When to replace cassette?

[aferris2]

On the assumption that the chain has been replaced at the recommended time, is there a way to tell when the cassette needs to be changed too?
I did 3500 miles on the first chain on my Pinnacle and the current chain has just reached 2500 and I recon it's time to be changed, so should I change the cassette as well or keep the original. There's no obvious visible damage, it just looks "used" compared to the new one.
Bike is a Pinnacle Dolomite 6, so full 105 groupset if that makes any difference.

 

[Drago]

Nice bike, very underrated.

I replace mine ever 3rd chain. Being a manly hunk of rippling muscle chains are usually at .75 at around 1500 miles for me, so I'm in new cassette territory every 3500-4000 miles.

 

[derrick]

I do two chains to one cassette. I did try a third chain once but the gears were skipping all over the place.

 

[raleighnut]

You only need to change it when the gears skip with a new chain.

 

[aferris2]

Nice bike, very underrated.

I replace mine ever 3rd chain. Being a manly hunk of rippling muscle chains are usually at .75 at around 1500 miles for me, so I'm in new cassette territory every 3500-4000 miles.

1500 is the most I got on my Trek hybrid (8 speed) so I was very surprised to get so much more with the 11 speed. Think I will change the cassette as this is chain number 3.

 

[aferris2]

You only need to change it when the gears skip with a new chain.

But will I knacker the new chain if it does start skipping? I only get a chance to do maintenance at the weekend so it would have to survive about 100 miles before putting it right.

 

[Yellow Saddle]

But will I knacker the new chain if it does start skipping? I only get a chance to do maintenance at the weekend so it would have to survive about 100 miles before putting it right.

No.

 

[raleighnut]

But will I knacker the new chain if it does start skipping? I only get a chance to do maintenance at the weekend so it would have to survive about 100 miles before putting it right.

Nah, pop the new chain on and give it a test ride, if it does skip then just put the old chain back on and get a cassette then change the lot next week.
If the cassette needs changing another week/100miles isn't going to hurt anything

 

[Racing roadkill]

I tend to change cassette and chain together. It's not strictly necessary to do so, a new cassette will work with an old chain, but if you try to use a new chain with an old cassette, you will almost certainly find there will be some slippage, until the chain and cassette mesh properly. I use a chain change as an excuse for a new cassette, I may experiment with different ratios as well. Oh my word, how exciting.

 

[derrick]

This is better than 50 shades of grey.

 

[Tom B]

But will I knacker the new chain if it does start skipping? I only get a chance to do maintenance at the weekend so it would have to survive about 100 miles before putting it right.

No.

On my 8spd I usually get 2-3 chains per cassette. I change the chain when worn and replace the cassette when the new chain skips on it.

Last easter I replaced a chain and it skipped, however i was unable to get a new cassette for a few weeks so I persevered after about 150miles it stopped skipping and was fine for the rest of the (usual) chain life. I have no idea what the mechanism for that was. But I am sure YS will be along with a sensible answer.

 

[raleighnut]

On my 8spd I usually get 2-3 chains per cassette. I change the chain when worn and replace the cassette when the new chain skips on it.

Last easter I replaced a chain and it skipped, however i was unable to get a new cassette for a few weeks so I persevered after about 150miles it stopped skipping and was fine for the rest of the (usual) chain life. I have no idea what the mechanism for that was. But I am sure YS will be along with a sensible answer.

that's easy to answer, the sprockets were just starting to be worn and then the new chain 'wore' enough to mesh with them. Chains do not stretch, they wear on the small section of inner link that acts as a bushing.

 

[Racing roadkill]

On my 8spd I usually get 2-3 chains per cassette. I change the chain when worn and replace the cassette when the new chain skips on it.

Last easter I replaced a chain and it skipped, however i was unable to get a new cassette for a few weeks so I persevered after about 150miles it stopped skipping and was fine for the rest of the (usual) chain life. I have no idea what the mechanism for that was. But I am sure YS will be along with a sensible answer.

It takes time for the chain and cassette to 'sync' ( if you don't replace them together ). The teeth of the sprockets on the cassette wear little grooves in the rivets of the chain, the new chain and cassette have not got the 'hand shake' wear, if you don't replace them together, it takes a few miles for the 'meshing' of the chain and cassette to happen.

 

[aferris2]

Well, to whet @derrick 's appetite further, I decided to leave the old cassette on and there's no skipping on the short test run around the village. I compared new and old cassettes and there's hardly any difference in the shape of the teeth (or rather the gaps between). Except for the thickness of the plates, the 25T was the only one that was noticeably different, but only in 2 places.
I hadn't realised before looking closely today that every tooth is a different shape...

 

[Yellow Saddle]

It takes time for the chain and cassette to 'sync' ( if you don't replace them together ). The teeth of the sprockets on the cassette wear little grooves in the rivets of the chain, the new chain and cassette have not got the 'hand in glove' wear, if you don't replace them together, it takes a few miles for the 'meshing' of the chain and cassette to happen.

No. Sprocket teeth never touch the rivets. You've been very generous with very bad advice in this thread. Stick to what you know and don't confuse people who are asking questions that affect their pockets and safety on the road.