Check your pressure gauge!

The offending gauge, middle, along with two accurate Accu-Gauges.

Tell me, have you ever checked the accuracy of a new tire pressure gauge before using it?

Neither have I. That is, until I got a lesson.

Recently I initiated a test to determine if, as some anecdotal reports suggest, a tire filled with CO2 loses pressure more quickly than one filled with air (more on that in a later post). CO2 tanks are sometimes seen as an alternative to compressors—while finite in capacity, they are very fast and completely portable.

I used the front tires of our 110 as test subjects. I deflated both completely, then filled one to 40 PSI using a CO2 tank and the hose/trigger/gauge assembly I keep with the tank. I filled the other to the same pressure with the built-in ARB compressor on the JATAC, using its own hose/trigger/gauge.

I decided it would be smart to verify exactly equal pressure in each tire using a separate gauge, so I checked the air-filled tire with one of our Accu-Gauges—40 PSI on the dot. Then the CO2-filled tire—49 PSI.

Uh . . . what? I checked it again. Same result. I checked the tire with another AccuGauge—49 PSI. I checked it with a $2.99 plastic-bodied pen gauge—49 PSI. I put the CO2 tank’s gauge back on it—40 PSI. I checked the other tire which I knew to be at 40 PSI, and the CO2 tank’s gauge read 32 PSI.

I’d always assumed that consumer-grade pressure gauges could be off by a pound or two—immaterial in most situations. But 25 percent? That represents a potentially dangerous discrepancy. If, for example, I filled the E-range tires on our F350 to their maximum recommended pressure of 80 PSI before hauling a heavy load, they would be nearly 20 PSI over that if I used the faulty gauge. (I’m reminded here of a passage in Fear and Loathing in Las Vegas involving a Cadillac El Dorado . . .)

Suffice to say I’ll never again use a new gauge without checking it against at least a couple others. 

No hitch mount needed . . .

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 . . . nor a roof rack. 

Folding bicycles are nothing new. Traditionally, however, you sacrifice something for the convenient portability intrinsic to the concept. Wheels are usually comically undersized, and the frame resembles something that might be ridden around a circus ring by a trained bear. And, of course, most of them are designed for street duty only.

Not so with the Montague Paratrooper. Its wheels are "normal" 26-inchers (in fact a 650B/27.5-inch model is available), and the frame, while eschewing the conventional triangle construction, is no more odd-looking than many rigid-framed models—in fact many people don't realize my Montague is a folder until I tell them, or they ask how I got it to camp in an FJ40 or a camper-equipped pickup with no external racks. 

The Montague folding bicycle line, in contrast to six years ago when I got this one, now comprises a dozen models, from a basic urban commuter to a flagship Shimano-XT-equipped mountain bike. The mountain bikes share the basic structure of a (visually) massive boxed aluminum-alloy beam where a normal bike's top tube would be. This comes close to duplicating the stiffness of a traditional triangulated main frame. A triangulated chain- and seat-stay structure wraps around the seat tube and connects to a modified quick-release skewer. When released, the frame pivots around the seat tube and folds nearly 180 degrees, essentially halving the bicycle's length with the front wheel removed.

In a soft transit case the Paratrooper fits easily behind the seats of our 2012 Tacoma Extracab—in fact, I have an idea that, by ordering the optional folding pedals, two Paratroopers would fit there. We hope to test this soon.

How does it ride? The highest compliment I can give the Paratrooper is that the folding nature of the bike is essentially invisible while pedaling it. I detected no odd handling characteristics or undue flex. It feels like any number of non-folding front-suspension mountain bikes. Of course, I'm a (these days) relatively light 150 pounds and a recreational cyclist—a 200-pound MTB racer might have a different impression.

The clever bit. Everything pivots around the seat tube.

Where the Paratrooper (and all Montague bikes) suffers somewhat is in component selection, especially when compared with non-folding bicycles in the same price range. It should be apparent that a large part of the cost of this bicycle goes into the complex frame, so one can hardly expect comparable components—and components, of course, are easy to upgrade if one or more does not perform as you expect. My biggest beef with my 2009 model is the front mechanical disc brake, which simply does not work very well (although I've never used a mechanical disc brake that I thought worked as well as a good cantilever brake, except perhaps in wet conditions). The rear derailleur is a competent SRAM X5, the front a Shimano Altus. The suspension fork and crank are SR Suntour. I do note that several bits seem to have been upgraded in the interim, and there's now a clever cargo rack.

Especially with a camper mounted, I was extremely loath to hang a hitch-mounted bike carrier off the back of the Tacoma. It adds weight where you least want it, reduces the departure angle, adds considerable hassle to accessing the camper, and coats the bike(s) with trail dust. Theft is a worry as well.

The Montague solves all those problems. Highly recommended.