Mistaken mystique: myths of tire repair

Despite significant advances in technology and huge reductions in the frequency of failure (certain infamous Firestone models excepted), tires remain the number one cause of vehicle trouble, whether you’re driving your minivan to Disneyland or a Defender to Dodoma. 

The minivan can get by with a single spare tire. For an expedition vehicle you need to think a little more comprehensively. A second spare is a good start, but the very best strategy is to combine that with the means to accomplish your own tire repairs. Fortunately there are many products available to make the job easier, if not always effortless.

A surprising number of the Land Cruisers Roseann and I see and use in Tanzania and Kenya still ride on stout, tube-type, 10-ply-rated bias-ply tires mounted on split rims (or, more properly, retaining-ring or locking-ring rims). I even ran this type of rim (with BFG All-Terrains) on my FJ40 for several years while guiding in Mexico. Such rims can be disassembled with hand tools to remove the tire and tube, but I found I experienced more flats with tubes, and the process to repair a simple puncture involved the same complete disassembly of the rim as a major sidewall split. I got really good at it, but it was still a pain, and the romance of having clients marvel at the procedure soon wore off. 

Given todays’ availability of high-quality compressors, comprehensive tire-plug repair kits, and, for extensive sidewall repairs, various bead-breaking tools, there’s really no reason any more to use tubes or locking-rim wheels. Most simple punctures can be repaired with a plug while the wheel is still on the vehicle—I’ve repaired such holes before the tire had a chance to completely deflate. 

It’s easy to become proficient at plug repairs with just a practice session or two, and that skill will handle probably 90 percent of tire problems you’ll encounter. But when presented with a tire that has popped its bead off the rim, or a serious sidewall split that demands repair from inside the tire carcass, most of us still become gripped with angst. Doesn’t reseating a bead involve flammable liquids and YouTube-prone explosive effects, or at the very least an air compressor or tank capable of producing a really big volume of air? Hundreds of posts on dozens of forums will tell you so. Even a video I recently watched from someone who should know better reinforced the idea that you need a big compressor and/or air reservoir to successfully reseat the bead on a tire. 

The truth is, it just ain’t so. To prove it, I once reseated the bead on a 255/85 R16 tire using an Extreme Outback ExpeditionAire compressor, a clever product that employs a pair of toy-like AtomAire pumps each capable of no more than .9 cfm (cubic feet per minute) flow. Doing the same with any decent compressor is easy (although I won’t vouch for the $29.99 Costco variety).

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Speed vs. economy, or Fd = 1/2pv(squared) x CdA

Diesel engines such as this fine 1HZ are inherently economical, but they still have to work harder to push a vehicle faster Fuel economy is a funny subject. Very, very few people want to admit their vehicles get poor mileage. The overwhelming tendency is to fudge the other way when the subject comes up. I know for a fact there are guys who get 25 miles per gallon at 75 miles per hour in their one-ton diesel pickups while towing their 30-foot Airstream trailers, because I hear it with astonishing frequency. 

I also know they don’t. 

I never say as much when presented with these or similar absurd boasts, because there’s simply no profit in doing so. All I do is raise my eyebrows and say, subtly, “Wow. That would be impressive.” To show skepticism, much less outright derision, provokes the same peculiar outrage one receives doubting someone who claims to have been abducted and studied by aliens. There’s just no point in arguing. 

There’s also no point in arguing with the laws of physics—especially those relating to speed. Note that formula in the headline. In plain English it states that the drag (Fd) on a solid object moving through a fluid medium (which in physics includes air) is a function of one-half the density (p) of the medium times the speed (v) of the object, squared, times the drag coefficient (Cd) of the object times its cross sectional area (A). 

Note in particular the reference to the square of speed. That means that as speed goes up, the drag that results rises on a logarithmic curve. If speed doubles, drag quadruples. 

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Touring tip: When it's tool time on the road

Published with the permission of RoadRUNNER Motorcycle Touring & Travel Magazine for Overland Tech & Travel / Overland Expo only. Not for sale or distribution.If you’re like most adventure motorcyclists, you don’t want any type of mechanical problem to deal with during a motorcycle tour. And, of course, the best way to keep that from happening is a heavy dose of preventative medicine before your bike ever leaves the garage. But unforeseen mechanical malfunctions can and do happen out on the road. So, taking selected tools with you and knowing how to use them are sensible precautions for any touring rider.

Key Assumptions: If you ask 10 different riders for their list of necessary tools to have along, you may get 10 different lists. That’s probably because of the assumptions each person is making in several key areas:

•  Length of Trip: The longer you expect to be on the road the more likely it is that something on the bike will need repair. If your trip involves going around the globe, then many more tools and spare parts will be needed than for a weekend jaunt to the mountains.
• Type of Bike & Riding: All other things being equal, dual-sport riding and adventure touring are more likely to result in something coming loose or a bike going down than while street riding.
• Riding Environment: Riding in remote locations usually requires riders to be more self-reliant in fixing whatever needs repairing. 
• Number of Riders in the Group: The solitary rider must carry all of the tools and spare parts he or she might need. In group riding situations the load can be spread amongst the riders. 
• Mechanical Expertise of Rider(s): There’s no point in carrying a lot of tools and spare parts if you don’t know how to use them to make the repairs. Riders traveling long distances in remote areas, however, should have the requisite mechanical expertise and equipment to repair most any type of mechanical malfunction. 

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Is Gross Vehicle Weight Rating . . . Overrated?

We all know most of America is overweight these days. But 2,000 pounds overweight? 

