Scottyoz

Hi all,

i am wanting to run a 34 tooth cog for some audax rides i am doing next year. I currently run a 34-45 compacts with a 14-28 ten spped cassette. Due to the size of the 34 what sort of rear derilleur do i need to run such a cog? My set up is campag chorus ten speed.

Campag state that they only go up to 29 teeth but can this stretch to 34 or 32 so long as the chain angles are not bad? Or can a suitable Shimano rear derailluer be used. Yes i know Campag and Shimano dont mix but i have used both brands together before and although the mix isnt perfect in most cases they do work.

Thanks for you help...

HillRider

Campy rear derailleurs probably won't clear a 34T cog even with the b-screw all the way to the most rearward setting. You would have to use a Shimano (or SRAM) MTB rear derailleur. If you can't get it to shift well over the Campy cassette with the Chorus Ergos, Jtek's Shiftmate will dial out the differences.

BTW, Shimano road rear derailleurs are rated for 27T max and will really clear a 30 and sometimes a 32 but almost never a 34T so you need an MTB rd to work.

Scottyoz

Cheers Hillrider, thanks for the direction