Will GRX handle a 11-46 cassette?
#1
Senior Member
Thread Starter
Will GRX handle a 11-46 cassette?
Getting GRX for my gravel build and want to put an 11-46 cassette on it. Thinking that an adjustment of the B screw would allow it.
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
Thanks in advance.
Brandon
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
Thanks in advance.
Brandon
#3
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Getting GRX for my gravel build and want to put an 11-46 cassette on it. Thinking that an adjustment of the B screw would allow it.
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
Thanks in advance.
Brandon
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
Thanks in advance.
Brandon
https://www.coloradocyclist.com/shim...ear-derailleur
Features
- For use with single ring crankset, 11-speed
- Weight: 264 grams
- Adjustable chain stabilizer prevents chain slapping and drops
- Toggle clutch ON/OFF to match the terrain
- Switch stabilizer ON/OFF to match the terrain
- Gravel-tuned clutch tension
- Total capacity: 31T
- Low sprocket: Maximum 42T/Minimum 40T
- Top sprocket: Maximum 11T/Minimum 11T
- Cassette Size: 11-40t to 11-42t
#4
nothing to see here
Getting GRX for my gravel build and want to put an 11-46 cassette on it. Thinking that an adjustment of the B screw would allow it.
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
Thanks in advance.
Brandon
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
Thanks in advance.
Brandon
Nope, per official numbers The 1X11 GRX RDs top at at 11-42, officially. The 2x11 top out at 11-34.
https://www.coloradocyclist.com/shim...ear-derailleur
Features
https://www.coloradocyclist.com/shim...ear-derailleur
Features
- For use with single ring crankset, 11-speed
- Weight: 264 grams
- Adjustable chain stabilizer prevents chain slapping and drops
- Toggle clutch ON/OFF to match the terrain
- Switch stabilizer ON/OFF to match the terrain
- Gravel-tuned clutch tension
- Total capacity: 31T
- Low sprocket: Maximum 42T/Minimum 40T
- Top sprocket: Maximum 11T/Minimum 11T
- Cassette Size: 11-40t to 11-42t
But, it's well known that Shimano is conservative with its max cog capacity of their rear derailleurs. Most likely it will work fine with some b-screw adjustment.
I'm contemplating a similar set up for my gravel bike. Please report back with how it works out for you.
#5
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Getting GRX for my gravel build and want to put an 11-46 cassette on it. Thinking that an adjustment of the B screw would allow it.
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
I can't find anything that shows if it's possible.
Anyone know first hand if it will work? My other option would be to use an XT rear mech.
For what its worth, a 30/34 bailout is the same as a 40/46 bailout in terms of gear inches. So a simple 46/30 crank mated to an 11-34 cassette will give you the same bailout gearing as a 40/46 while also giving tighter shift jumps and more overall gear range.
But hey, you do save a whopping 50g by going 1x, so if that is the driving motivation, it makes sense(2068g vs 2108g).
#6
Senior Member
Thread Starter
Thanks all. I'm going Di2 and 1x. Mtn Di2 rear derailleurs will most certainly work with road Di2 shifters. Common actually.
I ended up finding a 38t chainring from Wolftooth so I'll go that route with a 11-42 in the back. Should be good enough for just about everything out there.
I ended up finding a 38t chainring from Wolftooth so I'll go that route with a 11-42 in the back. Should be good enough for just about everything out there.
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#7
Senior Member
Unfortunately, Shimano killed Di2 for 12-speed MTB. Otherwise, that new 10-45 MTB cassette plus a 12-speed Di2 RD and the new GRX Di2 brifters would’ve been perfect for 1x gravel.
Honestly, for all the fuss Shimano made this past spring about their big “gravel listening tour”, I still don’t think they get it.
Honestly, for all the fuss Shimano made this past spring about their big “gravel listening tour”, I still don’t think they get it.
Last edited by john.b; 10-09-19 at 05:37 PM.
