GRX vs Ultegra 12 Speed

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CampagYOLO
Posts: 705
Joined: Thu May 06, 2021 3:58 pm

by CampagYOLO

Tifosiphil wrote:
Tue May 17, 2022 9:22 am
Going to ask a slightly off topic question in here as we have a lot of knowledge.

Running current generation GRX 810 with 11-34 rear and 52/36 front at the moment but have an everesting coming up in July. Been running this combo find in training but want a couple of spare gears on the day. Can anyone seen any potential issues with me sticking an 11-40 cassette on the rear and staying to just the inner chainring. 6 more than Shimano recommends but I've heard a lot of reports of it working. I won't be in the big chainring either so not too concerned about the capacity
I've had one of those working great with a 9-39 cassette but that was on a 1x set up.
If it helps at all I did also have it working fine with an 11-36 cassette on a 2x set up, no problems with any shifting at all.

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Tifosiphil
Posts: 359
Joined: Wed Nov 14, 2018 11:09 pm

by Tifosiphil

CampagYOLO wrote:
Tue May 17, 2022 9:33 am
Tifosiphil wrote:
Tue May 17, 2022 9:22 am
Going to ask a slightly off topic question in here as we have a lot of knowledge.

Running current generation GRX 810 with 11-34 rear and 52/36 front at the moment but have an everesting coming up in July. Been running this combo find in training but want a couple of spare gears on the day. Can anyone seen any potential issues with me sticking an 11-40 cassette on the rear and staying to just the inner chainring. 6 more than Shimano recommends but I've heard a lot of reports of it working. I won't be in the big chainring either so not too concerned about the capacity
I've had one of those working great with a 9-39 cassette but that was on a 1x set up.
If it helps at all I did also have it working fine with an 11-36 cassette on a 2x set up, no problems with any shifting at all.
Perfect, thank you. Just looking at cheap options as it's only one day.

I'll look into an 11/36 and a 34t inner and then maybe a 11/40 cassette

CasualRider
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by CasualRider

Bumping up the thread. Anyone has experience with Ultegra on Gravel? I'm trying to understand why not. Currenly have sram 1x on gravel bike and not a fan. It's simply inferior to shimano in every way. I love DA on my road bike and thinking to put Ultegra on Gravel bike. I'm pretty high power to weight so 1-1 ratio is plenty for me even for steep stuff.

Thoughts?
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FIJIGabe
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by FIJIGabe

I think the problem you're going to run into with Ultegra 8100 on gravel is the gearing - it just isn't designed with gravel in mind. It appears Shimano has discontinued the previous generation 46T front ring, so the smallest you will find is a 50/34, which is a pretty big combo for most people. You might be able to make a "mullet" type build, with R8100 all around and a GRX crank, but I'm not sure if that will work.

Personally, I run GRX 1x on my gravel setup, and haven't had any issues, but it's up to everyone's personal preference, of course.

CasualRider
Posts: 118
Joined: Sat Sep 05, 2020 1:36 am

by CasualRider

FIJIGabe wrote:
Tue Apr 18, 2023 7:48 pm
I think the problem you're going to run into with Ultegra 8100 on gravel is the gearing - it just isn't designed with gravel in mind. It appears Shimano has discontinued the previous generation 46T front ring, so the smallest you will find is a 50/34, which is a pretty big combo for most people. You might be able to make a "mullet" type build, with R8100 all around and a GRX crank, but I'm not sure if that will work.

Personally, I run GRX 1x on my gravel setup, and haven't had any issues, but it's up to everyone's personal preference, of course.
Anything bad besides gearing? I'm fit enought to ride anything with 1-1 min gear. Currenly have 46T with 10-44 on my gravel and it's more than enough for me. For reference I'm just a touch under 4.8W per Kg. I was thinking 50/34 in the front and 11-34 in the back would make it a perfect setup.

I had 1x for about a year now and much prefer shimnano 2x.

m3bas
Posts: 94
Joined: Wed Dec 01, 2021 7:23 am

by m3bas

Seems like the pros all road DA 12 speed at the gravel worlds.
The guy who won our UCI qualifier event also ran DA 12, and that had some decently fast and technical descents. Clutch is probably better sometimes but seems like its not necessary.

CampagYOLO
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Joined: Thu May 06, 2021 3:58 pm

by CampagYOLO

With that kind of power output and also if the terrain isn't too steep in your area then that gearing seems fine to me.

Only issue is the lack of a clutch but plenty seem to ride without one on gravel without too many issues. Again it depends on the terrain you're riding on.

de lars cuevas
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Location: the Netherlands

by de lars cuevas

What's good for pro's ain't allways good for us mere mortals...

And... Since gravelbike frames are built for smaller chainrings and increasingly wider tyres, please do check if your frame of choice can even take a 50-34 Ultegra crank.

+1 on want for cluch and on smaller lowest gear!
Last edited by de lars cuevas on Wed Apr 19, 2023 8:16 pm, edited 1 time in total.

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