One of the longest runnning problems in the history of cycling, or at least cycling with chain driven machines, is that of oil contamination of clothing. In the last century there seemed to be two principal solutions that were widely available; cycle clips and chain guards. The former are still available, but have suffered from their association with humour of the less reputable kind and so are not for those who are in any way 'fashion conscious'. Chain guards seem to have simply faded away, followed not too much later by mudguards. The cynical explanation must be that these items were seen as an un-necessary expense for cycle vendors trying to turn a better profit margin.
Despite the decline in the solutions, the original problem of oil contamination has not gone away. So, what is one to do to avoid it when one has a machine that does not address the problem? There seem to be two solutions. Firstly, it would be possible to make a custom guard (see the article by Matthias Bunte) or secondly one can search out something ready made.
The Unidisc Trouser Guard
The 'after market' for chain guards seems quite limited. Mixed in with any internet search for 'chainguard' will come a wealth of mountain bike guards that are for protection against rock damage rather than oil contamination of clothing. However, one can acquire, if one knows where to look, complete oilbath chain guards of the type fitted to Dutch bikes. These are excellent, but will fit only a limitied range of applications. Alternatively, eBay sellers offer 'p' shaped affairs that may or may not provide sufficient information to determine their suitability for your application. There also seems to be a limited range of guards marketed for particular brands of chainring. A few bike retailers such as SJS Cyles and Halfords provide useful information like the number of teeth on the chain ring for which such guards are intended.
Fortunately, a bit of further digging unearthed the Unidisc Chainring Trouser Guard. This is a generic product designed for any chainring, up to and including 48 teeth, that provides a good level of protection. It claims to be:
* the first 'universal' chainring protector
* universal mounting system with 2 adaptors
* unbreakable plastic
* fast and easy to fit
Although not a solid disc of plastic, the device only has relatively small cut outs which suggests that it ought to be good at keeping oily chain and clothing apart. The disc is mounted by a single screw which is fixed into one of the two adaptor plugs. The latter are threaded plugs which screw into the crank where normally a dust cap is fitted. The two plugs are intended to cover the two main thread patterns to be found on modern cranks. If neither plug fitted, it would be possible to achieve the same efffect with a suitably trimmed cork since all that is needed is something firm into which to screw the fixing screw.
Fitting and Use
As the brief instructions on the packaging suggest, the device is simple to fit. The dust cap on the chainring crank is unscrewed and then compared with the two plugs. The plug that looks the closest fit is then screwed back in place of the dust cap. Once securely screwed home, the guard is placed in position and then secured with the crosshead screw. This proved to be easy and requred only a flat blade screwdriver to remove the dust cap and a crosshead screw driver to secure the guard. Despite having only one screw, the guard appeared to be very secure.
In our test, the Unidisc was fitted to a chainring of 52 teeth so one would have expected it to be ineffective. This was not the case as the chainring only reached up to near the top of the plastic disc and it was perfectly effective at stopping contamination from sideways contact. Obviously there was a risk of contamination with top contact but this has not been a problem in practice.
The fixing has proved to be secure and it has been very much a case of fit and forget. In our test the disc was fitted to a tandem left hand stoker chainring as this was the one that seemed to be causing the most contamination. There is no front changer on this chainring so it has not been possible to test how the product works with a double or triple changer. From the gap between the disc and the chainring it looks as if there should be plenty of room for the changer mechanism.
Suppliers and Price
The Unidisc is made by Rixen and Kaul in Germany and retails in Britain for around £14. The British tax paying suppliers we have found are:
Practical Cycles, Unit 6, Lytham Trade Park, Preston Road, Lytham FY8 5AT [http://practicalcycles.com/]
Dereks Cycles, Unit 5, SSP Building, Heath Road, Skegness, Lincs, PE25 3ST [http://www.derekscyclesonline.co.uk/]
St John St Cycles, 91-93 St John Street, Bridgwater, Somerset, TA6 5HX [http://www.sjscycles.co.uk/]
This is a simple but effective product that does exactly what is says on the box. Highly recommended.