Branson Gearing Choice

atasic

 Any input is welcome, so girls and guys don't hold back.

Branson course has 4700ft of climbing. It is either up or down. I run front 53/39 (Quarq mounted), compact is not an option. Last year ran rear 12-25. Had a good run after, but want to do better this year.

I plan on running 7900 11-27 rear with 7800 RD. Are there any issues with this. Anybody running this set up here? Shimano chart says no. Some bike shop techs, say ok.

What are your thoughts.

Thanks

atasic

Also would like to add a question, if 11-27 is not possible, if 12-27 is ok from the technical angle, would it be worth getting and running instead. Wondering how much of a difference does 11 make over 12 during descends.
Read the wiki, 12-27 is approved, also when in doubt more is better is it worth over 12-25.
Thanks

mgraffeo

I don't see why it wouldn't work, but haven't run it before. Personally, I'd go with the 12-27, because of the tighter gearing where I'd be spending most of my time. 53-11 ends up spinning out at a really high speed...

atasic

Thanks Mike, will look for 12-27 than. Was just thinking ahead for some courses down the road that have prolonged downhill sections where I could use 11. Thinking Vegas.....Not sure on that course. Hardly any other would need that 11 cog.