Beginner question- Do I need new cassette or a new chainset?
Discussion
My MTB has the SRAM NX system 1x11.
Chainring; 30T
Cassette: 11-42 (11,13,15,17,19,22,25,28,32,36,42)
A lot of the riding is with a child seat so a bit more weight and easy trails, but what I am finding is that the bike doesn't have so much resistance in the lowest gear when at speed on a flat/decline. And that is with a child and being a cautious rider so not going very fast at all.
And on steeper uphills, I could do with another higher gear, again carrying a bit of weight with the childseat won't help.
I can get:
Chainring options: change my 30 to any one of 32, 34, 36, 38
cassettes: change my 11-42 ((11,13,15,17,19,22,25,28,32,36,42)) with a 10-42 (10-12-14-16-18-21-24-28-32-36-42)
What do I need, new chainring or cassette, or both
Chainring; 30T
Cassette: 11-42 (11,13,15,17,19,22,25,28,32,36,42)
A lot of the riding is with a child seat so a bit more weight and easy trails, but what I am finding is that the bike doesn't have so much resistance in the lowest gear when at speed on a flat/decline. And that is with a child and being a cautious rider so not going very fast at all.
And on steeper uphills, I could do with another higher gear, again carrying a bit of weight with the childseat won't help.
I can get:
Chainring options: change my 30 to any one of 32, 34, 36, 38
cassettes: change my 11-42 ((11,13,15,17,19,22,25,28,32,36,42)) with a 10-42 (10-12-14-16-18-21-24-28-32-36-42)
What do I need, new chainring or cassette, or both

hyphen said:
My MTB has the SRAM NX system 1x11.
Chainring; 30T
Cassette: 11-42 (11,13,15,17,19,22,25,28,32,36,42)
A lot of the riding is with a child seat so a bit more weight and easy trails, but what I am finding is that the bike doesn't have so much resistance in the lowest gear when at speed on a flat/decline. And that is with a child and being a cautious rider so not going very fast at all.
And on steeper uphills, I could do with another higher gear, again carrying a bit of weight with the childseat won't help.
I can get:
Chainring options: change my 30 to any one of 32, 34, 36, 38
cassettes: change my 11-42 ((11,13,15,17,19,22,25,28,32,36,42)) with a 10-42 (10-12-14-16-18-21-24-28-32-36-42)
What do I need, new chainring or cassette, or both
It sounds like you're discovering the frustration of a 1x drivetrain!Chainring; 30T
Cassette: 11-42 (11,13,15,17,19,22,25,28,32,36,42)
A lot of the riding is with a child seat so a bit more weight and easy trails, but what I am finding is that the bike doesn't have so much resistance in the lowest gear when at speed on a flat/decline. And that is with a child and being a cautious rider so not going very fast at all.
And on steeper uphills, I could do with another higher gear, again carrying a bit of weight with the childseat won't help.
I can get:
Chainring options: change my 30 to any one of 32, 34, 36, 38
cassettes: change my 11-42 ((11,13,15,17,19,22,25,28,32,36,42)) with a 10-42 (10-12-14-16-18-21-24-28-32-36-42)
What do I need, new chainring or cassette, or both

