Cannot figure this one out can anyone help please?
Its a ultegra triple, 12 - 30 cassette and a long rear mech, top pjockey hits largest sprocket when it moves across and can not jump on board it
More B tension?
Chain length ?
B tension!
So long as the cassette is within the bounds of the mech (check on t'internet).
Bent or broken Mech Hanger
...or your mech has twisted round, which would probably be a symptom of the above
Don't Shimano cages now have the max cassette size on them. Top of hanger.
What they said tho. B screw.
which generation ultegra? bear in mind that long cage is about how much loose chain it can take up (forget the correct term) not about how big a sprocket it can accommodate. The ultegra on my bike states a max of 28 tooth sprocket.
EDIT: what was said above about B tension may well do enough to make it work - sometimes the stated range is conservative
Must be getting too old, yes it was the B tension, it was screwed in all the way so backed it off until they were not touching, all sweet now.
It was the ultegra 12 - 30 (6700) cassette so I assumed it would be safe however looks like the 6600 rear mech is max 27t, however look's ok at the moment.
Not touching and changing on the rear ok, needs a bit more tweaking for the front or would I have made it impossible to get the front right with what I did?
Anyone care to say if anything bad is likely to happen or can I just suck it and see?
Why am I doing it - for a trip round the lakes needed some low gearing
I was experimenting with this myself because I was scared of Winnats Pass. I couldn't get it to work properly but I think this was down to a not quite straight mech hanger as lots of other people have got it working. I might try again now I've had the hanger straightened. The people who did get it working suggested that shifting at the extremes of the cassette might not be quite as smooth as with a narrower range cassette.
In the end I got up Winnats with a 12-28 though I'm now considering my options for the Ventoux next month (mtb cassette and rear mech are looking rather attractive).
What shimano are doing making an ultegra cassette which doesn't (according to them) work with any ultegra mechs I don't know 🙄