Removing Rust from a Bike Frame


I just wrote a blog about stuck seatposts, and look what happens: the bike I’ve just bought has a seatpost that is stuck solid. Still, all is not lost; I have yet to try all ways to get the thing moving, but the feeling I have is that this one is really frozen. I think the best method will be to try using a pipe wrench, but I have my doubts it will work. The amount of oxidation on this frame and its parts suggests that the aluminium seatpost might very well be bonded to the steel tube. The stem is a different case; it had been adjusted and was extended beyond its safety limit, and when I came to move it, there wasn’t too much resistance. I’m guessing that the seatpost has been in it position for a long time, perhaps even decades.


Image of rusty crank before removing rust from a bike frame



Rust Never Sleeps


Another sign of its many years of sitting out is the state of the pedals. They are both stuck in position and won’t rotate, and I have yet to try and remove them. This could also be another major problem, as stuck pedals can be an absolute nightmare to remove. Both the crankset and pedals have become an awful sullen grey colour, drained of any shine they once used to have. There’s no coming back for these parts, they can be cleaned and polished but the weathering will deny them any glimmer of hope for regaining some of their past glory. The derailleurs have suffered a similar fate; push the shifters..nothing moves.


Image of top tube before removing rust from a bike frame

Progress So Far


The Paint


So far it’s gone as well as I expected. Well, I did harbour secret hopes that once I started removing the rust, the pearlescent finish would reveal itself in all its glory once more. But no, that was never likely. I know from experience that the golden brown oxidation can be removed, and sometimes if it hasn’t been there too long the paint may have survived the attack. It’s the darker shades of rust which are the worst. Nevertheless, this brown rust had been eating away at the metal for too long for any hope of a miraculous recovery. Once the superficial rust was removed, the real damage was revealed: bare steel is now exposed in the so numerous chips to the paint.


Image of removing rust from a bike frame

Top Tube Before and After




I don’t use any expensive chemical cleaners or rust removers for doing this type of job. Firstly, I don’t like using strong chemicals, and secondly, I don’t believe they can really make a significant improvement on what I use already: WD40, soap and water and super fine steel wool. Correct me if I’m wrong. Most of all it just takes a lot of elbow grease and patience to work through all the rust on each tube. This first clean up, which is shown in the pictures, took me nearly three hours. I think it’s looking much better, but it isn’t a revelation. It really needs a respray, but I’d prefer to keep the original paint, even in this condition. I need to have a second go at it, then polish it, and then, maybe, it will look..ok.



Close-up of top tube after removing rust from a bike frame

Left Side Top Tube


The Compromise


To get that awful brown rust off the frameset, you have to carefully clean off what you can until you reach the permanent marks and aberrations left behind. In doing so, you’re going to compromise the finish of the original paint. How can you not? I was well aware of this as I went along cleaning the tubes. It’s either one or the other: clean of the rust or keep the ugly stuff and what remains of the glossy finish underneath. I hate losing the gloss on this frame because it’s such  superb looking frame when its shiny and glossy, but there’s no other way. The same goes for the chrome forks: if you start getting off the rust on them, you’ll lose the shiny plating of the chrome.


Image of first attempt of removing rust from a bike frame

First Clean of Frameset


The Stuck Seatpost


Update, 1 week later: I still can’t get the frozen seatpost to move, though I’ve been limited in my methods as I have a lack of tools where I’m currently staying and what’s worse, the weather has been downright freezing! I’m not very optimistic, to be honest, as all my instincts tell me its hard stuck in the frame. I sometimes just daydream about some crazy way of getting this post out; the joy of seeing it pop out, that satisfying moment of success.. and the sense of revenge that I won the battle. But I can’t see it happening. It’s really frustrating, seeing a stupid seatpost ruin a good bike that could be properly restored. Next week I’ll try some serious, hernia-inducing attempts to free the thing.


Image of seat post clamped by a wrench



Removing rust from a bike frame image of wrench on seat post

Pipe Wrench


It’s Really Stuck


I have my doubts this seatpost is ever coming off. I’ve used the best penetrating oil and used a large pipe wrench, with the help of my brother in law who knows his way around mechanical problems. It hasn’t budged a millimetre. With some seatposts, there’s a big problem of gaining a grip on the smooth cylindrical shape of the post. In this case, the Peugeot’s SR seatpost has a square top, with a square hole running through it where a traditional bracket clamp would be attached. I had the idea of putting a big allen key in there, about 20cm long and 10mm thick, using that hole to gain leverage so I could rotate the post, but no luck. The next step is heat and freezing.


Image of dust cap with washer for removal

Dust Caps


Spiders and God Knows What


In the meantime, I’ve taken off all the rest of the bike’s components. The pedals were tough to remove, but they came off in the end. On the other hand, the dust caps on the crankset were a tricky obstacle. I’ve already made a video about these, and it’s really important to get the first attempt right, and to be as careful and precise as possible with these Stronglight caps. If you charge in in hard and complacent, you may end up never getting them off. I used a large washer with a pair of needle nose pliers, after a good spray with WD40. The drive side resisted but eventually rotated. When I pulled the cap off, there were living organisms underneath, cocoon-like things, pretty freaky.


Image of rusty crank bolt

The bolt and puller


Dimensions and Tools


Sometimes these Peugeots can cause me confusion. If they are early 1980’s, during the transition of the French bike industry to standard threading and sizing, they can still have French dimensions and require different tools. This can be the case for bikes made as late as 1982/3, so I’m never sure with these particular models of Peugeots what to expect. In this case, the bike has standard threading and thankfully I could use the normal 22mm crank puller, not the 23.35mm Stronglight tool. The crank bolt was also 14mm, smaller than the earlier 16mm Stronglight bolts. It always seems easier this way.


Bottom bracket after removing rust from a bike frame

Bottom Bracket


The Seatpost that Won’t Budge


The adjustable cup of the bottom bracket unscrewed easily, which was a surprise ( anti-clockwise for unscrewing ). Inside things weren’t that bad, there was a plastic sheath to protect the cups and I used it for my next job; pouring coke down the seat tube. Because it turns out that heating and dunking in water doesn’t always work in the art of seatpost removal. We tried the method with a professional blowtorch, heating it with a 1500 degree flame, then using iced water to flash cool it. Three times we tried it, but no dice. Below is a picture of the post at present.


Image of stuck seat post

Not Budging


Coca Cola?


I’m going to try pouring coke down the downtube and letting it sit around the jammed seatpost for a couple of days. I’m not convinced that this will work. In fact, I’m down to the final solution, to be honest, which is a hacksaw. Nevertheless, I’ll give the Coca Cola a try, as brute force and shock temperatures have failed.


Image of bike frame after removing rust from a bike frame and Coke







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