Chainset rings

squibnocket Posts: 207
edited October 2011 in Workshop

Not sure if this has been asked before appologies if it has, I have a Ultegra 53/39 chainset, can I change the rings to a 50/34 if required for hilly rides or is a new chainset the answer



  • John.T
    John.T Posts: 3,698
    No. The bolt circle diameters (BCD) are different. The smallest ring you can put on the Ultegra is a 38. Why I run a compact and fit bigger rings if I need them.
  • Thanks for that wish I'd have known that before I got the chainset ah well. Its a pity Shimano don't do something like the Sram Wifli thing I like the thinking outside the box thinking with Sram.
  • John.T
    John.T Posts: 3,698
    The SRAM WiFli is not ideal as it gives wide spaces between the gears which many do not like.
    Your cheapest option is a cheap compact chainset with the same BB fitting as your present one. You would need to factor in a shorter chain to fit at the same time. Then it would only take about 30 min to swap over when needed.
  • Everything has pro's and cons I suppose, I would stick with shimano tho . The Sram just looks/ sounds like a good idea. Maybe a bike for both would be nice :D