Last night I was attempting to covert my Ultegra 6800 50/34 to 1x. I removed the rings and once I’d found the right length crank bolts fitted a 40t ring. One test ride along the lawn there was a crunching sound and the two pieces of the hollowtech crank have separated.
Did I do something wrong? Are the tabs of the outer ring structural and without the proper ring I weakened it or were they the only thing holding it together and it had already separated when I removed the rings it just fell apart?
It’s not the end of the world I’ve got a new old square paper chainset I can fit I’ve just had to order a new ring with correct bolt pattern. I would be good to know as I was considering converting my daughter's bike and it has the equivalent 105 chainset fitted
You done nothing wrong they can split 🙁
I’ve got a new old square paper chainset
I don't hold out much hope for the longevity of that one either.
Did you refit the cranks "percussively" ? (I do - rubber mallet on the driveside end of the axle). Do sometimes wonder if that's a bad thing ?
Very good, the new one is definitely not made of paper. I didnt have to even remove the cranks or pedals to swap the rings.
this is mine from a couple of weeks ago, theres a split up the back 3/4 upto the pedal with another crack across the back...
