shimano grx

Especially for light weight issues concerning cyclocross / touring bikes & parts.

Moderator: Moderator Team

User avatar
ultimobici
in the industry
Posts: 3547
Joined: Sun Nov 21, 2004 2:45 pm
Location: London, UK
Contact:

by ultimobici

Shimano have all of the information regarding compatibility on their website


https://productinfo.shimano.com/#/com?c ... acid=C-450


Sent from my iPhone using Tapatalk

by Weenie


User avatar
FIJIGabe
Posts: 2019
Joined: Tue Sep 11, 2012 6:07 pm
Location: The Lone Star State

by FIJIGabe

Does anyone know the availability of this groupset for commercial sale? I know some bikes are starting to come with the group, but none of the traditional retailers have started selling it as a groupset (some have individual parts, but at astronomical prices).

Bcoxa
Posts: 36
Joined: Fri May 26, 2017 8:44 pm

by Bcoxa

Depends where you are I suppose, bike24 in Germany has it as groupset. Sigma in the UK has some competitive prices on individual parts

User avatar
FIJIGabe
Posts: 2019
Joined: Tue Sep 11, 2012 6:07 pm
Location: The Lone Star State

by FIJIGabe

Good to know. I guess it's too early to expect any deals on the parts, at this point. I'll hold off for a bit until I decide whether to upgrade my current bike, or just buy a new one (avoiding the issue of having to run post-mount to flat-mount adapters).

User avatar
ultimobici
in the industry
Posts: 3547
Joined: Sun Nov 21, 2004 2:45 pm
Location: London, UK
Contact:

by ultimobici

Anyone know how an XTR Di2 front mech is on an GRX double?

Wondering if I can use a GRX crank with my existing XTR setup


Sent from my iPhone using Tapatalk

ooo
Posts: 971
Joined: Sat May 21, 2016 12:59 pm

by ooo

May be you will have more success with 46-32 chainrings from Metrea FC-U5000-2 (asymmetric 4x96 bcd)?

XTR 2x11 FD cage is optimized for 10T difference:
test link: FD-M9070 + 48-34t = it looks like cage is on the limit, and it will be too short for 48-31 or 46-30

I think it is possible to install longer triple cage from FD-M9050 on double FD-M9070
I have both FD-M9050/FD-M9070, but I need cage tool TL-FDM905 to test cage swap

Image
'

User avatar
ultimobici
in the industry
Posts: 3547
Joined: Sun Nov 21, 2004 2:45 pm
Location: London, UK
Contact:

by ultimobici

Looks like I’ll be better off sticking with the 44/30 I’m running and use a 10-42 cassette.

Thanks


Sent from my iPhone using Tapatalk

6un4
Posts: 15
Joined: Thu Apr 09, 2020 10:39 am
Location: Lithuania

by 6un4

Bought part of grx group last November. It's ultegra hydro levers + grx rear mech + xt 11-42 cassette. All together works very well and I'm really Happy with outcome. Haven't dropped chain yet ( praxis zayante with 42T ring ) cable pull ratio is the same, so no problems at all.

tomh79
Posts: 170
Joined: Thu Dec 27, 2018 9:50 pm
Location: Switzerland

by tomh79

I'm thinking of buying the 48/31 crank. Currently use a FSA 46/30. Since I'm riding a lot of pavement with this bike I often spin out on 46/11 - I think 48/31 would be perfect for road and gravel. But: The q-factor is 5mm wider (151mm vs 146mm on normal road cranks) - I've never used a wider crankset...is this something you're going to notice?

jmfreeman535
Posts: 269
Joined: Wed Sep 18, 2019 8:12 pm

by jmfreeman535

tomh79 wrote:
Wed May 06, 2020 8:43 pm
I'm thinking of buying the 48/31 crank. Currently use a FSA 46/30. Since I'm riding a lot of pavement with this bike I often spin out on 46/11 - I think 48/31 would be perfect for road and gravel. But: The q-factor is 5mm wider (151mm vs 146mm on normal road cranks) - I've never used a wider crankset...is this something you're going to notice?
I definitely noticed it, and it was causing quite a bit of pain in my hips and knees. I ending up swaping out the GRX groupset for Ultegra Di2 (and shorter spindle pedals), just to get the normal q-factor. Problem solved

