Rear Derailleur Fitting

[Boab]

So... Fitted the new rear mech, a RD-RX812 1x11s GRX, exactly what I had on the bike before. I had no issues with fitting last time around, this time I can't get the bleeding thing low enough to not foul on the rear stay, or get into the top three rings. I didn't need an extra long B-screw last time, so I don't know why I'd need one this time. The thing is correct up against the B-tension stop and I've taken so much slack out of the cable it wont shift down into the bottom two cogs.

What am I missing here...?



I've also checked, as far as I can, against the bits I took off and they all look the same...

[AlexGold]

Looks like you might have fitted it wrong - it's meant to stick out backwards nearly 90 degrees from the hanger. There are two prongs on the mech, you'd think the hanger goes between them like I assumed first time I saw one, it actually goes against the lower one. Page 8 here where it says 'stopper plate' shows what I'm on about: https://si.shimano.com/api/publish/stor ... 02-ENG.pdf

Hopefully it's as easy as that and I'm not looking at it wrong!

[redefined_cycles]

Bob... I don't ride GRX but it looks to me just similar in design to a standard rear shadow mech. I'm guessing you've accidently goy the tab behind the mech at the wrongOclock position. Should look more like this (pic1) so the tqb behind on the mech rests against the mech hanger tab from the top pushing down (pic2)

[redefined_cycles]

Pic1


My finger be resting on thw tab of the mech that pushes down and sits flush with the mech hanger from the top...

Just like what Alex said I think...

[Boab]

Spot on chaps.

I had the wrong tab bit butted up against the stop, FFS!!! Been staring at that f'ing PDF all afternoon trying to figure out what I was doing wrong...