1x versus 2x for old 26" MTB build
 

I'm getting ready to assemble another MTB and thinking about trying something different this time. My other MTB (which might get drop bars...) is pretty traditional with Shimano trigger shifters, 8-speed 11-34 cassette, and an XT square taper crank setup with 26/36 (Biopace!) chainrings.

My new frame is also 26", hardtail, rim brake. I don't have all the components I need so it's a bit open ended. I like my current setup a lot but wondering if 1x might be a better way to go. The cassette is obviously heavier but it eliminates a chainring, front derailer, front shifter, etc. I'm confident I can get a gear range I'm happy with (or I won't do it...) Has anyone done the math on this regarding weight? Is 1x actually lighter or is it just a way for OEMs to save money? If I go 1x, any crank recommendations? I have to imagine there's something out there that's lighter than the old square taper cranks I run on everything. Just keep in mind it needs appropriate chainline for a 135mm rear end.

The real reason to do 1x11 or 12, the reason it so quickly gained popularity and SRAM beat out Shimano for a few years, is that front shifting sucks. There are other reasons too that have to do with rear suspension but that's not relevant to conversions. The premium 1x systems are lighter but they depend on very clever and expensive cassettes to get there, and you need a different rear hub. In the "refurbishing old MTB" price range, the cassettes weigh well north of a pound, pretty much eating any weight savings, and you need the right chain ring too so you are looking at approaching $200 range to convert if you buy all new parts. I'm not saying no! I put 1x on my old tandem and it makes me very happy. But not for weight.

If you really want weight savings from the drivetrain, 1x1. If you can tolerate a pretty short gear range for your 1x, I think you can still get XT 10 speed 11-36 cassettes and Zee shifty bits, but I think the lightweight 9 speed cassettes are gone

Sunrace has some 9speed 11-50 cassettes among other things. I run an 8 speed 11-42 on my 26r with a triple up front.

I'm not opposed to spending some money. Let's say new Deore or used XT as a price point. I was thinking 1x10 but an 11 speed Shimano MTB cassette will also fit on a traditional 8/9/10 speed Shimano freehub, so that's an option.

Another concern is future parts availability. I'd rather not setup something with parts that are barely find-able now, only to completely vanish in a year when 13 or 14 or 15 or whatever speed comes out. Things are being made "obsolete" at a rapid pace today, especially in the MTB world. I don't want to capture a moment in time that vanishes and then the entire drivetrain is worthless if one part goes.

What rear derailer are you using? I'm not aware of any 8/9 speed rears that will shift a 42T without the use of a Wolf Tooth RoadLink (which I would be willing to use.) Also, that is a lot of gear!

You might want to look into Microshift’s AdventX 1x drivetrain. For 10 speeds, it offers a very wide and smart range: 11-48t. You can use a normal HG hub, regular 10-speed chains. Lots of 1X cranksets (from other brands) to choose from. It’s gotten great reviews.

https://m.pinkbike.com/news/first-lo...aver-2020.html

I've avoided Microshift as it always seemed like cheap knockoff stuff, but it's been years since I've built up a MTB. Sounds like this is worth considering. It certainly checks all the boxes.

I know what you mean about Microshift as I felt the same way, but they definitely seem to be creating a new image. I recently read a comment from Steve at YouTube’s Hardtail Party channel indicating that he has switched all of his older MTB’s to this new drivetrain. That is very encouraging and, actually, a big seal of approval. That guy tests a lot of components on a weekly basis.

A lot of people have that feeling on Microshift. I wanted to hate on them for years but honestly I keep seeing the stuff they do and am impressed. They make thumb shifters and bar end shifters for just about everything including modern stuff they have a decently thoughtout drivetrain for MTB and gravel that isn't out of the park expensive and even their mid tier shifters aren't too bad. I have a friend and co-worker/mechanic and she has the high end microshift carbon groupset from a few years ago and she is quite happy with it and honestly it is a good look.

I think a lot of people rip on them because they do see the bad stuff and see it a lot of cheaper bikes and don't really understand the full scope of what they have or just know XT and XTR good SRAM XXXXX10101010 is good but I think the tide is starting to change a little.

If I were doing 1x MTB 10 speed and up would probably be the lower limit, If I was doing 9 speed or below 2x or 3x would be what I go with personally. However it depends on your shifting as with Advent you can do a wide range 1x9 and if you aren't someone who will miss the cassette cogs that aren't there go for it.

I went 1x9 with one of my mtb's and definitely do not miss shifting up front. Now all my left hand has is my dropper post lever! As for gearing, I didn't really think about it and just slapped on whatever I thought was good enough and it is save for any really high-speed runs where I run out of gears. lol

Just remembered - on my current flat bar conversion I'm thinking of a Zee RD with 11 speed shifter and roadie cassette. The CS-HG700 and 800 11-34 cassettes will go on a MTB freehub. That gives tighter shifts than a 10 speed 11-36 but does not even tickle the gear range of the bigger cassettes, I thought it might be appropriate for my gravelybike. They follow the customary 105 / Ultegra formula where the 700 has one aluminum spider and the Ultegra has two. Combining that with the Zee RD is a pretty good deal for weight because it's just smaller than the later RD's

I've gone 1x11 on both FS mountain bike, Fat bike, and my wife's HT.

