9sp Shimano with 8sp chain ?

[andy_wrx]

I'm converting my Winter bike from 8sp to 9sp, have all the bits except the chain hasn't turned-up yet, but I'm getting twitchily impatient to start.

Could I as a temporary thing get away with running a 9sp Shimano (compatible) drivetrain with an 8sp chain ?

(new SRAM 9sp cassette, existing not-very-worn SRAM PC58 chain, 105 f&r mechs and chainset which are currently happily running with this 8sp chain, used Ultegra 9sp shifters from a friend)

I'm assuming that whilst the cog-to-cog distance on the cassette is less and the correct 9sp chain correspondingly a bit narrower, there will be a bit of leeway to allow for the derailleurs not being set-up 100% perfectly, or for things going out of adjustment or wearing, minor cable-stretch, etc.

Twould only be a temporary thing until the 9sp chain arrives next week, so
if I was careful to make sure the derailleurs were set-up absolutely spot-on, will I get away with it or should I restrain my impatience till next weekend ?

(if it turns-out the part-worn chain jumps on the new cassette, that's different issue...)

 

[andy_wrx]

I'm converting my Winter bike from 8sp to 9sp, have all the bits except the chain hasn't turned-up yet, but I'm getting twitchily impatient to start.

Could I as a temporary thing get away with running a 9sp Shimano (compatible) drivetrain with an 8sp chain ?

(new SRAM 9sp cassette, existing not-very-worn SRAM PC58 chain, 105 f&r mechs and chainset which are currently happily running with this 8sp chain, used Ultegra 9sp shifters from a friend)

I'm assuming that whilst the cog-to-cog distance on the cassette is less and the correct 9sp chain correspondingly a bit narrower, there will be a bit of leeway to allow for the derailleurs not being set-up 100% perfectly, or for things going out of adjustment or wearing, minor cable-stretch, etc.

Twould only be a temporary thing until the 9sp chain arrives next week, so
if I was careful to make sure the derailleurs were set-up absolutely spot-on, will I get away with it or should I restrain my impatience till next weekend ?

(if it turns-out the part-worn chain jumps on the new cassette, that's different issue...)

 

[spandex]

Mate dont do it it will not work as you said the chain is a bit narrower. as the space you had the 8sp you now pushed 9 in there and as so you cant get the indexing right it will jump all the time. In the time frame your looking at ie: 1 week you would of started to where down your lovely new block.

 

[spandex]

Mate dont do it it will not work as you said the chain is a bit narrower. as the space you had the 8sp you now pushed 9 in there and as so you cant get the indexing right it will jump all the time. In the time frame your looking at ie: 1 week you would of started to where down your lovely new block.

 

[User482]

Yep, you need a 9 speed chain. But using a 9 speed chain on an 8 speed setup works fine.

 

[User482]

Yep, you need a 9 speed chain. But using a 9 speed chain on an 8 speed setup works fine.

 

[andy_wrx]

Limited myself to just fitting the new BB as it turned-out.

Spent rather more time grovelling about under a toilet which initially wouldn't flush (easily fixed, new syphon diaphragm) but then insisted on bl**dy leaking when I put it back together (three times), I dropped one of the butterfly nuts down inside the floor, etc, etc - nightmare.

And the 9sp chain has now arrived today.
For my own interest, when I swap everything over I'll just try it with the 8sp chain and see if it's possible to actually set it up to run this way, at least on the workstand.
As I now have it, I'll fit the 9sp chain before I actually ride it of course.

SRAM chains seem rather different in width than Shimano

Shimano HG 8 speed = 7.4mm wide
Shimano HG 9 speed = 6.6mm wide

SRAM 8 speed = 7.1mm wide
SRAM 9 speed = 6.9mm wide

 

[spandex]

SRAM chains seem rather different in width than Shimano

you are right

Sram chains dont wear the same as Shimano because of the change in width. Shimano chains wear at the pins which can be checked by a (chain checker). but Sram chains seam to have more flex (side by side) before chain checker will spot the wear in the pins

look at the chain "stretch" part of this link.
http://sheldonbrown.com/chains.html#wear

 

[andy_wrx]

Go up a bit and look at 'cleaning chains'.
Sheldon talks about the difficulty of cleaning Shimano chains because it's difficult to remove and reinstall them, with their special one-use joining pin, then says

If you wish to make a habit of cleaning your chain off-the-bike, the best approach is to buy an aftermarket master link, such as the Craig Super Link. or SRAM PowerLink. These permit removal and re-installation of the chain without tools. The PowerLink is standard equipment supplied with SRAM chains, but it also works on other chains of the same width.

So with those widths I found above, the SRAM PowerLink isn't going to work that well with a Shimano chain !
- must try to find some widths for KMC, for their equivalent 'missing link' system...

Must admit, I went to SRAM straight away for 8sp & 9sp because of the PowerLink and have always been happy with them.
But their 10sp chains use a one-use connector so I'm using KMC for 10sp, because this has the 'missing link'

 

[spandex]

you can buy the special one-use joining pins from your LBS if you do like the Shimano chains?


Did you know the KMC make 150,000,000 meters of chain a year (not just for bikes that is)

 

[andy_wrx]

I think KMC manufacture chains which have the Shimano logo on them

 

[spandex]

they do