to the NDCT the way I’d come.

The wind was mostly with me, so it felt like the right call, not least because it was all uphill back to El Rancho Pendejo. The question was: Which way back?

Arroyo del Oso is kind of a slog if ridden up from NDCT, with lots of stop and go plus a couple-three evil multiple-lane, median-divided, high-speed baby-highway crossings to negotiate with pale, failing, nearly-70-year-old legs. And my limited math skills seemed to indicate the mileage — kilometerage? — wouldn’t make the nut.

So I hung a left where the Paseo trail met the NDCT and headed northeast through Balloon Fiesta Park, where a few didoes through an underused office/light industrial ghetto connect to the Pan American Freeway, which in turn leads to the climb up Tramway — if you don’t mind riding a short stretch of shoulder alongside Pan American against high-speed, one-way traffic, which I kind of do. There’s been talk for years about extending the NDCT north to Roy, which would spare cyclists this game of chicken, but no action as of yet.

A quick digression: As I was rolling through the balloon park en route to doing battle with Pan American I saw a dude on what looked to be a gravel bike who’d left the official trail to drop down into La Cueva channel, a drainage like NDCT only without a bike path along the edge.

It made me wonder if, rather than risking the short against-traffic dash to Tramway from Balloon Fiesta Parkway, a savvy cyclist might be able to ride La Cueva channel underneath Pan American and I-25 all the way to Louisiana, then climb out somehow and head north to Elena, a less harrowing alternative to the 50-mph traffic of Tramway. Never saw the other dude again, so, maybe? To be continued. …

I took my chances on the Pan American shoulder, cautiously skirting two parked vehicles that may have had some unfortunate interaction — one car, one 18-wheeler — and started the half-hour ascent of Tramway to The County Line Bar-B-Q.

This is where the age thing manifested itself. A couple skinny young pups on them plastic-fantastic whirligigs with the disco brakes and what have you passed me so fast I had to stop to check my pulse, see if I still had one.

Nevertheless, I persisted, and upon hitting the stop sign at the barbecue joint it was clear that if I headed straight home I was going to wind up a couple klicks short of the full megillah. Thus I had to add a couple curlicues, flourishes, and do-si-dos to my little dance party before I could leave the floor and collapse into a medium-heavy lunch.

The official high was 69°, four degrees above normal. If that’s my birthday present, I’ll take it.

• Postscript: Lest anyone consider this even marginally impressive, my man the M-Dogg out in California reports having covered 9,000 feet of vertical and 166 miles in four days, none of which was his birthday.