With that said, I've always been very sensitive to small changes, so it may not be an issue for you. If you don't notice a difference between road and mtb pedals, q-factor wise, then you probably won't notice it at the crank.

tomh79
Posts: 170
Joined: Thu Dec 27, 2018 9:50 pm
Location: Switzerland

by tomh79

jmfreeman535 wrote:
Thu May 07, 2020 6:40 am
I definitely noticed it, and it was causing quite a bit of pain in my hips and knees. I ending up swaping out the GRX groupset for Ultegra Di2 (and shorter spindle pedals), just to get the normal q-factor. Problem solved

With that said, I've always been very sensitive to small changes, so it may not be an issue for you. If you don't notice a difference between road and mtb pedals, q-factor wise, then you probably won't notice it at the crank.
Thanks for the feedback. Not sure - I really like 48/31 - but maybe I will end up buying an Ultegra crank as well. Or buy the GRX and then sell it maybe...

User avatar
kytyree
Posts: 761
Joined: Thu Oct 09, 2008 4:55 am
Location: US

by kytyree

I like the 48/31, obviously you notice not having a taller big ring if you're somewhere you can wind it out on the pavement for a bit but I think overall it's well suited to a gravel bike. If I was building an all-road, where the expected use was closer to 50/50 pavement vs dirt I'd probably go bigger.

I've not had any trouble with the q-factor on my gravel bike. But I rode it all winter whenever I could get out, and what I definitely noticed when I got the road bike back out this spring was how narrow it was. A few rides later I'd forgotten about it but the difference is there.

tomh79
Posts: 170
Joined: Thu Dec 27, 2018 9:50 pm
Location: Switzerland

by tomh79

kytyree wrote:
Thu May 07, 2020 2:50 pm
I like the 48/31, obviously you notice not having a taller big ring if you're somewhere you can wind it out on the pavement for a bit but I think overall it's well suited to a gravel bike. If I was building an all-road, where the expected use was closer to 50/50 pavement vs dirt I'd probably go bigger.

I've not had any trouble with the q-factor on my gravel bike. But I rode it all winter whenever I could get out, and what I definitely noticed when I got the road bike back out this spring was how narrow it was. A few rides later I'd forgotten about it but the difference is there.
Thanks! I currently ride my road crank with the cleats at the widest possible position - so I could probably adapt with the cleats. I think I could shift at least 1-2mm on each side. I really like that 30 or 31 cog in the front...if it wasn't for that - I would have bought the Ultegra 50/34 long time ago. Of course I could also switch to a 11-36 or 11-40 cassette but..not sure if that's what I want..

jmfreeman535
Posts: 269
Joined: Wed Sep 18, 2019 8:12 pm

by jmfreeman535

tomh79 wrote:
Thu May 07, 2020 4:07 pm
Thanks! I currently ride my road crank with the cleats at the widest possible position - so I could probably adapt with the cleats. I think I could shift at least 1-2mm on each side. I really like that 30 or 31 cog in the front...if it wasn't for that - I would have bought the Ultegra 50/34 long time ago. Of course I could also switch to a 11-36 or 11-40 cassette but..not sure if that's what I want..
If you have a wide set up on your road cleats, then I'm sure you would be fine with q-factor of the GRX crank. Another think to keep in mind, though, is that you'll need to use the GRX front derailleur, with the crank, due to the different offset in chainline.

tomh79
Posts: 170
Joined: Thu Dec 27, 2018 9:50 pm
Location: Switzerland

by tomh79

jmfreeman535 wrote:
Thu May 07, 2020 6:07 pm
Another think to keep in mind, though, is that you'll need to use the GRX front derailleur, with the crank, due to the different offset in chainline.
True! But then - I've read in this forum (I think) that several people got it working with the 105 FD?! Not sure if I should try first and then order the GRX FD...or just send it back...

by Weenie


Post Reply