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#8
Senior Member
Unfortunately, Shimano killed Di2 for 12-speed MTB. Otherwise, that new 10-45 MTB cassette plus a 12-speed Di2 RD and the new GRX Di2 brifters would’ve been perfect for 1x gravel.
Honestly, for all the fuss Shimano made this past spring about their big “gravel listening tour”, I still don’t think they get it.
Honestly, for all the fuss Shimano made this past spring about their big “gravel listening tour”, I still don’t think they get it.
#9
Senior Member
Probably a large majority of people who ride any kind of mountainous stuff. In my area, we've got plenty of gravel climbs that average 12% or more over a mile at a time. And check out this gorgeous road that one of my friends recently found:
I suppose "need" is a strong word, but if it's a question of what's optimal, I actually think that most road bikes in hilly areas should come with ratios of 1:1 or lower, whether intended for gravel or otherwise. Even in the paved lowlands around here, I see tons of people badly bottomed out on their gearing during climbs, and people avoiding very fun roads simply because the gradients get steep. That's awful.
Ideally, common chainring combinations would span a much wider range than they currently do. From what I can tell, a majority of people on road bikes have very little use for the top-end on modern road bikes. For the weaker riders, a 42-26 or even 40-24 would offer adequate top-end in a 1x-plus-granny scheme, while permitting a comfortably tight-spaced cassette.
I suppose "need" is a strong word, but if it's a question of what's optimal, I actually think that most road bikes in hilly areas should come with ratios of 1:1 or lower, whether intended for gravel or otherwise. Even in the paved lowlands around here, I see tons of people badly bottomed out on their gearing during climbs, and people avoiding very fun roads simply because the gradients get steep. That's awful.
Ideally, common chainring combinations would span a much wider range than they currently do. From what I can tell, a majority of people on road bikes have very little use for the top-end on modern road bikes. For the weaker riders, a 42-26 or even 40-24 would offer adequate top-end in a 1x-plus-granny scheme, while permitting a comfortably tight-spaced cassette.
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#10
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Depends on the surface, and how big your tires are.
I have a 30/32 bailout and with 700Cx42mm tires I've needed it if not a bit lower. Could not stand for more power without just spinning the wheel. 15% farm MMR with pea gravel are mean.
I have a 30/32 bailout and with 700Cx42mm tires I've needed it if not a bit lower. Could not stand for more power without just spinning the wheel. 15% farm MMR with pea gravel are mean.
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#11
nothing to see here
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#12
Senior Member
Probably a large majority of people who ride any kind of mountainous stuff. In my area, we've got plenty of gravel climbs that average 12% or more over a mile at a time. And check out this gorgeous road that one of my friends recently found:
I suppose "need" is a strong word, but if it's a question of what's optimal, I actually think that most road bikes in hilly areas should come with ratios of 1:1 or lower, whether intended for gravel or otherwise. Even in the paved lowlands around here, I see tons of people badly bottomed out on their gearing during climbs, and people avoiding very fun roads simply because the gradients get steep. That's awful.
Ideally, common chainring combinations would span a much wider range than they currently do. From what I can tell, a majority of people on road bikes have very little use for the top-end on modern road bikes. For the weaker riders, a 42-26 or even 40-24 would offer adequate top-end in a 1x-plus-granny scheme, while permitting a comfortably tight-spaced cassette.
I suppose "need" is a strong word, but if it's a question of what's optimal, I actually think that most road bikes in hilly areas should come with ratios of 1:1 or lower, whether intended for gravel or otherwise. Even in the paved lowlands around here, I see tons of people badly bottomed out on their gearing during climbs, and people avoiding very fun roads simply because the gradients get steep. That's awful.
Ideally, common chainring combinations would span a much wider range than they currently do. From what I can tell, a majority of people on road bikes have very little use for the top-end on modern road bikes. For the weaker riders, a 42-26 or even 40-24 would offer adequate top-end in a 1x-plus-granny scheme, while permitting a comfortably tight-spaced cassette.
