Monday, April 5, 2010

Spring Tuneup Followup: Noob Mistake

A tip for you, dear reader.

Chains and cassettes wear together. Let a chain go too far, and your cogs will wear to match it. Then, a new chain will skip on the worn cogs -- and you have to replace the cassette too. (In my experience, chainrings are a little more forgiving.) 

More experienced mechanics are shouting "duh!" at me right now, but it's a basic rule that bears repeating. I learned it today when my sparkly new chain absolutely refused to hold the most-used cogs of my old cassette. 

Luckily, I figured it out before I did any out-of-the-saddle efforts, or my dangly bits might have become acquainted with my stem in a soprano-singing sort of way. Ouch.

New cassette from the depths of the parts box: Check! Now we're good to go again.


Anonymous said...

I'll just assume that you learned this many years ago, and it was displaced by the constant stream of knowledge entering your brain. ;-)

This didn't used to be a big deal back in the days when you could replace individual cogs on a freewheel, but with some of the more expensive cassettes out there, a fella has to be aware.

For my high mileage bikes, I actually rotate through two or three chains. The plan is that all of the chains and the cassette will be completely worn out at the same time.

Steve K.
central Illinois

Jason T. Nunemaker said...

Yeah, I should have said that I "re-learned" the lesson. I'm usually good about slapping on a fresh chain before things go too far. This one got away from me.

I think that cassette's going on a decade old, so not a bad service life. It was the last of my swanky XT-level 11-28s, though. Drat.

Steve Fuller said...

This has been in the back of my mind wrt my gravel grinding La Cruz. 2K plus miles in less than a year has meant that the chain needs replacing (per the wear gauge). I have a bad feeling that this might mean a new rear cassette for this particular bike as well. The price to pay for using a bike I guess.