Thinking of 32t chainring with 11-34 cassette.

Is some sort of chain guide always necessary, or just if using a ramped chainring?

some people get away with it but most dont. you can just use your front mech with the limit screws set to guide the chain on the right line, or one of those mrp/e13 guides, the ones with the bottom rollers as well are for more lairy riding.

Yes you will need a guide of some sort, and potentially a bottom roller too (some setups get away with it, some done)

Could also consider using a bashring and an n-gear jump stop

Ok, so looks like I'm going to need something.

Nuke – your getting technical now!! 😳

I used an E13 guide ring (unramped chainring) and had the chain as short as possible and didn't need any guides.

Rotor chainring now needs a guide though

Not trying to flame or anything but if you're going to fit a guide and bottom roller, what's the point in going 1×9? The weight of 1 ring and 1 shifter? The extra 1" ground clearance at the BB? I can see the point of SS, and I can see the point of 24 speed, but not somewhere in between.

I also don't follow the need for a bottom roller, you can have a shorter chain than with a 3×9 and the bottom section sees no different circumstances than a 3×9, and they don't fall off the rings all the time?

Coffeeking. I went from 2×9 to 1×9 and my whole guide and roller setup weighs less than my front mech did. So I save the excess there plus my granny plus a big plastic bash plus the shifter and for what its worth some jagwire inner and outer. So probably about 3-400g so not far off 1lb!

what i_ache said, you save 300-500g depending on which guide you use.

the bottom roller definitely makes a difference in the rough stuff. if you think how much your chain bounces around even when its run tight, which if you are going downhill it probably isnt that tight because you would be lower down the cassette, its easy to see how your chain can get dropped. a bottom roller means that all that bouncing around doesnt affect the chains line as it leaves the chainring.

for me the whole point of going 1×9 was to keep the chain on, even run short and tight id still drop it in the rocky stuff all the time. good for fitness too, though thats more of a byproduct than a reason.

if you arent dropping your chain all the time then just dont bother.

OK so there's a reasonable weight saving, and if you never use the other rings then sure, that makes sense. I'm still not sure why you need a bottom roller any more than you do with a normal gear setup. It's no different to using 34/12 on a 3×9 setup (which I do fairly regularly with no bottom guide?). I'm guessing I'm missing something, but it does seem like a solution to fix a non-problem, unless you back-pedal a lot while descending.

Apart from the chain potentially falling off without a chain guide I prefer the nice quiet ride a chain guide gives. Can't stand the rattle and crash of standard systems on rough ground. Hence my lg1 guide with little bits of velcro here and there to keep it as silent as possible.

I've gone to 1×9 and use an MRP 1x guide, it's for my 456 so just general riding around. It does me for most riding and simplifies things too. Although setting the guide up was more hassle than I expected with effing around with the chain line.

I didn't do it for weight saving and struggle to understand the rationale behind factoring the weight of a bashring into the whole weight saving equation of going 1×9. Surely if you're that bothered about weight saving you could just leave the bashring off on a 2 ring set up and save weight in that configuration.

I think you do need a guide of some sort with 1×9 I tried it without and lost the chain a lot.

Yup as st says, I also tried running 1×9 without a guide – short chain, short cage mech, etc. – but still occasionally lost the chain on bumpy sections. So a guide is defo needed. The Pauls Chain Keeper is the most elegant solution I've found. Here's my setup:

It certainly isn't a weight saving plan, it's SS at the moment!!

Once the mud subsides a bit, thought I'd look at getting the bits together now.

I'm thinking of using it for Mayhem and the Bonty and don't fancy doing them SS. I think 1×9 on my 29er would be perfect.

The Paul's chain keeper looks simplicity itself, but I prefer the looks of the MRP 1.x and vanity will win every time 😆

coffeeking, you dont need to backpedal for the chain to come off without a bottom roller, you just have to pin it(TM) 8)

ive found it much more of an issue with full sussers not having a bottom roller than hardtails, probably due to the greater change in chain tension. or something…