I know there are loads of threads on here but there are a few questions I can’t seem to find the answers to.

Extender cog for the rear … I’ve gone for a 32t oval front so would a 42t rear be a better match than a 40t if I’m past my best at climbing?

Also … Why can I not run a SLX 10 speed rear cassette with it … They usually say xt or xtr compatible … What’s different about the slx then?

Also … do I have to run a clutch rear mech … I have one … an SLX but would prefer to keep my xt if possible but it’s non-clutch?

It’s all very confusing!

42 will give a little more range so why not.

Slx is fine. The only issue is that they are riveted rather than bolted. You’ll need to cut the rivets or drill the the heads where as with an xt you just pop the screws out.

No need for a clutch. I have one but almost never use it.

First up don’t go 1×10 if you think you need easier gears for climbing.
Yes 42t expander gives you an easier gear, if you currently have a 40t run that and see.
The slx cassette first split like an xt/txt to remove your 17t sprocket for the expander to fit. You can split an slx but you need to knock out the pins holding it together.
You don’t have to have a clutch mech. Clutch will keep the chain tighter so less/no chance of it dropping and should be quieter. Again run the xt if you have it and see.
Hope that helps!

Oh gf has slx cassette and 40t expander. We just removed the 12t….and has been fine .
Whether that defeats the point of an expander is an argument for another thread……

40t vs 42t – yes, 42t would be better for climbing in a sense, but I’d argue it can be too much of a step up from 36->42t and that can be a bit jarring while riding so 40t can give you a better spread. It’s a personal choice at the end of the day.

SLX/XT cassette: I believe this is to do with the way the cassette breaks down. More specific info here: linky

Clutch: Yes, you can still use a non-clutched mech with an expander, there’s no problems there but as with any non-clutched 1x setup, it’ll generate more chain slap and have a higher risk of dropping a chain. The thick/thin ring up front will help reduce dropped chains though; really depends how hard (or daft) you ride.

I’ve just gone 1×10.
Running a 30T NW up front with a 11-36 Deore out back.
Not really tried in anger yet but a Lakes trip over NY will decide whether I need to go 11-40 in which case I’ll get a Sunrace 11-40 cassette. Running SLX clutch which keeps things nice and tight.

That’s good news, thanks …. which cog do you recommend I get rid of from the slx cassette?

Everywhere seems to say the 16 or 17 … Is there a definitive answer or just any.

My cassette is 11-36 …

gardron … That link is perfect …cheers

I’m hoping that it will be better for climbing than putting it in the granny when things get steep … I’m not really a spinner … never been too good at that but for the usual trail centre climbs like whites level or torch trail I seemed to be ok in the middle ring until recent years … But don’t like that pause when you have to stick it in the 22.

Plus I have this uncontrollable urge to try 1×10

Just go 1×11!!!

I removed both 16 and 17 and replaced with 15 cog. Smoother shift.

you mean 15 and 17 and replaced with a 16t…?

In my experience, NW rings make more of a difference regarding dropping chains than do clutch mechs. I’ve often got back off a ride to find that the clutch is in the “off” position but haven’t dropped the chain or noticed any more chain slap.

N.B. Any talk of gear ratios needs to also mention wheel size as that has an effect on what you run up front. I reckon 30T on a 29er, 32T on a 650b and 34T on a 26″ are about equal. Add two teeth to these sizes if you’ve got strong legs, maybe drop two teeth if you regularly ride in very hilly areas. I run a 32T on a 29er and haven’t yet needed the 40T on a trail centre climb.

sleigh62 – Member

That’s good news, thanks …. which cog do you recommend I get rid of from the slx cassette?

Everywhere seems to say the 16 or 17 … Is there a definitive answer or just any.

My cassette is 11-36 …

I’m running an SLX cassette on my 1×10 set up. When I fitted my 40t expander I removed the 11t (or 12t – can’t remember exactly). In any case, I didn’t split the cassette, just removed one of the loose smaller cogs. Works just fine. 🙂

I went 1×10 a few months ago , never been good on the climbs but I manage with a 40t expander no problem. I also use a non clutch xt rear mech from my previous 3×10 set up with a 32t superstar narrow wide chain ring. Always dropping the chain previously but since the swap it hasn’t happened once.