Measuring a cassette for wear

[User]

 

[zizou]

I just go with the method of if a new chain slips then time for a new cassette too.

 

[Scoosh]

I've replaced a cassette because it looked worn and the chain was jumping out of the gears a bit.

From BR:

14. Check cassette
Just because cassette teeth are hard steel, they’re not immune from the ravages of wear. In fact, cassette teeth can wear pretty quickly once the chain has stretched, causing similar ‘hooking’ of the teeth as occurs on softer alloy chainrings. As cassettes are expensive compared with a new chain, it’s better to change your chain frequently and save the cassette.

Worn cassette clusters are easily spotted the same way as chainrings. Look for widening of the pitch between the teeth, particularly in the middle five sprockets, and any other bent, missing or otherwise damaged teeth. Remember, though, that sprocket teeth aren’t uniform from new, with some lower and more twisted to provide you with faster and quieter shifts.

 

[MrGrumpy]

imo that looks shot, i.e its not going to get better is it ? Not that I`m super great with changing chains when I should Dunno what cassette it is but if its tiagra equiv, they ain`t dear an neither is a chain. Just change them both ?

 

[Cycleops]

Agree with MrGrumpy, that is totally shot.

 

[Crankarm]

Replace, it's knackered.

 

[jarlrmai]

way worn, that big cog 50% of the teeth volume is gone

 

[MrGrumpy]

so keep going and replace the front chain rings as well

 

[toontra]

I've started using a chain measure tool recently and it has already saved me money, mainly because it's so quick and easy to do the measurement that I can catch the chain before it wears to the point of causing significant damage to the cassette/front rings, which are the expensive bits to replace. Chains themselves are cheap these days, especially if bought in bulk.

I used to grind everything into the ground until I got slipping and replaced it all in one go. I'm pretty sure that was the expensive option!

 

[jarlrmai]

Be careful a chain breaking at speed can be bad if it ends up in the rear spokes, I got lucky mine slipped out at 25mph and all I noticed is it got real easy to pedal.

 

[ColinJ]

so keep going and replace the front chain rings as well

You beat me to it!

I went down this path shortly before a local audax and had to start changing parts just before the ride. A new chain slipped on the old cassette, so I put a new cassette on, but then the chain started slipping on the rings instead! I had to dash home and change bikes.

It is cheaper to look after the chains, and replace them sooner rather than later. (Chains are cheaper than chainrings, and certainly cheaper than the cassette that I use which is £40+.)

 

[zacklaws]

I've started using a chain measure tool recently and it has already saved me money,

I was once told that they can be innacurate and a while back, I had a chain wear quite quickly when I checked it with my measuring tool.....so I double checked with the steel ruler and the chain was still OK and no wear showing. As a rule though I just go by the measuring tool, but it pays to double check. A quick online search brought this web page up, never seen it myself before:-

http://pardo.net/bike/pic/fail-004/000.html

I also once had a brand new chain wear out in 79 miles, so I binned it, but to this day, I think I took the old one off, put the old one back on and binned the new one accidently but when I did it, I had come home straight off night shift so my brain may have only been firing on one cylinder, but there again, it could have been my chain measuring tool giving me a wrong reading.

At the moment, I have a chain which has done more than double my usual 1200 miles and it is still good. I don't know why? Perhaps its time to get the ruler on it!!

 

[uclown2002]

You usually only get 1200 miles from a chain?

 

[Andrew Br]

You usually only get 1200 miles from a chain?

That's about what I get ................... .
What makes it worse is that I'm scupulous about cleaning the chain after a ride.

.

 

[uclown2002]

That's about what I get ................... .
What makes it worse is that I'm scupulous about cleaning the chain after a ride.

.

Wow; that's 3 weeks riding for me!
I got 4400 from my last chain and I've done over 4000 on this one and still less than 0.75% wear.