When to replace cassete

[2good]

hi
Having some problems with my gears.currently have a 9 speed triple road bike,giant defy 3.its a yr old done roughly 700 miles.i changed the chain recently.it was worn.should i have changed the cassette and chainrings aswell?.the back gears are slipping when i put a lot of pressure on the pedals.i.e standing up .im 16 stone!.
i fitted new gear cables but still the same prob.i can index the gears on the workstand fine.
Cheers

 

[bonker]

750 miles!! That's a short life for a chain. But basically, yes, change the chain and cassette at the same time, after miles and miles. Anyone who says a chain only lasts 1500 2000 miles has got more money than sense.

 

[gbb]

750 miles!! That's a short life for a chain. But basically, yes, change the chain and cassette at the same time, after miles and miles. Anyone who says a chain only lasts 1500 2000 miles has got more money than sense.

750 miles is low...mind i consistently only get 1200 miles to a chain..perhaps OP can elaborate what chain lubing regime he's using .

As for cassettes and when to change...
There's several schools of thought.
Replace chain at 0.75%, replace the cassette every 3 chains. That works for me.
If you let the chain wear up to and beyond 1%, you'll increase the wear on your cassette, requiring it to be replaced earlier.
Some people let the whole lot run and run until the whole lots cream crackered, then replace it all together.

 

[2good]

Any other reason why the chain wud slip?

 

[asterix]

On my Roberts the chain has lasted 1000s of miles including the Raid Pyrenean last year. I decided when the time came I'd replace the whole lot if need be rather than faff around putting new chains on.

 

[Broadside]

I replaced my most recent chain after 4000 miles, just very very slightly past 0.75 certainly nowhere near 1% and it slipped like crazy on the old cassette. New cassette and it's all sorted but in future I will be replacing the chain before 0.75 so I can get the cassette to last for 2 or 3 chains.

 

[yello]

I've recently had a similar experience to dmoran above ^^

In my case, I put the old chain back on to resolve the chain slipping problem. My chain also was not yet at the .75 wear mark but it has done 7500k now! I will be changing chain and cassette soon.

This is probably blox, but I wonder if cassettes wear just sufficiently to not look overly worn to the eye but enough to not mesh properly with a new chain.

 

[amaferanga]

I've done several thousand miles on a Shimano 105 cassette. Been through 4 chains (I think), changed every couple of thousand miles or so. If you're looking after your bike then there's no way a cassette will be worn after 700 miles! And unless you smothered your chain in grease and rode on the beach every day then there's no way a chain should only last 700 miles either.

I would question whether you actually have the got the gear indexing right and also if you are measuring the chain length correctly.

Might be the pawls in the freehub sticking I suppose - have heard of it happening intermittently and only in certain gears.

 

[byegad]

Assuming the indexing is correct, it's time to change the cassette when a new chain skips as you describe.

I refurbished the last of my upright bikes, (I've been advised to stay off two wheels, so ride recumbent trikes now.) last week, in order to pass it to my daughter in law. The chain was surprisingly, I'm usually good at these things, well worn out easily failing the 1% side of the go/no go gauge I have from Park Tools. So I fitted a brand new chain, and it skipped like mad. A new cassette later and it is fine.

Lesson?

Check the chain for wear and change at 0.75%. When I've done this the cassette lasts at least three chains.

As to the chain being shot after 700 miles, that sounds like you were mashing the pedals, a lot, and hadn't used any lubricant in the three years. I tended to get 2-5000 miles from a chain on a DF with fairly minimal care, just keeping it clean and lubed when it looks bad. Most of my chains look grubby most of the time!

Cassettes vary in quality. The cheap and cheerful ones tend to be made of steel and last a long time, but are heavy, the more you pay the slicker they change and the lighter they are, BUT as you get to the very expensive ones they sacrifice weight for durability.

Edit...After thought.

I have in the past removed and replaced a rear wheel and the indexing has been way out. Removing and replacing it again has got it back to normal. Try that before investing in a new cassette.

 

[gbb]

Assuming the indexing is correct, it's time to change the cassette when a new chain skips as you describe.

I refurbished the last of my upright bikes, (I've been advised to stay off two wheels, so ride recumbent trikes now.) last week, in order to pass it to my daughter in law. The chain was surprisingly, I'm usually good at these things, well worn out easily failing the 1% side of the go/no go gauge I have from Park Tools. So I fitted a brand new chain, and it skipped like mad. A new cassette later and it is fine.

Lesson?

Check the chain for wear and change at 0.75%. When I've done this the cassette lasts at least three chains.

As to the chain being shot after 700 miles, that sounds like you were mashing the pedals, a lot, and hadn't used any lubricant in the three years. I tended to get 2-5000 miles from a chain on a DF with fairly minimal care, just keeping it clean and lubed when it looks bad. Most of my chains look grubby most of the time!

Cassettes vary in quality. The cheap and cheerful ones tend to be made of steel and last a long time, but are heavy, the more you pay the slicker they change and the lighter they are, BUT as you get to the very expensive ones they sacrifice weight for durability.

Edit...After thought.

I have in the past removed and replaced a rear wheel and the indexing has been way out. Removing and replacing it again has got it back to normal. Try that before investing in a new cassette.

Blimey, i forgot about that possibility, its happened to me before as well.