chain worn to 1.0 - can I just replace the chain?

[itboffin]

I recently changed a worn SRAM flattop 12 speed chain, which seemed to fix the shifting problems, only to find the lower 3-4 rings of the cassette skip when any kind of pressure is applied.

Chain was cheap ish but the 10-44 cassette is £90, I’ve had this gravel bike for 2 years and maybe ridden 2000 miles off road, still seems like low mileage for the money.

Compared with my Shimano 11 speed bikes, I can’t remember replacing a cassette on those with 8-10k miles a year, across 3 road bikes that is.

If that is just down to the terrain the gravel bike has to deal with then surely my mtb would also wear equally quickly.

Or could it be that I barely wash my gravel bike ….?

 

[Ming the Merciless]

I change my chain every 5 trees

Not many trees out your way?

 

[Mazz]

I recently changed a worn SRAM flattop 12 speed chain, which seemed to fix the shifting problems, only to find the lower 3-4 rings of the cassette skip when any kind of pressure is applied.

If the new chain is skipping on the old cassette, it sounds like the cassette is too worn and also needs changing.

 

[Ajax Bay]

RD is a Tiagra, so that's good.

your 10sp chain will be fine too as will the RD, unless it's a 4700.

Probably not "good". The 10sp Tiagra RD is the 4700 and it works on the 11sp shift ratio. So 9sp STIs are not compatible

 

[Mazz]

Probably not "good". The 10sp Tiagra RD is the 4700 and it works on the 11sp shift ratio. So 9sp STIs are not compatible

Ah, I was looking for "4700" printed on the RD, but it just said "Shimano Tiagra".
So which RDs are compatible with 9 speed?
Edit...cancel that question, just seen a whole bunch of them doing a Google search.

 

[Katana]

Last time round, I fitted the cassette and chain new at the same time (10 speed). Just measured the chain wear with a 'drop-in' Park tool and it's on 1.0 already.
Do you think I can get away with just replacing the chain?
I guess I'll just give it a go and see if the new chain/old cassette mesh OK.

Assuming it’s shimano groupset, you can get both 10 speed SRAM cassette and chain for £30 approx as they are fully compatible hence saving you quite a bit of dosh.

 

[Ajax Bay]

a 9 speed chain typically last a lot longer than say a 12 speed.

?

If it's 100% true in all cases don't know or particularly care.

Random assertion in an article, with zero basis. And anyway you don't care if it's true or false.

It's obvious as freehubs width remains the same so to fit in more cogs the chain / cogs must be thinner.

Not sure what you think is "obvious".
Freehub widths do NOT "remain the same". Yours are but an 11sp cassette needs an 11sp freehub: it will not fit on a 8-10sp freehub.
The outside dimension (width) of the chains of different speeds get progressively narrower BUT inside dimension remains essentially the same. The link length stays the same (inch) and the roller and pins have similar dimensions across speeds and wear in the same way.
So a differential recommendation to change 10-11sp chains at 0.5% and 9sp chains at 0.75% seems irrational (based on physics - economics (cassette cost) may influence the threshold). Hence my question: "Source?"
Multi-speed chains from 9 to 11 speeds have the same inner width: 11/128″ (2.18 mm).
External widths are 6.7mm, 5.9mm, 5.6mm.
Tests have determined that, in practice, chain rate of wear/elongation depends on its build quality, not on its speed (i.e. its external width).
A bicycle chain durability test

 

[Mazz]

Assuming it’s shimano groupset, you can get both 10 speed SRAM cassette and chain for £30 approx as they are fully compatible hence saving you quite a bit of dosh.

I'd completely forgotten about SRAM, so thanks for the reminder!