Road mechs on mtbs

[24pouces]

I usually use road mecht on my MTB : mavic on my Merlin, campy on my klein attitude, ( and if possible, small cage mecht.)
I prefer the design, the esthetic, and the clearence too.
I use 32t cogs with them. Yes, it's big, but I change the spring for a stronger and they work fine. (On the campy derailleur, it's an old chorus whith 2 position, A and B. With the B position, the parallelogram could go on very big cogs.)

I agree with andrewl : short cage mtb seems to be "medium" in road. On my heihei, I tried with a DuraAce 7400, but I had some problem. So, I changed for a XT with small cage and the shifting is more sure and confortable.

On rear suspension bike : it's a long cage for the c'dale EST (the cage work a lot with the swingarm) but, on the RS1, it's a campy road deraillleur and still now, I don't have problems.

The main thing iportant is to shift with care and to not cross the chain (small ring and small cog, or big ring and big cog…)

 

[We_are_Stevo]

Does chain length actually have anything to do with it?

It's the difference in length between the extremes. On a trad MTB it'd have to accommodate everything between 46/28 (tight chain) and 24/12 (baggy chain). That's a bigger difference than between 52/25 and 39/13 or whatever on a road bike. Longer cage takes up more slack.

Perhaps, as 24pouces already mentioned, it's because I only ever go halfway across the cassette on the outside/granny rings that I've never had any issues with a slack/tight chain??

I only use the full range on the middle ring - probably why I don't break anything despite being on the lardy side of svelte too

 

[Tazio]

Perhaps, as 24pouces already mentioned, it's because I only ever go halfway across the cassette on the outside/granny rings that I've never had any issues with a slack/tight chain??

I only use the full range on the middle ring - probably why I don't break anything despite being on the lardy side of svelte too

Of course strictly speaking if you are on the big ring or the granny you should only use the top or bottom few gears at the back or your chainline will be all over the place. A bit different at the middle ring where you should get everything without a struggle.

 

[bm0p700f]

I use one but as tensionor on a single speed. No shifting problems there.

 

[MikeD]

it's because I only ever go halfway across the cassette on the outside/granny rings that I've never had any issues with a slack/tight chain??

I expect you could get into the "nasty" gears if you tried, though. Using a really short mech on a trad triple-ring setup pretty much requires that you ride as you do (which is eminently sensible), which is why it works most of the time. I tend to use bottom three sprockets in granny, most of the cassette (usually except the top couple) in middle and the top half in big ring, but I have enough chain wrap to go into big/big because sometimes I forget what I'm doing

 

[legrandefromage]

been there too and also do mech mixing:

 

[WD Pro]

Had a short 735 on the Marin since about 91, this being the second :

It's on road ratios now but when it was on a 12-28 it was set up safe i.e. A bit to slack on small / small rather than oh sh1t, why did I shift onto big / big

WD

 

[oldave]

Certainly matched a short rear mech with a single ring up front on winter bikes in the past. Works fine with 9 speed as far as I recall.

 

[Barneyballbags]

I ran short cage 105 and Ultegra mechs on all of my Dual bikes without a problem. I also ran road mechs on some of my DH bikes with no issues.

I'm not sure what they would have been like with a regular MTB cassette and triple chainset up front, but they certainly did the job that I needed them to do just fine

 

[Piers]

I ran short cage XT with a 12-28 cassette and MTB rings. No problems and I miss having the clearance on my modern bikes.