Double to Compact

TheBlaaMan

Quick question: is it possible to change the inner chainring on a Shimano Double from 39t to 34t?
I imagine that this is easier on the top end chainsets - Dura-Ace, Ultegra etc; but what about the chainsets lower in the Shimano stable.

Its a hypothetical question at the moment, about a bike I may buy, and I'm not sure what chainset is installed, but think its a 2300.

clog

Dont think you can do it the spacing on the chainrings is 130mm on a standard double but i think its 110mm on a compact

victorcarrera

38t is the smallest you can get for 130mm BCD so it wouldn't be worth your while. Compact or different ratio cassette might be suitable.

full gas

34 ,52 , will not work to much of a jump for chain ,

AstraMonti

You can do it. There is a specific brand of chainrings (which I can not remember now, I ll come back later with it) that have compact chainrings on 130BCD but they are probably twice the price of a whole 2300chainset

Quigs Snr

Not worth trying to do. Better off just buy a cheap Sora compact on Ribble for about 40 euro ex delivery.

doozerie

Don't forget to check that your rear derailleur can handle the new gearing range too, should you change to a compact chainset. In the worst case you may have to replace it too. I don't know if compact chainsets pose problems for "regular" front derailleurs but that's something else to check.

TheBlaaMan

Great,many thanks for the info guys,
B