Col d’Aubisque – Upgrade Kit

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How’s that for a climb? Not too bad I think. #Excitement

To support my elevational efforts later in 2018, the upgrade kit arrived today. The turbo-boosting, leg-spinning, granny rings of lactic fire are here and nearly ready for action.

Shimano ultegra dura-ace chainring

It seems very strange though, I have to admit. I seem to be turning my sweet-looking road bike into a mountain bike in all but name. I’ve played with a 32T rear cassette for a couple of weeks and obviously there is a difference of the spinny kind compared to the compact I had before. But Richmond Park is perhaps not the best testing ground for my EU adventures later this year. So it probably is nowhere near spinny enough for the Col d’Aubisque.


My ‘new’ bike is built – all the details

Hence the need for some serious work on the front chainrings. Here we have a sneaky 50-34T combination now for the front. Yes! My granny will borrow it. Yes! I will use it too. Nothing is ever quite so easy though as the chain will undoubtedly be too long and the last time I took a link out I managed to twist the part of the chain I didn’t want twisting. Admittedly the time before that I did manage, just fine, but that was when I borrowed a mate’s decent chain link tool rather than the one I seemed to acquire from a former Lidl employee in a car park…or wherever it was. ‘Somewhere cheap’ was where it was probably really from.

Shimano ultegra dura-ace chainring


But the serious job when buying these bits of kit is knowing what is compatible with what. The front of the Shimano packaging handily shows which chain rings are designed to work with each other. And some poor soul has been in charge of the red fibre-tipped pen to make the appropriate mark on each package.

So a 55-34T might superficially sound a very clever compromise for all conditions. But you might have a problem shifting between the notably differently-sized rings and, when in first gear, your chain may well be dragging along the floor…well, nearly. Anyway, that combination is not supported.

  • Front combos: 50-34T, 52-36T, 53-39T, 54-42T, 55-42T, the smallest number being the most spinny
  • Rear Cassette combos: 11-23T, 11-25T, 11-28T, 11-32T, 12-25T, the largest number being the most spinny
  • Shimano give this handy compatibility chart, or you could just call your local LBS
  • In theory I could also change the crank length from my usual 172.5. Let’s not go there ( research on crank length ).

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When you said you were going to travel across from the Atlantic to the Med, i thought you were just going to cycle Gibraltar…


get an e-bike? 🙂