53/39 - Compact noticeably different

[stevenb]

Up and til yesterday when I owned my Felt I had a Compact chainset on it running a 11-23 on the rear.
I have ditched the bike I was going to buy (Focus Izalco Team 2008) for something a little more exotic.
Trouble is that the bike I like only comes in 53/39.
My mate said I would not hardly notice it...more so if I ran something like a 12 -25 on the rear.

What are your experiences of this?

Cheers all

Steve

 

[MichaelM]

I'd say 12-27 would be more what you're used to.

http://www.sheldonbrown.com/gears/

 

[Gary D]

This is just theory - not based upon experience!

But if you went for the double 53/39 and used a 12/25 cassette it would be like losing your lowest gear on your existing set up (assuming it is a 50/34 compact) and you would have a marginally lower top gear.

However, if you instead went for a 12/27 cassette, then it would be as near as damn it the same (in fact very slightly lower bottom gear).

If you go to Sheldon's Gear Calculator, you can put all the numbers in and see for yourself the effects of swapping components

http://sheldonbrown.com/gears/

Alternatively, could you ask the shop if they would swap the chainset for a compact if you wanted to stay with a compact?

Hope this helps.

Gary.

 

[Gary D]

MichaelM,

You beat me to it!!

You said in 1 line what took me 4 paragraphs

Gary.

 

[Crackle]

You might need to change the rear derailleur if you go 12-27.

 

[fossyant]

Just get fitter....hee hee hee......

I've only ever run 52/42 until last year when went to 53/39 and only have a 21 top on the back - and I live in the Peak District.....

You'll loose out on the climbing gears, why not start with a 13 and save one sprocket for the lower gear ?

 

[stevenb]

Cheers for your help guys.
The link is very useful.

I would prefer to keep my lower gear ration as I have often found myself in 1st gear on climbs (when I was using a compact with 11-23). So as long as I can keep the 1st gear ratios the same then I'm happy.
53/39 and 12/27 seems pretty good to me.

Ideally I'd like to keep the 53/39 as the bike Im looking at has a Dura Ace chainset.

 

[MichaelM]

What are you looking at instead of the Izalco?

 

[stevenb]

Result.
I have ordered my new bike with a Fulcrum RS hollow carbon crankset which is a compact and thus will compliment the Dura Ace nicely and allow me to stick with my preferd 11-23

 

[itisaboutthebike]

Both Campag and Shimano short cage will handle 27 tooth cogs (even tho Campag say 26 in thier blurb) with either 39/53 or 34/50. Mite need to run a slightly onger chain tho.