Why do I need a new cassette when I change to a new chain?

[BigonaBianchi]

My cassette seems fine to me??...the LBS are advising a new one because I want a new chain. I dont understand why? They say it will slip on the cogs...erm..why??

 

[Moodyman]

If the chain's stretched beyond a certain point, it will then have stretched the cassette's teeth.

Which means new chain will skip over old cassette. Depends how stretched your chain was when you changed it.

 

[Moodyman]

Duplicate

 

[ColinJ]

You should be able to make your cassette last for several chains if you change them before they get too worn. If you leave a chain on too long though, it wears the cassette to fit it, as I rediscovered to my cost recently. The cassette didn't look that worn, but I only got 200 yards on it before the new chain started slipping. I put a new cassette on and discovered that the chainrings are worn too! It is much cheaper to change the chains more often ...

How worn was your old chain? I'd be tempted to try the new chain with the old cassette and see how you get on, but don't stray too far from home until you are sure that it is okay. You might find that the chain only slips in certain gears, so try them all and give it some welly!

 

[BigonaBianchi]

ok...so the lbs were looking after me then.....i'm planning a transam on this bike hopefully so dont need 'slipage' on the interstate

 

[marshmella]

You should be able to make your cassette last for several chains if you change them before they get too worn. If you leave a chain on too long though, it wears the cassette to fit it, as I rediscovered to my cost recently. The cassette didn't look that worn, but I only got 200 yards on it before the new chain started slipping. I put a new cassette on and discovered that the chainrings are worn too! It is much cheaper to change the chains more often ...

How worn was your old chain? I'd be tempted to try the new chain with the old cassette and see how you get on, but don't stray too far from home until you are sure that it is okay. You might find that the chain only slips in certain gears, so try them all and give it some welly!

So how many miles can you expect from a chain, or does it all depend on the type of cycling?

 

[ColinJ]

So how many miles can you expect from a chain, or does it all depend on the type of cycling?

I think the biggest chain killer is getting them covered in filthy gunk which grinds away at the whole transmission. That's especially true in the winter months when roads have been gritted, doubly so if you haven't got decent mudguards on because your front wheel sprays crap back onto the chain. Even if you have got mudguards, you need a decent mudflap on the front one to keep the worst of the spray off the chain (and your feet).

Gunk sticks to oil so I've recently switched to dry lube to try and keep the chain cleaner. It's early days yet so I can't tell you how effective it is, but so far, so good. (I bought a big spray container of Wurth dry lube from a company on eBay.)

If you prefer to use oil on your chain, let it soak in for a while and then back-pedal the chain through a rag to wipe off any excess. You only need lube inside the chain really, not on the outside.

The chain on my best bike has lasted thousands of miles because I don't tend to ride it in bad weather and I make an effort to keep that bike cleaner. I got through a chain in less than 2,000 miles on my other bike because I didn't keep it clean enough.

 

[marshmella]

I think the biggest chain killer is getting them covered in filthy gunk which grinds away at the whole transmission. That's especially true in the winter months when roads have been gritted, doubly so if you haven't got decent mudguards on because your front wheel sprays crap back onto the chain. Even if you have got mudguards, you need a decent mudflap on the front one to keep the worst of the spray off the chain (and your feet).

Gunk sticks to oil so I've recently switched to dry lube to try and keep the chain cleaner. It's early days yet so I can't tell you how effective it is, but so far, so good. (I bought a big spray container of Wurth dry lube from a company on eBay.)

If you prefer to use oil on your chain, let it soak in for a while and then back-pedal the chain through a rag to wipe off any excess. You only need lube inside the chain really, not on the outside.

The chain on my best bike has lasted thousands of miles because I don't tend to ride it in bad weather and I make an effort to keep that bike cleaner. I got through a chain in less than 2,000 miles on my other bike because I didn't keep it clean enough.

Thanks for that Colin, i've just started using the Mickle method of wiping and lubing the chain, i must admit i neglected the original chain.