Hello all,

I just got a new 7-speed cassette installed on my commuter bike.

I am using my old Sram PC850 7/8-speed chain with it. I estimate I have put around 1700-1900km on the chain since it was new about a year ago. My chain wear indicator says the chain is 0.5% worn, but not yet 0.75% worn. Was using this chain with a pretty worn freewheel.

I have noticed my drivetrain is not as smooth as I'd like with the new cassette, even when the chain is freshly lubed. A few sprockets give me a kind of "crunchy" feeling when pedaling, while others are perfectly smooth feeling.

Time to replace the chain too?

Thanks!

New cassette or chainring - always new chain unless it only has a few miles on. Saving on the cheap chain is false economics.

Thanks for your response! Yeah, in my mind it was still "new enough", but when I did the math, I've actually put a decent amount of miles on it!

I guess now I am looking for a good quality chain. The KMC X8.99 seems really good (KMC's top of the line 7-8 speed chain), I found it for $13 shipped. I really like the missing link.

An old chain will wear the cassette to match very quickly. Always get a new chain for your new cassette or freewheel!

I always do new chain with a new cassette or freewheel. Not worth it to try to get a few more miles on the old chain and cause unnecessary wear on the new cassette IMO

Toss your chain checker and measure your chains with a good steel rule.

Chunk the chain gauge and get a ruller. Replaceat 1/16" wear (1/2 %).

The Precautionary sort extends the cassette, life with frequent chain replacements,

or as others offered cassette & chain go together.