Use Compact Crank with 9-Speed Group

[johnkjos]

Hi all,

I'd like to convert my 9-speed Campy Record bike (it's a Colorado Ti in perfect condition) from a triple crank to a compact crank set-up. All compact cranks that I have seen are for 10 or 11 speed groups. Will these cranks work properly with a 9-speed group? I use a Record 9-speed chain if that makes a difference.

Thanks,

John Kjos

[thwart]

John-

Have no fear. I have an FSA Carbon compact, a Campagnolo Veloce CT compact, and a Campagnolo Centaur UT compact on 9 speed bikes and they work great---no issues at all.

[johnkjos]

Thanks "thwart". Your input is much appreciated. From the sound of it there is no rubbing due to the slightly wider chain width. Right?

[thwart]

Never an issue. The chain width difference is not that great, and shifting performance is very similar to my 10 spd set-ups.

Before you spring for a compact specific FD, try the double (or triple) FD you have now. It'll likely work better than you think. Of course, you'll have to adjust it downward a bit for the smaller big chainring...

[sean]

I did something similar recently with an indexed Suntour Superbe Pro 7sp group. Yes, 7sp, no laughing.

The only issue was swapping out the FD as well to handle the compact. Works pretty damn good other than a little trimming now and then to keep the chain from rubbing on the front.

[jmeloy]

set up right it works very very well

[endosch2]

I have a CX bike with 9 speed set up with a 10S Centuar crank / UT BB - it works fine - no prob!

[Ken Robb]

my Hampsten has 9 speed Campy w/50/34 Ritchey Octa-link crank and it works perfectly.

[DHallerman]

Never an issue. The chain width difference is not that great, and shifting performance is very similar to my 10 spd set-ups.

Before you spring for a compact specific FD, try the double (or triple) FD you have now. It'll likely work better than you think. Of course, you'll have to adjust it downward a bit for the smaller big chainring...

Some of my best from shifting with a compact setup -- 48/34 tooth -- and a nine-speed rear has been with an older FD, a Dura-Ace 7410.

What was that, the eight-speed era model?

But besides the OP -- who is using Campy -- wouldn't Shimano STI shifters be fussier about the FD than Campy Ergo?

Dave, who has several bikes with 48/34 chainrings and Campy shifters and finds significant variation in how well the different front derailleurs shift

[Ken Robb]

my Rambouillet has 9spd Ultegra triple and it index shifts perfectly at both ends. I had a DA 9spd triple on another bike that also shifted perfectly with DA triple cranks but required a 1/2 click trim when shifting a 48-38-28 TA Zephyr crank. It was no big deal but I think the Campy front shifters are easier for a mix/match set-up because they are essentially friction with fine detents.

[vqdriver]

i guess i'll chime in. i ran a 10sp compact and 9sp chain. worked very well in all combos except in the small/small when the chain would catch on the shift pins on the large ring. not addressable with trim. but not really a big deal anyway.

as mentioned in previous threads tho, this seems to not be the norm and may also vary with chainline and chainstay length. but it can happen.

[John M]

i guess i'll chime in. i ran a 10sp compact and 9sp chain. worked very well in all combos except in the small/small when the chain would catch on the shift pins on the large ring. not addressable with trim. but not really a big deal anyway.

This happens on lots of 10s set ups even with a 10s chain, especially on bikes with short chainstays.

Since nobody actually rides in the small/small combination anyway, it is a moot point, right?

[dawgie]

I am using a Campy Centaur 10-speed compact crank on a bike with a 9-speed Dura-Ace and Ultegra group, including the chain. It shifts flawlessly.

[thwart]

This happens on lots of 10s set ups even with a 10s chain, especially on bikes with short chainstays. Since nobody actually rides in the small/small combination anyway, it is a moot point, right? Yep. This is a result of a 16 (or sometimes 14) tooth difference in size between the large and small chainring. This same difference in chainring size means FD shifting won't be quite as seamless as your triple, with only 10 or 12 tooth differences between rings. It also means a somewhat higher risk of a dropped chain with downshifts from the big to little chainring. I use a chaindrop preventing device on the compact crank bikes that get used in group rides.

In my experience these issues are not significantly different between 9 and 10 speed setups.