Saturday, 30 April 2016

Cleaning alloy cycle components

I was doing some internet searching in relation to a bike I had to work on for the Springhill Cycle Collection. The bike, an early 1970s model, had been stored in less than ideal conditions and the alloy components were showing signs of surface corrosion - not been cleaned before it was stored. The components were a Spanish copy of Campagnolo and in parody of the great Roman cycling god, the copies were named after the ruler of the Greek Olympian gods, Zeus. Frank Berto in his tome 'The Dancing Chain' doesn't rate Zeus components. Zeus components were never very common in this part of 'the oul sod', so to get a bike equipped with Zeus is unusual. The bike is local, has been ridden and used judging by the layers of dirt and wear to the parts. Anyway to return to the point, the large flange hubs are not Zeus and turned out to be of Japanese origin. I haven't seen photos of this particular model of hub on the web.

However, here at Methuselah Towers I have a confession to make. I haven't bought a news stand cycle magazine in 10 years and don't frequent internet forums, so therefore cannot claim any kind of expertise other than experience. So I have to defer to the 'experts' on the web, who advocate using various grades of abrasive papers and buffing wheels to polish alloy components. Personally I would have grave reservations about such an aggressive approach, as I have experience of alloy components such as Campagnolo and Stronglight cracking and failing. I also don't agree with re-polishing old alloy to a very high surface shine, far removed from the original finish. To me it detracts from the originality of the parts/machine and can, in my humble opinion, be a case of 'over egging the pudding'.

I prefer a more subtle approach, one advocated by a long forgotten source. I was told to use a brass brush to clean alloy and then wipe the surface with oil. I now prefer to use WD40 or an equivalent solvent, on a soft cloth or a bit of kitchen roll, to wipe the burnished alloy. The brush will get rid of the surface bloom and expose the nature and extent of any surface pitting and corrosion. A decision can then be made about re-polishing if deemed necessary. It is surprising how much the brass brush will clean up the alloy, whilst still leaving a sympathetic finish to the metal. Where the corrosion is not too deep it can be polished out after cleaning, using Autosol and a soft cloth. A final clean with a silicone based car polish will give it the final seal as you have in all likelihood removed the original anodised finish. I have tried to show a few before and after photos to illustrate the point. The Maillard small flange hubs are ones I rescued from the scrap bin of a cycle business. 

Remember that you will need to keep an eye on your repolished alloy as it will now be more susceptible to corrosion as the anodised coating has been removed!