Training & Nutrition - gearing change

i want to change my gearing, right now i am using a 53/39 front, with a 11/23 cassette. should i go with a compact in the front or change the cassette to a 12/27?

Geese you are pushing a 39/23 up steep hills??

I would go with the 12/27 if I were you.

Not only would it be way easier of a switch out a cassette (not removing the crank, cassette's take me <5 min to switch out) I think depending on how long you have been riding this combo you probably would find a compact too easy on climbs.

Post this in the road bike forum....

It's easier and cheaper to change the gearing in the rear.

Going to larger gears in the rear adds rotating weight, whereas going to smaller in the front reduces (component quality levels otherwise being equal).

That said, I don't like compacts because for my fitness and style of riding, and that of many others' I've observed, compacts leave you cross chained a lot of the time and lead to more double shifting. I think compacts may turn out to be a fad. But I don't know anything about you and how you ride to advise, except to go to the Sheldon Brown gear calculator and play around with it.

I think compacts may turn out to be a fad.

Unlikely

thanks for the replies, i have it down to either a 12/25 or 12/27. now with that said, right now i am running a 9 speed, ive gone to a couple of shop, velo, and colorado cyclery in pasadena. they recommend putting a 12/25, or jumping to a 10 speed cassette, and putting on a 12/27, leaving the 39/53alone. i will be buy a new cassette and chain on next friday. so............... 12/25 or 12/27? im leaning towards the 12/25, but by jumping to the 10 speed, i gain the 16t.hmmmmm, think typing.

We don't know how strong a rider you are and what kind of terrain you encounter. If it was me, with a 39 up front, I'd definitely go for the 27 and I'd also stick with 9 speed until the time came when I needed to do a major overhaul. One of my bikes has 12-28 on 8-speed and I never feel like I'm missing any in-between gears. But I don't know what'd be best for you.

10 spd is different chain width, cog spacing, and shifter movement...
so generally speaking, a 9 spd rig conversion needs new 10 spd shifters (for sure), 10spd chain and 10spd cassette
then
some cranks are both 9 & 10 compatible, and many rear derailleurs are also compatible, many 9 spd FDs can also be used, but not all... and given that each will have its issues, that means the sum will be an ill-shiftin mess.
which, of course, means an entire drivetrain switch.

but no doubt, 10 spd does allow you to keep some gears you might otherwise lose in a wider range 9 spd cog set.

if i go with the 12/27, will the ultegra derailleur handle it?

Yes, the Ultegra will handle it. I made this swap myself.

Well doesn't that depend on you. If you routinely use a 53X11 or a 53X12, no stay with what you have. If you use your biggest gears very rarely and you would like lower gears for climbing, well then a compact would serve you very well indeed. Of course, changing to a compact cost $$$ while swapping out the cassette merely costs $. So that may be a consideration also.

i only use the 53/11 on the downhill side of climbs, i am going to try a 12/27 and see how it goes.

Go with the 12/27. It's kind of annoying to race on, because it makes for 'holes' in your gear stack at typical crit race speeds. Having said that, it's a good cassette to ride alone on. It covers a really big range of speeds and with the 27 out back, you should be able to climb really steep hills. I've got a hill I do that's around 22%, and a 39-27 combo is enough to climb it.

Having or not having an '11' is not at all an issue when you're alone, and is a minor deal when racing unless you're super fast and spend a lot of time over 40 mph (i.e. a pro).