How much rust is too much? I need to answer this question before I invest time and money in restoring my Wester Ross road bike: if the frame is, or will soon be, compromised by oxidation, then my restoration won’t be rideable! Ideally, I’d make my decision by weighing the expected enjoyment I’d get out of a restored bike against the expected cost of its restoration and proceed with restoring if \(E[enjoyment] > E[cost]\). With the internet, the costs are easy to estimate:
| component | cost |
|---|---|
| Sandblasting | $100 |
| Powdercoating | $300 |
| Adding mount points | $200 |
| Decals | $20 |
| New cables & housing | $30 |
| New saddle | $100 |
| New bottom bracket | $40 |
| Fenders & tires | $150 |
| New cassette | $60 |
| Rust protection | $100 |
| Racks & bags | $300 |
| Total | $1,400 |
I first think about what else I could buy for $1,400: another beautiful old bike, perhaps one that accepts centerpull brakes, 40mm tires, and 650b wheels. In other words, a frame better suited to my frame and my life. But that’s why I have 2 bikes. As bikesnobnyc has said, sometimes the sacrifices of a road bike are all you need. Anyways, back to the bike at hand: for $1,400, I want at least 5 years of use out of the frame. I probably ride the bike 50 times a year, so 5 years would make 250 rides at the cost of $5.6 per ride.
It feels perverse to commodify each ride; part of why I like riding bikes is that, once you’re on, it’s free—free to ride, free to park, freeing to go fast. But even a free bike doesn’t cost nothing. There’s maintenance, gear that you wouldn’t own but for the bike, places you wouldn’t eat if you didn’t ride there. Every so often, summing the costs makes sense.
However, my intent to ride for 5 years is not the relevant question. The relevant question is can I ride this bike for 5 years? In 2025, this bike will be half a century old, plenty of time for rust to do its work. For those unfamiliar, steel frames are basically good for life—unless they crash or rust.
Rust is a tricky thing to evaluate. You can see when it’s not there but when it is there it’s not clear how much rust there is. Has the rust infiltrated the tubing, with the only thing keeping the frame from cracking in half the binding force of paint and dirt compacted over decades? If so, the bike will soon be toast, worth only its components.
Of course, seeing infiltration means seeing inside the tubing, which really isn’t possible without taking apart the frame. Luckily, Redditors have developed ways of detecting the latent oxidation. Here’s 3: 1. Tap the frame with something metal. Rusted out spots should sound quite different than the rest. 2. Peer down the seat tube. 3. Rub a wire brush along the rusted spots to see what all comes off and get a closer look at possible pitting.
I tried all of these tonight at the Somerville Bike Kitchen with mixed results. Tapping the frame yielded pretty much nothing, as the change in tube diameters confounds what differences there may be in rusted spots. I suppose this might work for really serious cases but not for moderate ones, which is where I figured I might be.
Peering down the seat tube was actually a huge relief. Not only did it look okay, there was actually a really shiny piece at the bottom! Turns out this bike got a cartridge bottom bracket replaced recently and it looks even more recent than my purchase. I couldn’t see below the bottom bracket (of course) which would have told me about rust there. That would have helped because its there were you’d expect the most moisture to collect.
Rubbing a wire brush has its expected limitations—you don’t learn about the inside—but fellow bike chefs said it didn’t look bad. With all this knowledge, all that’s left is the ultimate test of removing the bottom bracket! Stay tuned for another post describing my plan for this restoration. I had already scoped out the work needed to give this bike all the glory it deserves, so I would have been heartbroken to see it scuttled.