So, I popped a new wheelset with a brand-new Shimano XT 9-speed cassette on the back. Now, I'm getting some crazy chain slip, mostly on load, but not always. I'll shift into a higher gear, and it'll slip back to the lower.
Went to my LBS, and the tech said it's either:
1) Chain needs replacing. Measured mine, it's not stretched, but over a year old. Or,
2) Middle front chainring is too worn. Could very well be, I haven't replaced it yet, and most of my riding is in the middle.
So....I bought a new chain, and I'm waiting on the shop getting the middle ring in before I replace it.
My question is: Is this normal after adding in a new cassette? I had no probs with my old wheelset. Buying new parts isn't an issue, but I would like to make sure I'm fixing the prob.