#13
Senior Member
All the hard gravel rides have like 5-10% of the participation numbers compared to the easier less hilly rides, and we have lots of mounatains here in the PNW.
This is partly a chicken-and-egg issue. By and large, you don't need to be able to put out a lot of power to get up steep hills, if you've got appropriate gearing. I've seen very few people fail to have a blast on foothills gravel rides out here, but it's hard to get people to do it if their bike isn't suitable for the job.
This is true even for the lower paved hills in the populated areas. There's zero technicality to paved climbing; if someone says that a paved hill is "hard to get up", that's a problem with their bike.
Last edited by HTupolev; 10-10-19 at 11:57 AM.
#14
Senior Member
That particular hill is an extreme case, but...
This is partly a chicken-and-egg issue. By and large, you don't need to be able to put out a lot of power to get up steep hills, if you've got appropriate gearing. I've seen very few people fail to have a blast on foothills gravel rides out here, but it's hard to get people to do it if their bike isn't suitable for the job.
This is true even for the lower paved hills in the populated areas. There's zero technicality to paved climbing; if someone says that a paved hill is "hard to get up", that's a problem with their bike.
This is partly a chicken-and-egg issue. By and large, you don't need to be able to put out a lot of power to get up steep hills, if you've got appropriate gearing. I've seen very few people fail to have a blast on foothills gravel rides out here, but it's hard to get people to do it if their bike isn't suitable for the job.
This is true even for the lower paved hills in the populated areas. There's zero technicality to paved climbing; if someone says that a paved hill is "hard to get up", that's a problem with their bike.
#15
Senior Member
I don't know what the solution is, but I don't find the lack of standard options for smaller rings to be good evidence that gearing isn't a significant hindrance here.
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#16
Senior Member
This issue doesn't have anything specifically to do with gravel, gravel just puts a bit of additional pressure on it. Insufficient low gearing has been a blind spot in road cycling fashion since the dawn of time. Rivendell Reader 34 is fourteen years old but still very interesting, look at page 26 here: Kozo Shimano admits that 53-39 was standard on recreational bikes mostly because the perception from the company leaders was that cyclists would want cranks that didn't look like Lance's cranks, and also admits that he had a better experience on smaller rings. In other words, he knew that gearing was a problem, but assumed that fixing the problem could be a marketability issue.
I don't know what the solution is, but I don't find the lack of standard options for smaller rings to be good evidence that gearing isn't a significant hindrance here.
I don't know what the solution is, but I don't find the lack of standard options for smaller rings to be good evidence that gearing isn't a significant hindrance here.
#17
Senior Member
They have the cassettes already, if they thought there was a huge market and people would be happier with 46-30 11-42 they could have put that out instead
I'm not saying that there is a market. I'm saying that there probably should be, and that it's frustrating that the big brands have been so hesitant to even test the waters. Pretty much every mainstream attempt to reduce standard chainring road chainring sizes over the last half-century has succeeded, but it's been baby steps the whole way. That's silly, like watching a programmer script a linear search when a binary search would be far more appropriate.
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#18
Senior Member
Been thinking about a RX800 GS or M8000 with a tanpan.
#19
Senior Member
Probably with a 46/30 or a 48/31. 50/34 11-40 required a full length uncut chain and the b-screw maxed out on my CAADX. You could flip the b-screw or use a road link easily
#20
Senior Member
Chain rings are 48/36 currently so I should be OK there, was just curious if the rx800 cage can clear a 42T with the b-screw alone. I guess one way to know for sure is try it, then buy a roadlink if it fails.
#21
Senior Member
Would probably work by why not throw a 34t on there and use the closer spaced 11-40 cassette?
#22
Senior Member
#23
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#24
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#25
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Do I misunderstand what power means? Isn't it true that for a given hill, you need the same amount of power to get up that hill, regardless of what gearing you have? I suppose the limiting factor is speed you're going and if you can keep the bike upright at eg. sub 3mph speeds or whatnot.