Upgrading 11/25 > 12-28 cassette ?

LeWidget Posts: 2
edited August 2015 in Workshop
Hey guys,

I need to replace some parts on my bike, but was hoping for some advice.

The chain Im planning on getting is,

KMC X10-73 114 links

But I was advised that, as my current chain was really flexable, I should consider replacing my Cassette too.

Currently I have an 11/25 Shimano 105 5600 , but would like to go to a 12/28t. I've been told, however, that Im limited to the size I can go as a result of my chainrings and my derailleur size (SS short cage)

2x Chainrings - 52/38
cassette - have 12/25 - want 12/28 (maybe 11/28)

***Question: 11t is a harder gear then 12t ? So if I wanted my hard gear to be a little harder, and my eaasier gear to be a little easier.. I should change from 12/25 to maybe 11/27 or 28???

subtract small chainring teeth from big chainring + subtract smallest cog from largest) total number needs to be 29 or less. )) total comes to 27.

Am I limited to a max of 27t on my large cassette ring? Has anyone gone 28t with this setup before ?


  • First.Aspect
    First.Aspect Posts: 15,944
    I think 28T is the maximum for a short cage rear derailleur, so you should be okay.

    An 11T on the cassette is a longer gear (i.e. harder to pedal) than a 12T.

    The advantage of a 12-28 is a closer spread of gear ratios. Disadvantage is that you compromise your longest gear, and you might "spin out" going down hill. With a 52T up front, I doubt you really need an 11T, because you'll still be able to pedal up to 40+mph.

    The only time you need to worry about the difference between number of teeth is on the front chainrings. I think something around a 16T difference is what most of the manufacturers will say that their front derailleurs will cope with.