Shimano GRX 12-speed (2023 GRX820/610)

50 days without a single post. I post a Little Update and get 7 off topic replies :thinking:.
Interesting mechanic

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Gotta get ready for all the sweet GRX Di2 11-speed firesales and take-offs that are about to happenā€¦ The people need to know how to make it awesome!!!

Iā€™ll probably grab that deore then, Iā€™d been looking 50t, but should have looked wider.

Do we think thereā€™s any way to run a 2* GRX with a dura ace 52/36 front and a larger than 36 rear using a separate cage or extender? Maybe an 11-40 xtr?

Trying to get the ultimate road / gravel one bike drivetrain for racing.

I tried SRAM 1*, 50 front 11-42 rear and needed more gears for flat TT sections or false flat descents. Also the shifting was dodgy and I could feel the cross chaining grind.

Frankly a 36 on the back would be great but I canā€™t find any 11sp 11-36 cassettes.

11-40 is meant to be doable in the 2x rear mech without even a hanger extender. By going to 52/36 youā€™re reducing your front capacity to 16 teeth compared to 17t on the 48/31 chainset so should probably work from a rear mech point of view. Might want a hanger extender or longer aftermarket pulley cage depending on your setup but there are enough stories of it working without either.
You probably want to use an ultegra or DA front mech with that chainset though - just so youā€™re in the sweet spot in terms of spacing. But that might reduce tyre clearance so that has to be considered.
It will be a very long chain though!

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I thought 11-40 seemed like a lot too but there are numerous reports of it working fine. And not just videos from a workshop, I know of at least one person that raced the GBDuro on that setup without issue and have seen (but canā€™t recall) other reports from hard usage in the wild.

Are you saying you used RX800 rear or front? The rear mech doesnā€™t care what size your chainrings are, only the difference between them. So 50/34 is the same as 52/36 (except for chain length of course). 53/39 is a smaller jump yet again. But from a RD point of view thereā€™s no difference between 56/40, 52/36, 50/34, 46/30, or 40/24 (even though the combos at the extreme ends of that donā€™t exist to my knowledge).

Yeah, my 50 - 42 was a full unbroken chain. At least that saved some thinking!

If only there was a 11sp 11-36ā€¦

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Ok, I should have said - that isnā€™t almost 400g and so way too heavy for racing.

Jack. Pot.

Or e.13 do a 9-39 and 9-34 11sp.

This is pushing it to the max. Garabuk 11-46 (11spd) and RD-RX817 (supposed to support 11-42) with a 2x up front. It sorta works, but not sure If Iā€™d race with it as the lowest gear 31/46 is really low for gravel and makes for some gear jumps that arenā€™t quite where Iā€™d like themā€¦

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With the FD? No, but 100% cannot run a road cassette and have smooth shifting across the range. So you have to run the cassette with the spacer. If I want to run an 11-32 or smaller I have to swap back to the RX815 rear mech.

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For reference, the SRAM 11-36 is like 30g heavier than the Ultegra 11-34, and 50g lighter than the XT 11-40ā€¦ So it falls right where youā€™d expect it to land for any of the larger manufacturers cassettes of this size. Itā€™s been my go to on my 2x GRX setup, paired with a 48/32 up front for any terrain.

Additionally I have ran a 11-40 out back, and the stock GRX derailleur handled it fine with the same chainrings. If youā€™re looking to go any larger in the cassette, youā€™d probably want to tighten up the front chainring spacing, by going 46/34 or something similar to that as youā€™re asking a lot of the derailleur in regards to take up.

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Yo guys, just please open another thread to discuss that. It is not relevant to the topic at hand.

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Itā€™s ok - there are some aftermarket options that work.

Honestly I donā€™t need more than a 1:1 gear ratio for any of the riding this bike would do, gravel or road. I just want a 1:1 at the rear with a 52 front.

The other option is to go 52/34 front and a light 11-34 rear. This obviously will create a chunk more chain slack and ruin the front shifting a bit, or 50/34 with a 9-36 rear but Iā€™ve never liked the super low small cogs and they are terrible for chain efficiency due to the articulation. 11 is a lot better.

Amen. Letā€™s keep this thread about the next GRX.

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What are the odds weā€™ll see anything before July?

Unbound perhaps?

Thatā€™s when I would launch it if it was my product! I think someone on the WW forum thread said they were told autumn though - so maybe Unbound launch and autumn availability? Or if it really is autumn for both launch and sales then perhaps theyā€™ll align with a major CX event? Even as iconic as Unbound has gotten, thereā€™s still more media coverage for CX at this point.

I think itā€™s likely to be factors like the megaphone of Unbound coupled with availability. OEMs first, then as group sets and separate components. Doing a big announcement and not having it on bikes people can buy is a paper launch that does nothing when it comes to sales momentum.

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I have delayed my race bike purchase for this release, any idea when should we expect availability?