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Jensen had some GRX stuff on their website recently and I preordered the GRX cranks almost a month ago. They haven’t shipped yet and still says shipping in “2-3 weeks.”

Anyone have any GRX stuff in hand? Curious about availability timeline.


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Jensen had some GRX stuff on their website recently and I preordered the GRX cranks almost a month ago. They haven't shipped yet and still says shipping in "2-3 weeks."

Anyone have any GRX stuff in hand? Curious about availability timeline.

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Got my GRX rear derailleur RD-RX810 today from ebay, it is a little bigger that RX800, 10g heavier but shares common parts.



 

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Where did you get that, I've been bugging the Brazilian Shimano importer for some more info on the GRX stuff and I'll I got was, it's coming soon.
Search on ebay (two or 3 sellers) and aliexpress (one seller), the stuff is original, not fake. Di2 version is not there for the levers, but RX812 RD should be there I believe.
 

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I just got a GRX 46/30T crankset (Universal cycle) and put it on. (I pulled off a White Industries 46/30T crankset with a square taper bottom bracket).

I've got about 70 miles and 8000ft of climbing on it so far, and I am quite pleased. The crankset I got is claimed to be at the 105 level, but the only differences between it and the ultegra level GRX crankset is it is 46/30T rather than 48/31T, and weighs in about 80 grams more (and the same as my WI crankset + steel square taper spindle). Oh, and it costs significantly less.

My GRX crankset (and Ultegra bottom bracket) are at least as smooth shifting as the WI crankset it replaced (which in turn had previously replaced an Ultegra 50/34T), when the WI crankset was new (now it is a bit beaten up). I am using it with a Di2 drivetrain, including an 11-34T cassette. It works fine on all of the gears, including cross-chaining. One thing to note is that I had to crank the H limit screw to its outermost limit in order to get it to work with the current Ultegra Di2 front derailleur (mine is a clamp-on). If you can't move your H-limit out another 4mm, this probably won't work with your current derailleur.

The chain-line and Q-factor are wider, so consider this carefully.

The main advantage of my WI crank is it had a narrower chain-line. (Also you can easily change the cogs and many sizes are available, plus it is blingy, over-priced, boutique, and made in the USA. It is also square taper, although WI makes three versions of a new one with 30mm spindles). If you can live with a bit of a wider chain-line and Q-factor, this is a vastly more cost-effective option.
 

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Hi everyone. I received and installed GRX on my Cannondale Topstone yesterday. Setup:
- GRX ST 600 shifters, RX400 brakes
- FC RX600 1x Crankset, 40T
- RX812 long cage RD
- CS-M8000 11-42 cassette
- HG701 chain

Not too many miles on it obviously, but one issue is very clear - chainline is too wide. The chain is levelled at 7th speed on the cassette, which means that the chain twists significantly when you switch to the largest cogs.
And of course there is this "backpedal issue" - when you try to backpedalwhile on the largest cogs, the chain just falls off to the smaller cog.

Any decent workarounds? Shims between the crankset and chainring? Maybe try SRAM cassette? (PG1130)
 

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The SRAM and Shimano Cassettes are interchangeable, so I don't think that will solve your problem.

Don't backpedal while on the largest cog?

I rented a (SRAM) 1X for 24 hours once, and it had the same twisting chain issue. I thought that was an inherent characteristic/limitation of the 1X (which necessitates the larger cassette cogs, and doesn't have the more in-bound small chainring).

My 2X GRX crankset, with the otherwise Ultegra 6800 Di2 groupset and 11-36T SRAM cassette can cross-chain big-big without issue, FWIW.

Do you still have your previous crank from the Topstone? I would put that back on and see if it resolves your issue.
 

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I think the combination of a larger chain-ring and the chain-line is probably making it worse.

Do you need the larger chain-line? Maybe a 1X crank with a smaller chain-line would solve the problem. (I don't know what the 1X crank looks like, so I can't say shimming it would be straightforward, but you could try that as an experiment. I personally would hate that and worry about the structural integrity of the crank.)
 

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Hi everyone. I received and installed GRX on my Cannondale Topstone yesterday. Setup:
- GRX ST 600 shifters, RX400 brakes
- FC RX600 1x Crankset, 40T
- RX812 long cage RD
- CS-M8000 11-42 cassette
- HG701 chain

Not too many miles on it obviously, but one issue is very clear - chainline is too wide. The chain is levelled at 7th speed on the cassette, which means that the chain twists significantly when you switch to the largest cogs.
And of course there is this "backpedal issue" - when you try to backpedalwhile on the largest cogs, the chain just falls off to the smaller cog.

Any decent workarounds? Shims between the crankset and chainring? Maybe try SRAM cassette? (PG1130)
Change chainring to boost or eagle spec (if available for your crank). One of those will get your chain line spot on.

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Any suggestions on the 1x 40T crankset alternative for BSA bb?
Praxis Zayante 30mm
https://praxiscycles.com/product/zayante/

White Industries R30mm with TSR chainring -- pick whatever # teeth suits you
https://www.whiteind.com/tsr
https://www.whiteind.com/mr-30

These will fit in a BSA BB shell (with appropriate BB) as long as you don't have a Di2 wire in there.

There are probably loads of additional options.

Still, I wouldn't fix it until (a) you know what you have is indeed broken, and (b) you know that narrowing the chain-line will indeed make a significant improvement.

I'm not sure why @kiwim5 recommended a boost crank, as that would widen the chainline further. Maybe I am missing something.
 

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really dumb question but is the chainring mounted on the inside or outside of the spider? If your working with a 135mm spaced frame ive found this and rearranging the BB spacers improves chainline.
 

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Thanks, everyone. After putting some miles into the GRX, I can say that this is not an issue:

a) It turns out that 90% of the time I use gears 3-10, so having my chainline centered at gear 7 is more or less the center of my most used part of the cassette.
b) Backpedaling issue occurs on the largest cog only and when pedaling for more than 1 crank revolution, which I actually never do. I tried some tough technical climbs, most backpedalling I ever do is limited to half of crank revolution, which does not drop the chain.

Still it's a questionable design from Shimano. I can understand this chainline widening for 2x systems, but the logic of having the same chainline offest for 1x evades me.
 
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