MTB Derailer on Road Bike

mike said:

Can I put a Mountain Derailer on a 10 spd Dura Ace STI with a FSA
Compact Double? And use a 9 speed 34T cassette?

No. You must use a 10-speed cassette.

Quoted message said:

I realize there are no 10 spd MTB derailers available, but could I
make a 9 spd work?. Wouldn't I just have an extra click on the 10
speed STI shifter

No, you can't make it work properly. You would have the extra click on the
shifter, but since the 10-speed shifter pulls less cable than a 9-speed
shifter, you would only be able to shift about 3 or 4 of the cogs properly.
The rest would clatter and skip on you.

9-speed derailleurs work fine on 10-speed drivetrains. The shifter,
cassette, chain, and chainring *spacing* govern how many speeds a drivetrain
is.

--
Phil

mike said:

Can I put a Mountain Derailer on a 10 spd Dura Ace STI with a FSA Compact
Double? And use a 9 speed 34T cassette?

I realize there are no 10 spd MTB derailers available, but could I make a 9
spd work?. Wouldn't I just have an extra click on the 10 speed STI shifter

Thanks
Mike

The RD isn't 9s or 10s, the shifter is. You cannot use a 9s cogset with
10s shifters, the spacing is too different. Using a '9s' RD will not
give you 9s spacing, the shifter determines that.

The only way to use a 9s cogset, MTB style, is to use Campag 10s
shifters, a Campag long cage RD and then say a 11-34 shimano 9s cogset
and chain.

mike said:

Can I put a Mountain Derailer on a 10 spd Dura Ace STI with a FSA Compact
Double? And use a 9 speed 34T cassette?

I realize there are no 10 spd MTB derailers available, but could I make a 9
spd work?. Wouldn't I just have an extra click on the 10 speed STI shifter

You might need an MTB derailleur to clear the 34.

But 9 speed spacing is different. Never tried it but clamping the cable
on the wrong side of the bolt on the derailleur might change the ratio
enough to approach the 9 speed sized steps.

Or use a loose 34T cog, a properly sized spacer and toss the endcog to
make your own 10 sp 34-? cassette. Use a proper endcog though with
serrations for the lockring

--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

My LBS put an XT rear derailleur and mtn bike cassette (12-34)on my Roubix.
(2005=9 speed)
I'm a beginner and needed the gearing real low (I live in the mountains)
works great

"Qui si parla Campagnolo" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

mike said:

Can I put a Mountain Derailer on a 10 spd Dura Ace STI with a FSA Compact
Double? And use a 9 speed 34T cassette?

I realize there are no 10 spd MTB derailers available, but could I make a
9
spd work?. Wouldn't I just have an extra click on the 10 speed STI
shifter

Thanks
Mike

The RD isn't 9s or 10s, the shifter is. You cannot use a 9s cogset with
10s shifters, the spacing is too different. Using a '9s' RD will not
give you 9s spacing, the shifter determines that.

The only way to use a 9s cogset, MTB style, is to use Campag 10s
shifters, a Campag long cage RD and then say a 11-34 shimano 9s cogset
and chain.