Scott Lesak wrote us regarding his 1997 Mitsubishi Montero (the one in front here), which he has outfitted extensively for overland travel (his brother Mark owns the one following). Recently, Scott weighed virtually every piece of gear that goes into the Montero for a typical camping trip, and after adding in the curb weight of the vehicle, plus occupants, was concerned, if not really surprised, to find the total nearly 2,000 pounds higher than the factory’s listed 5,700-pound GVWR (Gross Vehicle Weight Rating includes empty vehicle weight plus all fluids, occupants, and cargo). He wondered if by carrying that much excess weight he was, a) risking damage to the vehicle, and, b) compromising safety on the road through reduced braking performance, etc. 

To which, of course, the short answer is yes and yes. 

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Why I hate Nalgene bottles

Few outdoor product manufacturers have attained the market dominance enjoyed by the Nalge Company, once an obscure maker of laboratory storage containers, after company president Marsh Hyman discovered his son’s Boy Scout troop was using their one-liter bottles as canteens early in the 1970s. The subsequent rebranding of Nalgene Outdoor Products was successful beyond the wildest dreams of marketing people who had previously relied on guys wearing lab coats and pocket protectors as customers. So successful, in fact, that I seriously doubt anyone reading this has not at some point had a drink of water from a Nalgene.

I drank the water, and the Kool-Aid, early on. The original one-liter white HDPE bottles with the wide cap were light, tough, and fit perfectly in the side pockets of my Camp Trails frame pack. They were easy to fill from a stream or bucket, and didn’t leak. You could chill the contents with ice cubes, or freeze the whole bottle with impunity. The Austrian Olicamp bottles I’d been using were leakproof and tough, too, but had a tiny opening and a fiddly two-piece top, so—despite years of yeoman service, including a backpacking trip spanning southern Arizona and three mountain ranges—I shelved them and shamelessly embraced their replacements.

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FI-PIG, Gorilla Tape, and WD-40: Essential fix-it stuff

I would like an expert opinion about assembling a selection of adhesives, chemicals, and other products most useful for overland vehicle field repair issues such as cracked hoses, radiators, or fuel lines, and for replacing gaskets, joining metal or plastic pieces, sealing electrical repairs, and so on.

Alexander in Florida

Alexander’s question brought to mind the old aphorism about the perfect two-piece tool kit: WD-40 (to fix the things that are supposed to move but won’t) and duct tape (to fix the things that aren’t supposed to move but do). Kidding aside, it’s an excellent question—a very large number of field repairs involve some sort of leak or breakage that requires a chemical or mechanical fix. I looked in my own kit, enlisted the help of two of our OT&T experts—Duncan Barbour and Graham Jackson—and also queried my nephew, Jake Beggy, a master Toyota mechanic and fabricator. Here’s what we came up with, first in the way of commercial products and then in “bodge” fixes when nothing else is available.

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Fit to be tied: Tie-down torture tests the metal of Expeditionware Transport Loops

I’m never sure which alarms me more: a vehicle loaded with completely unsecured cargo and equipment, or one loaded with cargo and equipment secured poorly. After all, the former implies simple ignorance on the part of the owner, and ignorance can be overcome with education. But the latter implies some rudimentary level of awareness—and then a complete failure to do the simple arithmetic that will tell you what will happen to the 30-pound Hi-Lift jack bungeed to your front brush guard should you be, say, rear-ended at a stoplight. No, I am not making this up, and yes, I checked. Two neatly wound bungee cords comprised the total attachment of that jack to that brush guard. I’ve seen another Hi-Lift bungeed to a very well-constructed internal roll cage (talk about Manichaean reasoning), and uncounted tool boxes, fridges, and Pelican cases all held down by what are, let’s be frank, glorified rubber bands.

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The Myth of Compression Braking

Recently a remark by an acquaintance triggered me to dredge up a bit of knowledge I came by ages ago, during a short stint driving a diesel tractor/trailer rig for J.C. Penney between Phoenix and Tucson. The fellow, a UK resident, had recently sold his mid-90s Land Rover Discovery V8 with a five-speed manual transmission, and purchased a similar Discovery equipped with a 200 Tdi turbodiesel engine, also with a five-speed. Besides instantly doubling his fuel economy and then some, he’d noticed something else and mentioned it in an email. “I might be daft,” he wrote, “but I swear the petrol engine had better compression braking. But I know that’s impossible. It only had 9:1 compression, and the Tdi is 19:1. Something else must be at work.” 

I wrote him back a short reply: “That’s because diesel engines have no compression braking.” Which caused him to respond, “Now I think you’re daft.” 

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Do I really need a winch?

Recently my friend Sergio Mendez Santiago emailed me from Puerto Vallarta, Mexico, where he and his wife, Ruth, are putting the finishing touches on their new Mitsubishi Triton, a fine turbodiesel-powered 4WD pickup (sadly unavailable in the U.S.). Like so many of us setting up a new vehicle, Sergio has been vacillating on the decision of whether or not to install a winch. We both thought it would be a good subject to explore. Since I have a Warn 8274 on my FJ40, and I installed a Warn M8000 on Roseann’s FJ60, I certainly appreciate their value (and I think my objectivity is on solid ground)—however, I certainly don’t think one absolutely needs a winch to be able to undertake even ambitious journeys.

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Do I really need a winch?

Recently my friend Sergio Mendez Santiago emailed me from Puerto Vallarta, Mexico, where he and his wife, Ruth, are putting the finishing touches on their new Mitsubishi Triton, a fine turbodiesel-powered 4WD pickup (sadly unavailable in the U.S.). Like so many of us setting up a new vehicle, Sergio has been vacillating on the decision of whether or not to install a winch. We both thought it would be a good subject to explore. Since I have a Warn 8274 on my FJ40, and I installed a Warn M8000 on Roseann’s FJ60, I certainly appreciate their value (and I think my objectivity is on solid ground)—however, I certainly don’t think one absolutely needs a winch to be able to undertake even ambitious journeys.

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