I've not paid much attention to this over the years as since 1x11 appeared I've only ever worked with complete sets of parts. Now looking at fixing up and old bike using parts bin stuff.
I'm assuming I need a new chainring (for a 11speed chain). Where does the chainring need to sit on a triple to get the right chainline?
Have there been any different freehub standards on MTBs or will a 10+ year old wheel take a Shimano 11 spd cassette?
Yes to the latter question.
With 11 speed you will need to put it where the middle ring went and maybe add some spacers as the cassette is wider. Try it and see, often if it's not quite right it'll change down from he biggest to 2nd biggest cog when back pedalling.
If you've already got a 1x10/1x9 chainring, no need for a new chainring (if you've got 2 or 3x, then you will. Make sure it's a narrow-wide chainring). You'll also need new mech and shifter.
11 speed now has two standards, regular Shimano freehub and SRAM's XD freehub.
If you get a SRAM 11 speed cassette you'll need a SRAM XD* freehub, whereas Shimano have retained existing freehub and in most(?) cases an existing 9/10 speed freehub I believe will take an 11 speed Shimano cassette (possibly may have to mess with spacers or not).
* - with an exception that SRAM's low end cheap and heavy NX cassette is Shimano freehub.
Not sure with 1x11 but I had a 1x10 set up briefly with a triple and the chainring goes in the middle and I recall was a faff as the tabs needed filling down to fit as they're designed for 1x spiders.
If your crank is a SRAM GXP you might be able to swap the spider for a single, or you can just buy a spiderless chainring.
p.s. you've also got the choice of round chainring or oval 😉
Try it and see, often if it's not quite right it'll change down from he biggest to 2nd biggest cog when back pedalling.
My all new XT M8000 does this anyway...
Sounds like you need Xtr..... 😉
GX 11 speed rear mechs on both MTB's, XT cassette on one, GX on t'other, none of them drop down when back pedalling, though I only know this by trying it after reading folks moans on here about it, why you'd do it on the trail I haven't a clue.
A half/quarter rotation on a techy climb is about all I can imagine you'd do?.
Chainrings are compatible. Marketing suggests the 11 speed rings might be better but tbh the 10 speed rings work so well it's not worth worrying about.
Chainline- this might anger the chain gods but it's not that important. Single ring in the wrong place just gives you pretty similar chainline to what we've always had with multi ring setups and we never really stressed about doubles, or using the outer gears in the middle ring. Also, in practice I probably spend more time in the bottom half of the block so is perfect middle chainline even the most appropriate? I don't know, but mostly I just don't stress, I have wee variations in chainline in all my bikes and they all work grand.
Last thing is, Shimano 1x11 has very little advantage over 1x10. SRAM gets you the wider range cassettes, Shimano do have an 11-46 now but that's not much wider than the common 11-42 for 10 speed. Obviously if you're starting from scratch it makes more sense to go 11 but if you already have 10 it's a marginal gain to go to Shimano. And not even that massive a gain going to SRAM tbh.
1 x 11 conversion - what's different?
In my experience so far it costs twice as much as 9 or 10 speed parts and lasts half as long 😆
You'll need:
A "narrow wide" chainring in the middle ring position on a triple crank, or outer with spacer on a double
11 speed cassette Sunrace are cheaper than XT and some say better
11 speed mtb shifter
11 speed mtb clutch rear mech
11 speed chain
I run 11-46 with a 32 upfront so I still have a granny gear.
If you are getting a new hub, then maybe best to run Sram XD 10-42 cassette, these need different free hub - some hubs have these available.
none of them drop down when back pedalling, though I only know this by trying it after reading folks moans on here about it, why you'd do it on the trail I haven't a clue.A half/quarter rotation on a techy climb is about all I can imagine you'd do?.
My SRAM 1x11 is fine. The Shimano isn't.
Use? half back pedal do level off when going over rocks/logs, between tree stumps it doesn't really matter much. Setting up pedals to restart on a steep slope was the main issue.