Fixing the Diamondback Bike

This is a frivolous post on bicycle hardware, so you can ignore it.DiamondBack

Behold, my Diamondback in all her glory. The other day I was feeling energetic and I went out and got the front wheel for this thing. After removing the black rubber rim tape, I took down a large roll of cork. That big wide roll of cork sheet was a freebie from someone who was cleaning out the garage after her husband died. He had been a truck mechanic and she wanted me to haul off as much of his stuff as I would take. Someone else got the tools, but a lot of his specialty supplies were left, and the cork sheet for making custom gaskets was a part of that pile.

Using scissors I cut a trio of thin strips. You see, the rims for hybrid bikes like this, when viewed in a cross section, have a rather deep narrow valley where the butts of the spokes are seated. As I noted in a previous post, some inner tubes will extrude themselves nicely into that valley with no problem. However, near the valve stem of every tube is a sensitive area and they build up the rubber to make it stronger. Unfortunately, this thicker rubber doesn’t fit nearly so well into that tight valley with the valve stem. The vast majority of trouble I’ve had with tubes and tires is right there, where tubes tend to blow out. So I cut these narrow strips of cork sheet and fitted them down into this valley with a tiny bit of tape holding the strips together at the ends. Then I carefully cut a valve stem hole that was a little tight on purpose.

This allowed the valve stem to come through, but that sensitive area is no longer extruded into the valley because the valley is filled with cork. At least, that’s the theory. It worked pretty well on the rear wheel and I just never got around to doing that on the front until last week. The rear hasn’t flattened in months.

So today I went searching for a replacement tube. I went to several stores that sold the bikes, too, but all they had was the narrower road-racing type tubes or Presta valve tubes. My bike has fatter tires and Schrader valves. All those stores in Midwest City don’t even sell a single bike with Presta valves, but all their fatter 700C tubes had Presta valves. On the fourth try I found a store with a large stock of everything — but only two that would fit my bike. I bought both.

Took the time to get the valve seated completely in the cork and aired it up. If it’s still holding most of the same pressure tomorrow, I’ll take it out for a long ride somewhere. There are two reasons for bothering.

1. The old mountain bike is showing signs of hard wear. It’s six years old and, especially the past few months, I’ve been running it hard three days per week. Some of the more expensive components are hard to keep properly adjusted. It’s getting hard to find those components these days and more expensive than ever.

2. The Diamondback offers far less roll resistance; that means more distance for less work.

Granted, I do have to sit upright, which explains the moderately high-rise handlebars. If you click on the picture you can see it up close. After trying to use the stock bar, I started having lots of arthritis pain in my elbows, so I had to replace it with something that would take the weight off my hands. This is the biggest frame (19-inch) that fits my height at around 70″ (1.78m), so it’s a longer stretch away from my body and that put my elbows in a bad pressure angle.

I added the rear rack, the pop-off fenders and built that custom front bottle holder. It’s just a plastic jar mounted on a carefully bent steel strap, held in place with a hose clamp. The ugly parts are covered by the same tool bag I used on the other bike. This bike was on sale because the shop was dumping this model.

If all goes well, I’ll have some pictures from tomorrow’s ride.

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