Converting from 8 spd to 11 spd for IDT

[Captain Fastbastard Mayhem]

That makes no sense at all. The contact points are all on the inside of the chain.

 

I will concede performance of front derailed will not be as good. But it will absolutely shift. It will just be slower.

Because the chain is narrower, you'll have to move the shifter more in order for the derailleur to make contact with the external face of the chain, so that it can move it across to the next chainring / cog. It'll also have to move slightly more in order for it to make contact with the shifting ramps, shich make contact with the exterior of the chain. 

 

For fitting on the cassette / chainring, internal width matters (which is why single narrow/wide chainrings can accept 10-12sp chains without hassle)

 

For shifting, external width matters. That's why an 8sp chain is too thick for a 12sp cassette, and why a 12sp chain will battle to shift on an 8sp setup. 

[Kona Kula]

Because the chain is narrower, you'll have to move the shifter more in order for the derailleur to make contact with the external face of the chain, so that it can move it across to the next chainring / cog. It'll also have to move slightly more in order for it to make contact with the shifting ramps, shich make contact with the exterior of the chain. 

We are talking millimetres here. 5.5mm - 7mm thats only a 2.5mm difference. Sure the derailure will have to move further, but it will make it.

[Captain Fastbastard Mayhem]

We are talking millimetres here. 5.5mm - 7mm thats only a 2.5mm difference. Sure the derailure will have to move further, but it will make it.

yeah, that is true. But consider that that's essentially an extra half-shift for the 12sp chain... On the back it's less of an issue as it also follows the jockey wheels, but shifts up the cassette will still suffer cos you'll have to push more to get the chain to engage with teh shifting ramps on the cassette.

 

I still wouldn't put a 10/11/12 sp chain on an 8sp setup. 

 

Obv I'm talking theroetically. In practice it may be different, or less of an issue than I think it'll be. Welcome to be proven wrong on this. 

[Pure Savage]

11sp chain won't work on 8sp rings, so it's either chain, rings, cassette and shifter or an 8sp Sunrace cassette.

 

I know what I'd be doing.

Riding outside on the trails?

[Karman de Lange]

Yes but the outer width, the inner width doesn't change. Therefore it will work on any system. Even a 5 speed.

The 7 speed chain did not work on my 10 speed cluster as it rode on the cog next to it. Was simply to wide to fit between adjacent cogs., nothing todo with shifting, was matter of cannot ride in two gears at same time :-)

[Kona Kula]

It won’t work that way correct.