I am very tempted by a SRAM X01 AXS upgrade kit for my Nukeproof Mega.

Currently have a 30t chainring and an 11-42t cassette and I’m quite happe with that range. All the 12s cassettes I’ve found have 50t as the largest sprocket which I don’t really want.
Are there any 12s cassettes with 42t as the largest sprocket?

Thanks

XT and XTR available in 10-45T version. That’s the smallest 12 speed I know of (other than Sram AXS/Campag road units) You’d have to change freehub though.

Get a bigger chainring?

Thanks,
I could get a bigger chainring. But I rarely use the smallest 11t sprocket with a 30t as it is. So having a 34t chainring with a 9t or 10t cog and I’m going to use it even less.

Will shimano cassettes work with sram 12s groupset… Sorry if its a daft question.
Realistically I don’t need 12s…. I was quite happy with 10s to be honest, but I am keen on the AXS aspect.

Hot Hope Pro 4, so I can swap freehub to either XD or microspline

Will shimano cassettes work with sram 12s groupset…

A few people seem to have got Sram cassettes working with Shimano mechs and shifters, which would imply it works the other way round, but my experience of a Sram 12s cassette with Shimano bits is that it doesn’t work and it’s best to commit to full Shimano. The XT mech and shifter are £100 together from CRC at the moment and I’d say it’s worth it for a set up that works properly.

E13 do one that’s a fair whack of money but 9-46.

https://www.bike24.com/p2309432.html

ZTTO also do a 9-46 for XD drivers that’s much cheaper.

https://www.aliexpress.com/item/4000516596770.html?spm=a2g0o.productlist.0.0.3f123c14z5qGk7&algo_pvid=2c74cacc-9612-4e5f-9ee6-170866cfd104&algo_expid=2c74cacc-9612-4e5f-9ee6-170866cfd104-8&btsid=da5de3e6-f665-4063-bf66-ca12a82c7c2b&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_53

If you are happy with 42t being the biggest cog then do you really need 12 speed?

but my experience of a Sram 12s cassette with Shimano bits is that it doesn’t work

What happened? It’s the first time I hear of such incompatibility?

Could you run the sram AXS shifter / mech but with shimano cassette / chain / cranks? That way all the gears and chain work well together and you get the whizzy shifting with the smaller cassette?

Although 45t isn’t much smaller than 50 / I don’t know if it massively closes any gaps between ratios? In which case you may as well run sram

What happened? It’s the first time I hear of such incompatibility?

I’m not the only one that’s noticed this – the spacing is different by a few fractions of a millimetre so if you set it up in the middle of the block the shifting goes slightly awry at the extremes of the cassette. Some people it seems to work OK for, for me it results in finnicky, inconsistent shifts. I occassionally have to double shift at the top and bottom of the cassette. If you’re happy with Tourney level shifting then it’s fine but if you’re used to Sram AXS you probably won’t be.

Sram 12spd cassette, XTR M9100 mech and an X01 eagle shifter. No issues with shifting in any gears. Been running since the start of December with a dozen or so rides.

https://www.instagram.com/p/B6Bh_fFHRN-/

If you are happy with 42t being the biggest cog then do you really need 12 speed?

^^^ this

Although you don’t say if you are running 10 or 11 speed currently.

Know a few folk who run AXS with XTR chain and cassette. No issues.

To be honest, it sounds like the best of both worlds, Shimano shifting under power, shifted by an AXS mech.

Garbaruk do a 10-48 XD cassette, not much smaller though, TBH, but keeps your freehub

https://r2-bike.com/GARBARUK-Cassette-12-speed-10-50-Teeth-for-SRAM-XD

Meanwhile – KCNC do a 9-52, because more.

https://r2-bike.com/KCNC-Cassette-12-fach-MTB-9-52-Teeth

Thanks for the replies.
I don’t NEED 12s at all, currently have 11s and happy with that and was happy with 10s on previous bikes.

However it’s the AXS wireless setup that I’m tempted by… And if a 200mm reverb AXS is released even better.

I’m not the only one that’s noticed this – the spacing is different by a few fractions of a millimetre so if you set it up in the middle of the block the shifting goes slightly awry at the extremes of the cassette. Some people it seems to work OK for, for me it results in finnicky, inconsistent shifts. I occassionally have to double shift at the top and bottom of the cassette. If you’re happy with Tourney level shifting then it’s fine but if you’re used to Sram AXS you probably won’t be.

Sounds like a set up problem rather than i compatibility as plenty get perfect shifting it would seem.

Sounds like a set up problem rather than i compatibility as plenty get perfect shifting it would seem.

