Support road.cc

Like this site? Help us to make it better.

Shimano 105 10-Speed Cassette

I'm looking to change the 12-25t cassette (Shimano 105/10spd) for a 11-28 cassette. Can anyone tell me if I will need to change the rear mech as well? I have a compact (50/34) chainring. Thanks.

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

Add new comment

7 comments

Avatar
SirCav | 9 years ago
0 likes

Thank you. v helpful.

Avatar
SPIKE718 | 9 years ago
0 likes

I changed my Ultegra 6770 from 11-28 to 12-30 yesterday. No adjustments. Works very well indeed.

Avatar
SirCav | 9 years ago
0 likes

Thanks all. Very helpful and much appreciated.

Avatar
LondonDynaslow | 9 years ago
0 likes

You won't. You may need to tighten the B-tension screw but probably not (mine is fully out with a 28t but screwed in a bit with 30t).

Avatar
shmooster | 9 years ago
0 likes

Even the original 5700SS derailler should be fine with a 28T cassette. If you go to 30T you'll need a 5701SS or a GS, and if you go to 32T you'll need a GS

Avatar
CXR94Di2 | 9 years ago
0 likes

I have a 32T on my rear cass. I only use it as my bale out gear when I am completely done in. It allows me to maintain a decent spin rate whilst hiding the fact I am knackered  1

Avatar
Ali Gibb | 9 years ago
0 likes

I changed my 11-25 to a 12-30 on compact 105 and its fine. Took a fair amount of fiddling and it really should have had a longer arm but I make sure I never use 30 when in the 34 cog, which isn't a problem.

Latest Comments