Changing from the current 11-42 to 10-42 will give you slightly more on the flat/downhill without making the climbing harder.
Changing the chainring to any of the options listed would also give more on the flat/downhill, but would also make the climbing harder.
The only way you can make the climbing easier is to fit a cassette with something bigger than a 42.
Kermit power said:
It sounds like you're discovering the frustration of a 1x drivetrain!
...
The only way you can make the climbing easier is to fit a cassette with something bigger than a 42.
Surprised to hear, new to bikes and was aware that the NX is the entry level 1x so I kinda expected it was due to cheapness and could be fixed by upgrading up the range. ...
The only way you can make the climbing easier is to fit a cassette with something bigger than a 42.
Will get the cassette, and then wait for 1x12 to come down in price once 1x13 has come out! or wait a few years until we are on 1x18 or something.
Don't buy the 10-42 cassette!!!
I've just been having a bit more of a look at this groupset, and if I've understood it correctly, to change to the 10 tooth smallest cog, you'd also need to change your rear hub to a SRAM XD freewheel for it to fit, so probably not a cost-effective option.
The only change I can see that you could make it that I believe there's the option of a 28 tooth chainring for the NX groupset, which would make it easier up the steepest gradients, albeit exacerbate the problem of running out of gear when doing downhill.
Unfortunately, at the moment, I think you're stuck with that compromise, as you can't go beyond an 11-42 cassette.
I've just been having a bit more of a look at this groupset, and if I've understood it correctly, to change to the 10 tooth smallest cog, you'd also need to change your rear hub to a SRAM XD freewheel for it to fit, so probably not a cost-effective option.
The only change I can see that you could make it that I believe there's the option of a 28 tooth chainring for the NX groupset, which would make it easier up the steepest gradients, albeit exacerbate the problem of running out of gear when doing downhill.
Unfortunately, at the moment, I think you're stuck with that compromise, as you can't go beyond an 11-42 cassette.
30 42 is pretty up there with the easiest gears. My road bike is a triple with a granny gear and that is only 30 28.
You are going to struggle to get lower gears without a lot of expense or changing of parts. At the end of the day you are carrying a lot of extra weight on the back, it won't be easy if you go up steep slopes.
Have you thought about an electric bike? Sounds like it would be perfect for you.
You are going to struggle to get lower gears without a lot of expense or changing of parts. At the end of the day you are carrying a lot of extra weight on the back, it won't be easy if you go up steep slopes.
Have you thought about an electric bike? Sounds like it would be perfect for you.
Thanks all.
No, don't want an e-bike, I bought it to get fitter so would rather push up the hill until fit enough to ride up, will leave e-bikes till I get injured/very old.
Bike has aftermarket Fulcrum wheels already fitted so XD driver compatible, so will into cost of xd adapter and 10-42 cassette, or wait for the X01 eagle to get more mainstream. As otherwise the groupset will be worth more than the bike. The NX system otherwise is lovely and will live with it in the meantime as don't want to go 2x and make maintenance a bit more complicated/time consuming.
Or maybe the right answer is to get a new bike with a 14 speed Rohloff
No, don't want an e-bike, I bought it to get fitter so would rather push up the hill until fit enough to ride up, will leave e-bikes till I get injured/very old.
Bike has aftermarket Fulcrum wheels already fitted so XD driver compatible, so will into cost of xd adapter and 10-42 cassette, or wait for the X01 eagle to get more mainstream. As otherwise the groupset will be worth more than the bike. The NX system otherwise is lovely and will live with it in the meantime as don't want to go 2x and make maintenance a bit more complicated/time consuming.
Or maybe the right answer is to get a new bike with a 14 speed Rohloff

Edited by hyphen on Tuesday 29th August 12:26
I run 30T - 11-42T on my main bike, and don't have any problems with it, I accept that the ease of climbing is the tradeoff to lack of speed on downhill/tarmac.
On my other bike, which has the child seat mounted, I have 10sp 32T - 11-36T and find that fine for all but the steepest of climbs, however I tend to avoid those when I've got my son on the back.
On my other bike, which has the child seat mounted, I have 10sp 32T - 11-36T and find that fine for all but the steepest of climbs, however I tend to avoid those when I've got my son on the back.
Very unlikely, I'm still learning so never go too fast, even when on my own! Bike was previously owned by a more experienced rider who upgraded most things apart from forks and gearset, so seat, seat post, brakes, wheels, grips, stem, handlebar clamp, handlebar and he did specifically say to me it was a fast bike.
As per my original post, it isn't freewheeling though, just not a lot of resistance which feels strange, pedalling still makes it go faster. Might just be me thinking this is wrong though as I don't have anything to compare to.
Also chain I'm using is a XX1 which is the top of the 1x range and designed for the other XX1 items rather than the low end NX I have, maybe that has an effect, or because it is brand new chain with factory lubricant. Dunno.
But anyway, will live with it for now and get used to it. Otherwise having lots of fun
As per my original post, it isn't freewheeling though, just not a lot of resistance which feels strange, pedalling still makes it go faster. Might just be me thinking this is wrong though as I don't have anything to compare to.
Also chain I'm using is a XX1 which is the top of the 1x range and designed for the other XX1 items rather than the low end NX I have, maybe that has an effect, or because it is brand new chain with factory lubricant. Dunno.
But anyway, will live with it for now and get used to it. Otherwise having lots of fun

Edited by hyphen on Tuesday 29th August 14:16
I'm not going to imply that you're doing anything wrong or that this necessarily applies to you, but most novice cyclists' pedalling cadence is way too low, and they think that there should always be a lot of resistance when they pedal - when in fact upping your cadence and learning to spin will be one of the best things you can do. As I said, a decent rpm for pedalling on smooth(ish) surfaces is 90rpm, which for a 650b bike and 30/11 gearing gives just over 20mph. It will feel strange if you're not used to it though, but it'll teach you to pedal much more efficiently if you gear down and spin rather than pushing hard against too high a gear. Enjoy!
Kermit power said:
gp1699 said:
I would go for a bigger chain ring, I run Sram 1x11 xo1 with a 34.
It gets me up just about anything and I run out of gears at around 57kmh according to strava ...
That's sure to answer the OP's desire to get up hills more easily! It gets me up just about anything and I run out of gears at around 57kmh according to strava ...


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