Where have I gone wrong?

[thefensman]

Hi folks, have just fitted a new inner 39t chain ring in place of a 42 and a new cassette, 11-32 in place of a 12-25. My groupset is all Tiagra and rear derailleur is medium cage. Problem is after setup I can engage all gears except largest rear/large front, is this to be expected due to extra teeth on big cog or am I missing something. Any help will be appreciated, Forgot to add large chain ring is 52.

 

[numbnuts]

I think with the 11-32 you need a long cage

 

[User269]

Off the top of my head I can't remember if your configuration is compatible with your rear mech, but assuming it is, using the biggest sprocket and largest chainring isn't a good idea due to the severe angle the chain would be at. Common advice suggests this should be avoided, although such a gear can normally be selected.
I don't know what adjustments you've attempted so far, but I also wonder if you need a longer rear mech, as numbnuts has just suggested.

 

[RebornBumbler]

Is the chain long enough to go round 52/32 and through the rear derailleur ?

 

[User6179]

Hi folks, have just fitted a new inner 39t chain ring in place of a 42 and a new cassette, 11-32 in place of a 12-25. My groupset is all Tiagra and rear derailleur is medium cage. Problem is after setup I can engage all gears except largest rear/large front, is this to be expected due to extra teeth on big cog or am I missing something. Any help will be appreciated, Forgot to add large chain ring is 52.

Did you not change the chain ?

 

[screenman]

Doh! Sounds like chain lengthy.

 

[thefensman]

Thanks for replys folks, I haven,t replaced chain as it was only fitted around 900 miles ago, but it never occoured to me that I would need more length due to extra teeth on big cog. Will probly have to invest a few more pennys.

 

[thefensman]

Have just checked my chain and link count is 108 so a new chain which I think comes with 114 links could be the answer and as whiskeywheels states I do understand that big/big combo isnt good due to poor chain line.

 

[youngoldbloke]

Just two links may be enough. 52 x 32 entered into the Chain Link Calculator I use gave 55 inches = 110 links. (You can't add just 1 link BTW, 1" = 2 links, an outer link and an inner link)

 

[thefensman]

Thanks youngoldbloke, i,ll have a route around in my bits bin and see if I can find links. I,m pretty sure I removed links when I fitted the chain when new.

 

[Drago]

With a thousand miles on it the chains well on its.way to the bin anyway.

 

[Cycleops]

I think with the 11-32 you need a long cage

The med cage should be fine. I am using one with a 32t.

 

[Onyer]

For my Ultegra with a 52/36 and 11-32 combination I had to buy the long cage. But then they only offered short or long cage options.

 

[Cycleops]

For my Ultegra with a 52/36 and 11-32 combination I had to buy the long cage. But then they only offered short or long cage options.

That's odd as Shimano only offer a long or short cage according to online retailers. Long cage are mostly available on MTB type mechs. I think you must have a med, which will work fine.

 

[Onyer]

That's odd as Shimano only offer a long or short cage according to online retailers. Long cage are mostly available on MTB type mechs. I think you must have a med, which will work fine.

Quite right, short cage and medium cage. Apologies if I have mislead anyone. I knew that I had to have the longer one of the two.