With my Ultegra equipped road bike, the chain touches the front derailleur when shifting to the two highest gears (high = smallest cassette rings, large front ring).
The adjustment considerations in the Shimano manual only have the cassette in the largest ring. Since that’s not my problem, I was wondering how to adjust the front derailleur so that I can use the two highest gears without the chain scraping on the chain guide.
This is the manual I was looking at: DM-RAFD001-02-ENG.pdf (shimano.com)
They’re counterintuitive if you’re used to older derailleurs where the H screw adjusts a hard stop, but follow the cable tension and top (H) adjustments as prescribed (maybe use 0 clearance for the Top adjustment) and it should work.
By 0 clearance you mean to make the chain guide actually touch (or almost touch) the chain when in top gear, right?
Sounds to me like high adjustment needs to go out a smidge.
No I mean when adjusted according to the instructions (big big combo, shifter in the top trim position) go for the 0 end of the 0-0.5 clearance range.
Gave it my best, but couldn’t get it to work properly. Either big-big or big-small touched the chain guide. There was just no way of making it work with both extremes. And it’s not just one ring in the cassette, but only the third or fourth that made the chain pass without touching the guide.
Might that have to do with cable tension being too low? I know it’s difficult (or rather impossible) to say without actually seeing the bike, but maybe someone with experience has a good guess on this?
If you’re making your adjustments without trimming the front d, you won’t be able to get it to not rub in big/big. You’d adjust the low side first, then shift into high trim and make your high side adjustments there since you’d have your front d trimmed any time you were actually in that gear.
Make it rub in big-big, to remind you that you shouldn’t be in that gear.
For the derailleur to be that much out of adjustment I’d suggest the mounting angle is off. But make sure to get your mounting height right too.
By chain guide you mean the derailleur cage right, and not an independent of the derailleur chain guide? (I know, asking about a chain guide when you have a derailleur… just want to make sure)