Fitting 11-32 teeth cassette onto a road bike

[TheDoctor]

Its all down to the hanger.

It works with some bikes only.

Mine (2010 giant Defy 2) was right on the limit with 32T but the 2012 Giant comes with a 30t as standard.

Lucky i have some cassettes laying about from mountain bikes.

For what its worth any issue just fit a deore rear mech.

I dont know why manufactures keep fitting different toothed cassettes, the 2010 defy was 25T, 2012 was 30T and 2013 is 28T

I live in a hilly area (The Blackdown Hills) so do like a bail out gear

2012 Shimano rear mechs will go up to 30T as standard. Older ones went up to 27T IIRC

 

[simmi]

Well I gave it a go today on by far the most extreme climbs I have ever ridden 14.5 miles with 2245ft of elevation.

It worked perfectly, a bit of a strange noise when dropping from 32T to 28T a bit like those cash registers you got in the old days.

 

[slowmotion]

The rules that Shimano give for which gear combinations will work are rumoured to be pretty conservative. You can usual go over by at least three teeth, they say. A long hanger on the rear mech. is certainly a bonus. My 105 mechs are 50,39,28 with 11-28 on the rear. That shouldn't work, but it does.

And yes, Tynan, I am a gay weedy legs. Sorry.

 

[Peteaud]

2012 Shimano rear mechs will go up to 30T as standard. Older ones went up to 27T IIRC

And to confirm that Spesh are fitting a 32T to their Roubaix.

Ive always taken the Shimano Tech as a guide only, but it also should mean a 2012 Mech will take 30T no problems on an older bike.

 

[fossyant]

What's all this mention of 30T and 32T cassettes on a road bike ? Never mind triple or compacts ?

 

[PpPete]

2012 Shimano rear mechs will go up to 30T as standard. Older ones went up to 27T IIRC

If you are lucky you can get an older 27T mech to cope with a 32T cassette. Mine will - and that's with an out of spec extra-wide triple (50-38-26) too.
That's seven extra teeth total beyond what Shimano reckon.
OK so it's on a tourer not a road bike, but you still all at liberty to point, laugh, call me names or whatever. I don't really care!

 

[lulubel]

If you are lucky you can get an older 27T mech to cope with a 32T cassette. Mine will - and that's with an out of spec extra-wide triple (50-38-26) too.

That triple is similar to what I have in mind for my bike when I set it up for touring (although I already have a MTB mech and 34T cassette). Did you get those chainring sizes by swapping the inner two on a standard road triple?

 

[e-rider]

I've done exactly this - 10 speed SRAM 11-32 cassette, with a Sora compact (!) and a 105 rear mech (!!)
There's no way on earth it should work, but it does

that must be a 105-5700 rear mech - the older 5600 con't cope with anything larger than a 27T sprocket

 

[TheDoctor]

No, it's 5600. It's only just coping with a 32T cassette, but I have a wide tolerance for that sort of thing...

 

[PpPete]

That triple is similar to what I have in mind for my bike when I set it up for touring (although I already have a MTB mech and 34T cassette). Did you get those chainring sizes by swapping the inner two on a standard road triple?

Sort of.
I happened to spot an ebay listing for a new 105 triple crankset and HT II BB, which lacked all but the 30T ring. It was from an LBS who seemed to have robbed the rings to sort an urgent problem on another bike, and then found it was not cost effective to replace them..... and, crucially, on the same day a well-known online retailer with a ludicrously cheap clearance sale on the 50 ring (always the most expensive).
Later I swopped the 30T for another ebay bargain 26T, so it was only the 38 I had to pay full price for.

Just about cost effective like that, but not otherwise. If I was doing it again I'd stick with square taper, and an Impact triple, or rather Spa's clone that they offer with a choice of rings. That's 110 BCD so it's a little more flexible in ring choices than a standard road triple at 130BCD, although the big ring might be a bit less rigid.