Originally Posted by
stapfam
Upgrade time and if a 105 has been used- Time to replace. My 105 cassette did not last more than 2,000 miles- wheras the Ultegra has been on for 3K and still good.
And as no-one has given an answer to not changing the Front Derrailler- I still have an 8 year old ACERA (Just about bottom of the lowest you can get) F.D. on the MTB that shifts perfectly and has no sign of any wear in it. Unless you NEED instant changes- The front deraiiler is fine. And better changes will come from Experience and Better brifters.
I have had the opposite experience -- my 105 casette with all else Ultegra shows almost no wear. Casette longevity is closely tied to chain inspection, I suspect.
If the casette is worn, upgrade if the cost is not too different. If the casette is fine, stick with it.