I am really anal about my chain tension to the point of madness. If I can’t get my chain just right I throw my bike and sulk like a big baby but I’m not ashamed because I think it’s justified. Some frames have built in dropout adjusters but most don’t so you can either ‘walk’ your wheel back until it’s straight and your chain is taut, force a plastic bottle between your tyre and downtube or just buy some chain tensioners, the absolute dogs bollocks are the NJS stamped MKS ones.
I first saw these at the Cycle Show in 2009 and was instantly struck by their beauty, other chain tugs are huge and ugly but these are tiny little things that could certainly be featured in a design book. As with all NJS stamped parts the quality is second to none and made from the highest quality materials, these are no exception. They fit snugly against the back of your dropouts and are so small that you’ll forget they are even there.
As you can see from the photos they fit over your axle and slip into the dropout, with both on the inside of the frame (as they should be) you may need to pull your seat stays away from each other a bit to get the wheel in. You can use them on the outside of the dropouts if you really have to but the knurled part of your track nuts won’t be gripping your frame then which may cause some troubles.
They feature a double threaded system (see above) which means you can pull the wheel right back to the point where your chain is right and not have anything protruding from the main body. It’s kind of hard to explain but a very clever design, basically there is the part that goes around the axle and then the main body; they are pulled towards each other when you tighten them rather than just one part pulling the other. So with a bit of practice you can position the double threaded bolt at a point where it will stay inside the body, it just looks nicer.
These are without a doubt the best chain tensioners out there and definitely worth every penny for both their good looks and their excellent functionality. They are available from VeloSolo for £27.95 a pair.
NOTE: There are a few different versions of these, the ones in the photos above are the NJS 5mm ones for steel frames, you can also get 8mm ones for alloy frames. There are others that you need to use a spanner with rather than an allen key too.