Chainrings???

[Tilt]

Why would, or might a chainring that is described as 9 and 10 speed compatible, not be compatible with 8 speed???

https://www.wiggle.co.uk/ta-110-pcd-zephyr-outer-road-chainring-50-56t

It has the same BCD / PCD circle diameter as mine.

 

Cheers for any input.

This is the identical but inner ring and is described as 8 speed compatible.

https://www.wiggle.co.uk/ta-110-pcd-zephyr-inner-road-chainring

[olduns]

chain width?

the rear cassette spacings get closer the more there are.

i 'think' it goes:

6,7,8 compatible

9 &10,

11&12

 

* I am not a bike mechanic

[olduns]

https://bike.bikegremlin.com/1220/1-bicycle-chains-compatibility/

[MikeTheThinker]

7 minutes ago, olduns said:

https://bike.bikegremlin.com/1220/1-bicycle-chains-compatibility/

Excellent article, thanks!

 

One of my tasks at my folks' place is to make sense of ten or so "project" bikes left here by he who shall remain nameless (not my dad) ...

 

[J.R.]

What goes around comes around!

[NJRJ]

8 sp = indestructible*,  9/10 less so, 11 more fragile, 12spd I wouldn't buy.

 

I had 8spd back in the day, and I never changed anything (5 years?). 9 spd for chain life was once every 2yrs (and I'd got fitter/rode more) the wear showed as over 0.5% (on a cheap gauge) but less than .75% mark (so 1/16"- 3/32" on a 12" length, this is visible pin to pin on a good steel rule) or I might need new a new cassette (but you just swap your chain and if it skips you swap back and ride the old chain/cassette combo to death).

With 10spd it was way more fragile for chain life , and .5% was sooo often, maybe yearly.

BUT with 11spd it has been a disaster, a chain last 3,000 miles at best (so 1/2 annual mileage), and needs doing without fail or it's a new cassette within weeks of missing the swap, AND all this assumes decent chain care and regular re-lube.

 

I hate 10/11 spd, and I wouldn't touch 12 spd as chains and cassettes are getting so much thinner to pack more redundancy gears in...

 

* I was weaker and did less **

** I'm lighter and do more, I'd like to think I'm stronger but I doubt it, match fit maybe...

[Tilt]

Thanks for the replies guys....

 

It's the outer front ring (in the links I posted) that is described as 9 / 10 speed but not 8 speed.........I cannot see chain width affecting this. But the identical make middle ring IS described as 8 / 9 / 10 speed....... I could possibly understand chain width affecting this one.

 

My thinking is if the identical make inner / middle ring is 8 speed compatible then the outer ring should also work fine.....

 

I use a 9 speed chain on my 8 speed road bike also.

 

At present it has the Compact set up 50 / 34 which is a little low geared for me so hoping to go to 52 or 53 / 39 somewhere Mid Compact to Standard set up.

 

The 11 / 28 cassettes are a bit like rocking horse poop at the moment too, Lol.

 

Cheers.

[KenONeill]

17 hours ago, Tilt said:

outer front ring (in the links I posted) that is described as 9 / 10 speed but not 8 speed.........I cannot see chain width affecting this.

 I think (from thread and links) that maybe the outer chainring is thinner than the middle one? This may cause adverse wear with an over-width chain.

[Tilt]

6 hours ago, KenONeill said:

 I think (from thread and links) that maybe the outer chainring is thinner than the middle one? This may cause adverse wear with an over-width chain.

 

Well luckily I already use a 9 speed chain as mentioned so this will not be an issue......... That could be the reason though if they are different thicknesses.

 

I've ordered the inner 39T one now anyway, going to source a new cassette hopefully so to 11 / 28 and will see how that set up goes and will consider then if I still feel the need for a bigger outer.

Most seem to think that it will all work fine, including in the linked article........

 

Cheers.

Edited 9 April, 2021 by Tilt