I am starting to show my age – for example, I no longer think that trouser clips are embarrassing and wear them whenever cycling. Often I can't be even bothered to take them off when walking into a shop. But my daughters, who think differently about fashion and vanity, believe trouser clips are definitely 'uncool'. Arriving at ballet school on a bike is unusual enough but gets significantly more attention on a tandem. To make matters worse, as stokers they need protection from oil on both legs and the latest fashion of 'flared' jeans presents a further challenge to those who want to cycle in normal clothes. So, I started to sew trouser bands in black Velcro, which at least are less conspicuous than reflective, metal clips and these were quite welcomed.
But I thought it should be possible to do better, remembering that on my first tandem tour 30 years ago on a Raleigh tandem, the long oily, ugly chain was fully enclosed. I believe only one chain guard is professionally made these days and only when the connecting chain is on the right hand side (by www.zweipluszwei.com on their 'City', no picture available) So I started to design my own, intending to as a welder to produce something including brackets to fit low on the seat posts near the bottom bracket shell. This is not easy as, due to the chain adjustment via the eccentric bottom bracket, the whole structure needs somehow to be extendible. However, I soon discarded this idea as even thinking about how to describe this to a welder who may not be a tandem rider gave me a headache. So I thought it's best to use as many existing materials as possible. German manufacturer Hebie (www.hebie.de) makes, among other things, chain guards for the right hand side and offer brackets that fit under the end cap of the the bottom brackets. Mine are FAG and have a 'lip' on both sides, protruding the bottom bracket shell, that allow the use of the brackets on the left hand side too (the front bracket that fits the eccentric bottom bracket, needs to be filed a bit). Then I took two of their double winged chain guards (No. 355 in their English online catalogue), turned on backwards and one upside down and joined them together. They are tapered and I had to saw off the bottom wings. Additionally, I had to cut a bigger circle in each guard as the existing circle is slightly funnel shaped and rubbed on the chain wheels. A couple of further cuts were needed to accommodate the left hand chain stay and the stand. The plastic is good quality and sawing with a hacksaw is easy. For stability and distance to the chain I used a downpipe clip with a 'T' ending from a DIY shop, fitted to the keel tube, and extended both bars of the 'T' to fit the guard. Later, when the the chain tension needs to be adjusted that chain guard needs adjusting too, which can be done by joining the guards together again with a new hole and screws, or by creating something more permanent with a long hole that enables the guards to slide along each other.
The right hand side, standard chain case (No. 368) should have been easy to fit. It's specified for 48 teeth and I thought my 50 teeth chain wheel would fit, but that did not allow for sufficient movement inside the case and, additionally, the 4mm distance between the outside front of the dérailleur and the inside of the right hand crank did not give enough clearance so that I will use a simple chain wheel protection for now. Later I might fit a smaller chain wheel, or do the sensible think and upgrade to the Rohloff speedhub. Then I can fit Hebie's double winged chain guard (No. 355) or even the elegant fully enclosed Chainglider.
If I did it again, I would use the single winged chain guard (No. 380) for the rear which saves chopping off the bottom wing. Other options would be to cut both wings of the chain guards that I have used, shorter, and use plastic pipes to cover the chain like recumbent cyclists do. Fitting of the pipes could be achieved with several of the above mentioned 'T' clips.
Other chain guards to consider to build your own for the tandem would be the Country of Utopia (www.utopia.fahrrad.de/Zuberhörshop) but the lady at Utopia informed me this only works with 'pressed' cranks whereas my Shimano Deore ones are 'bolted'. It's not cheap at 150 euro per guard and you need two of them of course. Or check at www.noell-fahrradbau.de/Markplatz.Kettenschutz.total.
Overall, I am quite pleased with my result and, despite the complications I mentioned above, I think it should not be too difficult to produce something professionally for the left hand side. Maybe St. John Street Cycles would like to do this?
Thanks for technical support and ideas from Peter Barzell of www.velopress.de. If someone needs further information please contact me on m_bunte at hotmail.com.
© 2006 Matthias Bunte
This article first appeared in the Tandem Club's Magazine [www.tandem-club.org.uk]