Wow, this is unexpected. I’ve just fitted a new GRX810 rear derailleur to a gravel frame. Looks and feels great, quite a substantial thing with a strong spring.

Only thing is, I can’t get the wheel out. Clutch is off. I’m running 42mm tyres and an 11-36 11 speed cassette. The cage just won’t pull back far enough to get the wheel out!

I had fitted the wheel before installing the mech, btw, or I would have spotted this earlier.

Try pulling it over towards the larger sprockets you pull it back as well. Either that or shift into the 36 sprocket and try.

Are you on 11sp sprocket when you remove?

Yeah, the geomtrie of the rear dropouts/derailleur hanger of the bike, combined with the geomtry pf the derailleur itself, somenintse makes it hard. I used to have to wrestle with the wheel on my old Epic, untill I I staled an Apex derailleur.

From that experience, I’d say:

Drop the chain of the front chainring. This gives more slack and room to pull the derailleur back.
Try shifting the derailleur to one of the larger cogs, but not the very biggest, they take up to much chain.
Then, really focus on pulling the cage AND pulled knuckle back and away from the wheel.

Thanks all. Matt- yes, I’m on the 11sp sprocket when trying this.

OK, temp (maybe?) fix.

I slackened off the derailleur mounting bolt, and rotated the derailleur mounting bracket about 45 degrees clockwise, so that its more or less horizontal. Its secure enough and I can’t see it moving.

Voila, wheel in and out with ease.

Ah, hold on, isn’t that how you’re supposed to mount it?

I think my GRX was similar, there were two protuberances on the hanger that looked as if they were supposed to sandwhich the dropout, but both are designed to be above the B-Tension tab, which forces the hanger mostly horizontal…

It’s possibly the way you’ve mounted the mech to the hanger, the first bit of the mount should poke out backward about 8 or 9 o’clock, and there’s a stop that lines it up. It’s different to what you might be used to, but once on properly its just as easy as a normal mech to remove the wheel…

Edit – as above, that’s the correct position

I had a similar problem with my old sram Rival group.

I had to rotate the wheel until the small indents in the 160mm disc allowed me to remove it, took a fair bit of head scratching to work that out when bike was new.

Replaced it recently with full GRX, problem has disappeared.

Ah, interesting- thanks all. On this frame (which is completely new to me), there’s an unusual ‘tooth’ protruding from the end of the hanger.

This slots perfectly into 2 smaller ‘teeth’ on the GRX mech, and indeed was so perfect a fit that I assumed thats the way it went. All sorted now.

Thanks oreetmon- I’ve seen something similar on SRAM.

That nearly caught me out with a Ultegra RX mech, too. Fitted exactly as if it was designed to fix around the hanger stop. Really not sure what that second protrusion on the mech is for.