Chain Wear

trevorh

Bought myself a chain wear tool as I will be looking to replace my chain and cassette myself once they get a bit worn. Do I replace at 0.75% wear or 1%? The "tooth" doesn't quite fall all the way into the space between links at 0.75% but does with a little bit of pressure (only a little). Also my cassette was replaced with the last chain change at the start of September so should I replace that as well or wait until the next chain?? Any help really appreciated.

cooldad

Personally I would throw the chain wear thingy away.

fenix

I think 1% is too much. If its almost 0.75% I'd get a new chain on - chains are cheap compared to the cassette and chainring.

(must measure mine !)

trevorh

Do I replace the cassette at the same time??

redvision

trevorh wrote:

Do I replace the cassette at the same time??

Not if you change the chain before it's too worn.

Usually I get through 1 cassette for every 3 chains (I change each chain at 0.75)

If you put new chain on and you find it slipping then, assuming the chain is the correct length, the cassette will probably need replacing.

fenix

No the idea is that the chain is the consumable - replace that before its too worn and the rest of the kit will last years.

shaw8670

Change the chain just before 0.75, then when the new chain gets near 1.0 put the old one back on and ride it until it is done, Then but a new cassette and 2 chains in readiness to do the same again. You will have a good running and economical drive train this way.

joe2008

shaw8670 wrote:

Change the chain just before 0.75, then when the new chain gets near 1.0 put the old one back on and ride it until it is done, Then but a new cassette and 2 chains in readiness to do the same again. You will have a good running and economical drive train this way.

I change at .75. A cassette lasts many, many chains.

I can't remember when I last changed a cassette, they don't wear too much as long as you keep an eye on your chain.

Bergwerk

redvision wrote:

trevorh wrote:

Do I replace the cassette at the same time??

...
If you put new chain on and you find it slipping then, assuming the chain is the correct length, the cassette will probably need replacing.

Give it a few miles after fitting a new chain though. Often a new chain wil slip a couple of times after mounting and settle in afterwards for many trouble free miles. If it keeps slipping after 2 rides, yep: new cassette time.

The Rookie

With the above, change the chain just before or at 0.75 and the rest of the parts will be fine, if its gone over 1% you may as well ride the lot into the ground as a new chain will probably slip badly. Of course they do need changing eventually!

trevorh

When would I ideally need to change the chainrings and how do I measure the wear on those?

The Rookie

You'll know, when a new chain slips on the chainrings it's time to change.

The single chainring (alloy) on my commuter was just over 5000miles old when I removed it because I was using a better crankset.

dizzydane

I replace my chains at 0.75 (or just before)... The cassettes have lasted years. 8yr old bike has had one cassette replacement in its lifetime. But, I am a bit OCD at keeping my bikes clean so road bikes get a clean and chain wipe down every weekend - after Sat and Sun rides of approx 4-5hrs.

Every now and then, compare the teeth of a new cassette to the one on your bike. You can see the level of wear and tear. When the cassette starts to wear, as the others have said, the chain will start to slip ever so slightly.

wishitwasallflat

Check regularily after 75% and replace once it is 1% myself and I always get four chains to one cassette. Approx 1.3 to1.8k miles per chain as I recall. Not too scrupulous about cleaning and I ride all weathers. Only once changed chainrings and as I recall they had 10k plus miles on them.

PS used to use a chain bath cleaner with degreaser ,now I just run chain through a rag sprayed with gt85 or wd40 and Ive found no difference in lifespan at all. Chain does look lovely for ten minutes or so after the bath though!

hambini

I replace my chains at slightly above 0.75%. I do find that when it gets to 0.75%, the stretch after that is quite rapid.

Everyone is different and you might find that if you pedal with a high cadence and not much torque you'll get a lot of chains per cassette. I usually get 3000-4000km per chain.

hsiaolc

Fenix wrote:

I think 1% is too much. If its almost 0.75% I'd get a new chain on - chains are cheap compared to the cassette and chainring.

(must measure mine !)

Not true about the chainring.

drshoe

cooldad wrote:

Personally I would throw the chain wear thingy away.

How come? how do you measure wear then?

cooldad

After a few years I randomly buy a new cassette and chain.

As long as it all wears together you don't have problems.

I've never had a chain skip, or slip or any other issue. Had a few snap.

And I've been riding bicycles for going on 50 years.

hambini

Drshoe wrote:

cooldad wrote:

Personally I would throw the chain wear thingy away.

How come? how do you measure wear then?

Bike chains are 0.5" pitch which is approximately 12.7mm between each pin/roller

If you count 20 links. you should have a distance between the first and the last pin of 10" or 254mm. The reality is the distance will be slightly longer and that is the percentage stretch.

Here's a video I made explaining:

https://www.youtube.com/watch?v=QF9I6nQ752U&t

hsiaolc

hambini wrote:

Drshoe wrote:

cooldad wrote:

Personally I would throw the chain wear thingy away.

How come? how do you measure wear then?

Bike chains are 0.5" pitch which is approximately 12.7mm between each pin/roller

If you count 20 links. you should have a distance between the first and the last pin of 10" or 254mm. The reality is the distance will be slightly longer and that is the percentage stretch.

Here's a video I made explaining:

https://www.youtube.com/watch?v=QF9I6nQ752U&t

Just use the chain tool please! It's just so much easier and less error.

OF course you can always change after a certain time but thats not very scientific since the bike usage is very different from one and another.

Maybe cooldad only ride once a year and a few years he changes the whole lot. Who knows.

cooldad

hsiaolc wrote:

Maybe cooldad only ride once a year and a few years he changes the whole lot. Who knows.

Yep, once a year. That must be it.

I have a number of bikes for different purposes, mainly mountain biking, plus a short commute, and use mid range parts. So a chain and cassette will cost me under £50. I never actually clean chains, just wash the bikes, wipe and use Squirt.
Never had chains skip or anything, and only ever snapped ones with stupid Shimano pins instead of split links.

I must be doing something wrong. Like being lazy.

Wheelocheese

Just change the chain more often, not the cassette every time, as that's more economical. I usually change my chain 3 times a year/every 1200 miles (ride at a fairly predictable consistent rate), and my cassette approx every 18 months.

svetty

Wheelocheese wrote:

Just change the chain more often, not the cassette every time, as that's more economical. I usually change my chain 3 times a year/every 1200 miles

:shock: :shock: Presumably this is on a 'cross bike ridden through mud all the time?

hsiaolc

cooldad wrote:

hsiaolc wrote:

Maybe cooldad only ride once a year and a few years he changes the whole lot. Who knows.

Yep, once a year. That must be it.

I have a number of bikes for different purposes, mainly mountain biking, plus a short commute, and use mid range parts. So a chain and cassette will cost me under £50. I never actually clean chains, just wash the bikes, wipe and use Squirt.
Never had chains skip or anything, and only ever snapped ones with stupid Shimano pins instead of split links.

I must be doing something wrong. Like being lazy.

Not personal. Just pointing to the OP that not everyone's riding style or condition or frequency is the same so to change chain and casset once every few years is misleading to the OP.

My road bike usage for commute has much more ware and tear than my mountain bike because purely the ride frequency is not the same so even I can't say that I only change my chain and cassette for all my bikes once every few years.