It’s not a setup issue. I can set up gears, I even used to do it for a living.

Here’s a quote from another thread on STW on it-

I believe there is a tiny difference the the spacing of the sprockets, something like 0.1mm, between Shimano 12sp and SRAM Eagle. That would equate to 1.2mm across the whole cassette.

To miniimize the amount of drift as you go through the gears, I would suggest setting it up and tuning in gears 6&7.

1.2mm over the width of a cassette where the spacing between cogs is so close adds up and means it doesn’t work as well as it should.

Here’s a table from Weightweenies showing the difference over the whole of the cassette depending on where you set the gears between Sram and Shimano cassettes-

Some people may find it works acceptably, but it doesn’t work properly.

@munrobiker. Thanks for that, appreciated. Clearly not entirely compatible.

Does using XT shifter and mech on an Eagle cassette resolve it?

Exactly the same thoughts here. Don’t need 12 speed, entirely happy with 10-42 range, would like AXS.

I’m interested in your friends set up @tomhoward.

Everything I’ve read points towards something that chimes with that weightweenies table where the best you can do is get the middle right and the ends ‘good enough’. But no one can ever explain what the real life experience is. That it works in a stand or at spinning effort isn’t enough to convince me.

I’ve asked Rotor which spacing (Sram or Shimano) their 12 speed cassette uses (11-39 and 11-46, fits on Shimano HG freehub) and they say ‘both’! Which either means they don’t know or that the difference is so small that no one needs to care about those fractions of a millimetre!

OP, check out Rotor. And watch out for chainring compatibility if you go the 10-45 Shimano cassette and chain – another chance at incompatibility!!

You can mix and match AXS stuff, so you could run a force/red AXS rear mech with the eagle AXS controller, and a 10-33t cassette, but I think you’d need an XDR driver, as they’re not compatiable that way around (they are the other, XD cassette on a n XDR driver, needs a thin spacer).

Everything I’ve read points towards something that chimes with that weightweenies table where the best you can do is get the middle right and the ends ‘good enough’. But no one can ever explain what the real life experience is. That it works in a stand or at spinning effort isn’t enough to convince me.

Not in my world. Shifts as well as my old 11spd XX1 setup, also shifts as well as my old XX1 Eagle setup.

Using an XX1 cassette on one wheelset, and an X01 on another, XTR shifter and mech. Shifts perfectly in every gear.

I’m not known for my super maintenance skills, so if I can manage to get it right, I’m sure others can (and a lot more people seem to be able to get it right, than wrong).

If it shifts as well as your old setup doesn’t that mean it shifts worse than it should, considering the performance of Shimano 1×12 is supposed to be a significant step up especially shifting under load?
Can’t say from experience yet but just about to change to XT 1×12 and I’m expecting improved shifting from what I have read.

Putting it simply, I press the lever it goes up, I press the lever it goes down.

Maybe if I was in a lab and test conditions it would shift better, but my bike is invariably covered in mud or dust, or something to hamper performance.

The last thing I think about is how smooth a shift is when I’m pushing on, or racing. All I want is to press a lever and for it to work, which it does. Can’t really ask for much more.

Fair enough. I have a slightly different compatibility issue which is that I can’t leave my XX1 chainset on if I want to change to 1X12 (so I’m told anyway) so I’m going to change the whole drivetrain, but the new XT 1X12 is such good value it’s not really a problem. AXS…..not so much on the value for money….!

Does using XT shifter and mech on an Eagle cassette resolve it?

My set up is XTR with an Eagle cassette and it doesn’t work properly.

Everything I’ve read points towards something that chimes with that weightweenies table where the best you can do is get the middle right and the ends ‘good enough’. But no one can ever explain what the real life experience is. That it works in a stand or at spinning effort isn’t enough to convince me.

Mine shifts absolutely fine in all gears. I’d even say better than when it had an eagle mech, biggest difference is the clutch actually works and my bike is back to being silent.

I set the end stops and then set the derailleur up on the middle gear, then tweaked it as I would for sram to get it shifting as it should.

Imagine how gutted you’d feel if you bought AXS then smashed the longer rear mech that you didn’t really need and which costs £800 or whatever on a rock?

Forget about it and have a nice holiday instead?

Imagine if you’d bought AXS, got to where you were riding and it was flat.

Oh I know it’s an irrational want and I can spend the money on other things/holidays etc… But when does rationale and logic come in to bike part purchases.

Thanks for all the replies

The SRAM XG-1270 Force cassette is available in 11-33 and fits the XD driver.