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Ok, I need new chain for sure, two links have split, and I've over 1200 miles on this chain and cassette combo... but do I [i]need[/i] a new cassette?!
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Fix the chain and carry on or new cassette and chain
Looking at the shape of those teeth, I suspect you may have issues with just a new chain.
parkesie - Member
Fix the chain and carry on or new cassette and chain
Thought about that but won't the chain have stretched and new links be all wrong?
I always change cassette and chain at same time.
Either you replace the chain before it reaches the wear limit, in which case you'll probably get three chains per cassette. Or keep on riding until you get a catastrophic failure and replace both at the same time.
all you can do is buy a new chain and see how well it fits. If it doesn't work then you'll need to get a new cassette as well. You'll probably find by this point you need new chain ring(s) as well, so may as well replace the BB whilst your at it!!
Why would you need to replace your BB because of a worn drivetrain?
Replace the damaged links with quick links and carry on, I'd say. Cassette looks OK to me.
I find that changing the chain at 0.75% usually I can use the cassette for a few chains. 1% and it won't work.
That cassette looks visibly worn, I would just replace it and save yourself a chain slipping ride to find out that you need to replace it. Check the condition of the chainrings too.
One or two new links would be fine (your pitch difference won't add up to much over one or two links but will over several links which are in contact with the sprockets) if you want to run the current set up into the ground then replace the lot at a later date.
Cheers all