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It turned out to be a bit of a flat morning

April 7, 2015
todays-flat

Left to right: a glueless patch, a tube going back in the tire (valve stem first), a cinder block to hold everything up and a full-size hand pump.

I started my morning by waking up out of a good sleep (like most people, I hope). As I happened to be sleeping in a parkade my alarm clock took the form of parking cars; first a black hatchback, closely followed by a fat white SUV.

I was wide awake and I was refreshed. The sun was shining, the birds were singing and I was starting this beautiful day with a full load of returnable beverage containers on my bicycle trailer.

It took me all of 10 minutes to get up and on my way but within a half hour a sudden flat tire on my bicycle trailer was already getting me down.

One way or the other, flat tires happen

First off, I should say that this is the second flat I’ve had in the cheap 20-inch Kenda gumwall tires I put on the bike trailer at the beginning of February. Secondly this flat was down to my having to ride though a glittering patch of broken glass in waste grass and weeds off the side of a paved alley in order to avoid being scissored by two opposing SUVs.

It’s sensible good manners in Vancouver back alleys (which are never really two lanes wide) for one vehicle to pull over and allow the other to comfortably pass. However, neither of these drivers were willing to stop.

That they didn’t hit dumpsters or something else or each other was more an issue of luck than skill I would say. By default I put as little faith in SUV drivers having a feel for their footprint on the road as some drivers put in the road sense of us cyclists.

Within two blocks, my right trailer tire was pancake flat — and under a very heavily-loaded trailer. I had to stop immediately and deal with the flat or — I worried — the steel wheel rim would cut into the Kenda tire’s soft gumwall sides.

It pays to periodically check your bicycle repair kit

People always say things like: “That fershugaling thing picked the worst possible time to break!” But the ratcheting socket wrench I carry just to detach and attach my bike trailer wheels must have failed some time in the last two months (since my last flat) when I had no need of it and giving me lots of time to find a replacement had I only checked it, say, once a month.

As it was, the socket wrench would only lock in a clockwise direction — good for tightening bolts but not for loosening them.

But I wasn’t replacing the tube, only patching it and there was no reason I couldn’t do that with the tire on the trailer.

The first thing I needed was a spot where I could fix the flat without being in anyone’s way — I chose a parking lot behind a business that didn’t open before 10 p.m.

Next I had to find something strong to prop up the right side of the trailer so that the wheel turned freely. There were piles of square cinder wall blocks of the right height just next door to where I had parked my bike and trailer.

Once the trailer was propped up on a cinder block I used a plastic tire lever to release the outside tire bead from the wheel rim.

I lost my trio of favourite Pedro’s tire levers last year when a collection of tools was stolen off my trailer and I haven’t gotten around to buying new ones because I have other levers that are just good enough.

With the tire off the outside of the rim I extracted the inner tube by pushing the valve stem straight up through the stem hole in the wheel rim and then carefully tugging both the tube and the stem together out from under the tire bead.

I’m careful not to pull out the tube by just pulling on the stem because tubes are utterly ruined if their valve stem is broken.

All I could do next was pump the tube full of air and hope that finding the puncture was as easy as listening and feeling for rushing air. Fortunately the puncture was hissingly obvious.

If I had wet down the tube with water before pumping it up I could’ve possibly found a smaller, silent leak by watching for telltale water bubbles but I didn’t have any water.

Because I’m pulling a trailer behind my bike, I can carry a full-size tire pump. This is a nice luxury. Not only can I fully inflate a 26-inch tire in a mere 40 pump strokes but I can quickly and easily help other cyclists if they need a pump. Because I have to pump up any stranger’s deflated tires myself  (I won’t hand an essential tool to a complete stranger) the speed and ease of the full size pump makes me that much more willing to help cyclists in need.

Proceeding with the tire repair, I cleaned the area of the tire puncture (I’m not too proud to say that I licked it) and then I roughened the area with a bit of fine sandpaper (which comes with all patch kits). I then used a permanent marker to draw an “X” through the puncture (any colour will show on the tube).

In my case, I choose to fix the puncture using a glueless patch, which is only “glueless” in the sense that no contact cement is involved. The patch is a small disc of clear plastic, pre-coated with a bonding adhesive on one side.

All that is involved in applying a glueless patch is the aforementioned cleaning and roughening of the puncture area followed by peeling a glueless patch off of it’s smooth backing sheet and carefully pressing it flat over the puncture and then pressing it in place with even pressure for a full 60 seconds.

The puncture is then sealed unless something went wrong — and I must say that more things have gone wrong with my classic contact cement and rubber patches than with the glueless variety.

I’ve been using glueless patches for over three years now and maybe five times I’ve had glueless patches slowly come loose a few months after they were applied and once I had an old batch that stopped adhering properly altogether.

I prefer the glueless patches because they are reliable enough and they are very fast to apply.

Reversing the process

Once the tube was patched I slightly inflated it so that it just barely maintained a tubular shape and then I pretty much reversed the process I used to remove it.

Before putting the tube back inside the tire though, I thoroughly finger-checked the inside tire wall, in case whatever caused the puncture: nail, sliver of glass, staple, et cetera was still lodged in the tire, ready to repuncture the tube.

When putting the inner tube back into the tire, it should go in valve stem first — and carefully. Once the stem is seated nicely perpendicular (straight up and down) in its hole in the wheel rim, the rest of the tube on either side is tucked up into the tire.

Then the outside bead of the tire needs to be tucked back inside the wall of the wheel rim.

I was able to do this with the soft gumwall tire using nothing more than my fingers but with most tires I will at least need to use a tire lever to tuck the last six inches-or-so of bead inside the rim.

When I remove a tire I use the tire lever like a one-tined fork to dig under the bead and lever it up and over the wheel rim. When I’m putting a tire back on a rim, I use the tire lever upside down and insert it under the tire and over the rim and by lifting the lever up I force the resisting tire bead up and back over the wheel rim.

I checked carefully to make sure that both tire beads really were fully and firmly in the channel between the wheel rim walls.

Then I fully  inflated the tire — and then some.

It is my practice to initially over-inflate a tire with a new (or replaced inner tube) in order to “seat” the tube in the the tire. I inflate the tube enough to make sure that it completely fills and presses against the inner wall of the tire. The rubber tube then grips to the rubber tire and is discouraged from sliding around and damaging the valve stem.

The final step was to put away my tools (jumping up and down on the dead socket wrench a few times) and put the cinder block back where I found it.

And all that before my first cup of coffee! Click the image to enlarge it.

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