9-speed front mech + 8-speed chain?

[Ziggy]

Anyone tried the above? Struggling to find a suitable mech for my GT - I've now discovered that I need a top-swing bottom pull 31.8mm mech, and there's not a lot around in 8-speed...

I'm tempted to give up & get a 9-speed cassette/chain! Sure I've got a spare shifter somewhere...

 

[Wytze]

never had problems with a 9speed frontmech in combination
with 8speed, I also use 9sp rearmech XTR's for 8speed and the front
chainrings are also often 9sp.

Just try it you can always swap it if it doesn't work

 

[cchris2lou]

I use suntour thumbshifters xc pro 8 spd, with an XTR rear mech 9 spd , a front DX mech 7 spd and a 8 spd Sram chain , and it works .

 

[Agency_Scum]

Yeh, no problem.

 

[Ziggy]

I use suntour thumbshifters xc pro 8 spd, with an XTR rear mech 9 spd , a front DX mech 7 spd and a 8 spd Sram chain , and it works .

The issue's that 9-speed front mechs are narrower (I think!) to suit the narrower 9-speed chain... Your set up should indeed work fine as far as I can see!

never had problems with a 9speed frontmech in combination
with 8speed, I also use 9sp rearmech XTR's for 8speed and the front
chainrings are also often 9sp.

Just try it you can always swap it if it doesn't work

Glad to hear that! I'll just get a 9-speed mech if I don't find an 8-speed one soon - just thought I'd check whether anyone else had tried unsuccessfully to do the same thing first: XTR's annoyingly expensive!

I'm already using 9sp chainrings & rear mech without problems, so like I said, I could always swap the rest... maybe a 9sp front mech's the best way to go.

Cheers!

 

[andrewl]

I ran for 12 months or so like this one one bike and it works but the wider chain does mean that the setup isn't as good as a pure 8 or 9 speed setup.

I found that setting up for the granny middle change meant there was some rub for the big ring. With a bit of time and effort you can get it pretty good, although it pays to avoid bad chain angles ie big to big.

 

[andrewl]

Forgot to mention that some of the older Deore front derailleurs which use the screw to join the cage at the rear can be easily modified to make the cage the correct width too.

 

[LTS Biker]

It also works the other way, 9 speed drive train, with a 8 speed front mech.