Worn cassete sprocket

[Blue Hills]

I remember buying a cassette from aliexpress a few years ago and at the time you could order it with a spare 11T cog and I ordered 2 spare as they were only about 40p each on top of the price of the cassette. I think I ended up using one of the cogs with a different cassette as seemed to fit. Zitto brand comes to mind (yes not very inspiring name). Just basic steel cassettes. There are loads of individual cogs on aliexpress but of course whether they match the quality of the original cogs from Shimano and SRAM etc is another matter. Lots of fake stuff there. However I'm assuming my spare Zitto cogs are genuine Zitto cogs.

mm - will look out for zitto - never heard of.
Have bought stuff from China before the customs/tax regs changed but not since. Never bought anything techie or where there might be safety/performance/dutrability issues though.
Great idea about the spare 11T - all manufacturers should make that an option- 11T cogs are a menace - I try to minimse my usage of them - unless in a super hurry I tend to change back down from them and just spin more.

 

[nlmkiii]

Is that merely a commercial reason that they are not sold in singles
To make you buy a full new one
I likely keep the used one and attempt uo use a sprocket from it when the new one wears
Its not for financial reasons...it just seems a waste
So long as that is ok to do

Even if you could, you would likely be wearing the same cogs as you wore the first time more than the ones that aren't worn. So it wouldn't solve the problem. Just need to yeet it in the bin I'm afraid.

 

[Lookrider]

Even if you could, you would likely be wearing the same cogs as you wore the first time more than the ones that aren't worn. So it wouldn't solve the problem. Just need to yeet it in the bin I'm afraid.

I would trade the sprockets I wore out
Against the dofferent sprockets that my mates would wear out as I assume we would wear out different sprockets

 

[Ming the Merciless]

I would trade the sprockets I wore out
Against the dofferent sprockets that my mates would wear out as I assume we would wear out different sprockets

People have all sorts of different preferences for gearing even on same terrain. They may have worn out the same ones, they may not.

 

[Dogtrousers]

Yes I often used to see 11 and 12T sprockets sold separately but it never seemed economic to me

Oddly enough I'd have thought that the 11T is the least likely to get worn out early. More likely to be one of the middle ones.

 

[bonzobanana]

Oddly enough I'd have thought that the 11T is the least likely to get worn out early. More likely to be one of the middle ones.

I think that's normal as there are so few teeth supporting the chain so they typically wear down the fastest and many cassette manufacturers I think only have the two smallest cogs loose with the rest built into the main block. I write that as someone who normally goes for fairly low end cassettes. It might be completely different for higher end cassettes. I'm a bit of a masher/grinder so do wear down the smallest cogs pretty quickly.

 

[Blue Hills]

I think that's normal as there are so few teeth supporting the chain so they typically wear down the fastest and many cassette manufacturers I think only have the two smallest cogs loose with the rest built into the main block. I write that as someone who normally goes for fairly low end cassettes. It might be completely different for higher end cassettes. I'm a bit of a masher/grinder so do wear down the smallest cogs pretty quickly.

yep - wear accelerated due to low number of teeth to spread the revolutions.
And if a bike is low geared you may resort to the 11T more.
May also be bad for the chain.
I may be wrong but I have an idea that some idiot company had/has a cassette with a small cog with less than 11T.

 

[Jenkins]

<snip>
I may be wrong but I have an idea that some idiot company had/has a cassette with a small cog with less than 11T.

SRAM do 10T cassettes for the XD hub and Campagnolo go down to 9 on the Ekar groupset

 

[Blue Hills]

SRAM do 10T cassettes for the XD hub and Campagnolo go down to 9 on the Ekar groupset

agh!
wasn't a nightmare then.
Madness I tell you.

 

[Ming the Merciless]

Oddly enough I'd have thought that the 11T is the least likely to get worn out early. More likely to be one of the middle ones.

Agree you don’t spend that long on 11T and unless Chris Hoy when you do, it’s very little torque being applied.

 

[bonzobanana]

yep - wear accelerated due to low number of teeth to spread the revolutions.
And if a bike is low geared you may resort to the 11T more.
May also be bad for the chain.
I may be wrong but I have an idea that some idiot company had/has a cassette with a small cog with less than 11T.

Also if you are a heavy rider who likes to go fast on relatively flat ground especially with a slight decline in height. Anyway clearly the manufacturers know this is an issue hence the loose smaller cogs unless there is some other reason to do that I haven't thought of. Same with freewheels which have no loose cogs so they pretty much limit the small cog to 13 or 14 teeth because they are non replace-able for decent brands like Shimano. Yes I know you get some Chinese factories that produce freewheels with 11T but they simply don't care about engineering quality. The same freewheels often have pretty ropey internal threads so more pronounced freewheel wobble. Sort of freewheels that are ok for hub drive ebikes but not so great for acoustic bikes.

 

[Jenkins]

This is the wear pattern you get when you tend to use only two or three cogs on the cassette. This is the 10 speed 12-25 taken from my main commuter after about 4,500 miles - have a look at the 16 tooth ring (bottom row, centre) and the 15 tooth ring to its right and compare the shape of the teeth to the rest of the cassette.

This one shows the 17, 16, 15 & 14 tooth rings in a bit more detail

 

[Ajax Bay]

@Jenkins those are excellent images and many thanks for sharing. This will be a 'go to' post when this comes up again. As Ming has said everyone's different (and a large chainring much different from 50t will be the main 'difference') but as I said ^^ the most worn sprockets are normally the 15-17t ones. My case rests, yer hon'r.
To join @Dogtrousers and @Ming the Merciless: the smaller sprockets do not wear nearly so much. I recall a long (120km?) ride where, having replaced a cassette with another 'hardly used' one (but stupidly/lazily not tested it) I set off on fairly flat roads. After an hour and encountering gradients I discovered that the only sprockets that the chain wasn't skating on were the top two and the bottom two (9sp). With a triple I was able to complete the ride. Here is the range I was left. As you can see: entirely doable (Isle of Purbeck).
http://www.gear-calculator.com/?GR=...14,25,28&UF=2215&TF=90&SL=2.6&UN=KMH&DV=teeth