Good affordable option is the SLX shifter and RD with a Sunrace 11 speed cassette. I find 11-46 cassette is all I ever need for mountain biking.

I never really hated front derailleurs, but now that wide range cassettes are available, I just don't see the point of 2x on my MTBs.

To be a bit more specific I'm mostly trying to pin down weight differences between 1x and 2x. I've ridden 1x on several different bikes and know I would be satisfied with it from a riding perspective.

I'll guess about a half pound to one pound.

weight in total is one thing and weight distribution is another.

If you were going for a light as possible and best possible weight distributed build, you’d be looking at putting together a 4-7x2 drivetrain.

I don’t know if you can still source a freehub that’s both robust enough for how you intend on riding and is optimized for less than 8 cogs.

The industry isn’t there right now. If you can be satisfied with 1x and never need/want a granny/bailout gear, just do 1x.

Or do the mullet or reverse-mullet (I’m not cool enough to know which it is. I think it’s dumb to not call it extended range 2x): 1x rear + 2x front with whatever ring you would be comfy using for the middle four cogs 90% of the time and a bailout ring.

When i get around to it, im converting an old Marin rigid bike i have to 1x . Its their old Tange Prestige Team frame so a little effort and expense is worth it to me. Im using circa 2015 XTr derailleur and 11-40 11 speed cassette . I pulled this setup off my full squish daily driver when i switched to Eagle 12 speed on it and ithe parts have just been sitting in a box doing nothing

i recall weighing the cassette when i got it and it was close to a 200 gram difference compared to a cheaper steel 10 speed cassette —. That was huge- and 11-40 is PLENTY of gear for a 1x 26’er (was originally on a 29er)

And i have a XO-1 SRAM carbon crank with a 30t chainring i weighed recently, it was 475 grams. I weighed the xtr derailleur years ago and recall it was lighter than an equivalent Deore long cage i had laying around, but not earth shattering like the cassette and crankset difference. A triple chainring mtb setup can weigh well over 700g, so theoretically over a triple with a cheap cassette, im saving almost a pound using a carbon crank and xtr cassette, — then deduct a little more for front shifter and derailleur

it wouldnt shock me if you saved 2 pounds over a 3x setup with careful parts selection

I think it largely comes down to the weight of the cassette you use. The additional cogs being added are the largest ones, ranging from 42t-51t. How those are added makes a difference.

When I was looking at different options for an 11sp, 11-46t cassette, the difference in weight between the high and low end cassettes was pretty big. More so than when I was looking at 9sp 11-34t cassettes.

^^^ that's because of SRAM's single-piece cassette, Shimano's titanium, and the other tricks being played at the high end. But they are expen$ive.

The least expensive cassettes are a stack of cogs and spacers all stamped out of sheet metal. The mid range ones have stamped cogs riveted to aluminum spiders.

The power dome ones are a single piece. Here's a pic I found via Bikerumor of a SRAM power dome cassette that broke. The stack is all machined from a single forging, and it's a forging just for this, not a "block" or bar stock. You can see the same if you look in the back of an XX1 cassette, except with the bigger shifts and cogs there's even more empty space. This is not cheap for them to make and the price tag is appropriate. Aside from weight this has other advantages - it's pretty hard to "fold" this cassette like the cheaper ones because there's just not a big flat piece that can fold, and the normal deflection you might get short of actual damage is also better withstood which is probably going to improve shifting.

I'm not so sure about Shimano's XTR titanium, which does not seem like it should cost so much as it does given that it's only different material, not style than XT, and probably still stamped.

To use one of these SRAM cassettes you also need a SRAM freehub, which also (not always but almost always on a MTB) means thru axle and disc brakes.

https://cimg7.ibsrv.net/gimg/bikefor...03cfbcc11f.jpg

We just did this on two bikes. It is solid.

On one, we (well, the kid) replaced 12-speed with Microshift Advent X 10-speed. He has been through two GX Eagle derailleurs, then shifted over to Shimano, and went through an XT and then SLX 12-speed derailleur. We decided to cut our losses, and he is perfectly happy with the Advent X 10-speed on his Stumpjumper Evo.

The other was converted with Advent 9-speed, for my wife. It is a 26" bike and also works fine (replaced original XT).

Hmm, more support for Microshift. How does it compare to, say, SRAM? I rode a brand new bike with NX 1x11 and was predictably disappointed with it. Typical SRAM higher effort and less precision than I'm used to. I don't have any vivid memories of using Shimano systems made within the last 10+ years but can't recall anything that matches the feel and crisp shifting of my old 8-speed stuff (yes, seriously.)

I have NX, XT, and SLX 1x11 speed, all with Sunrace cassettes. Honestly, they all work fine for me, they just feel different in the shifter. Push or pull a lever, they shift. The Shimanos feel more crisp and precise at the shifter, but they don't shift any more reliably or faster than the NX. I like the ergonomics of the SRAM shifter a little better.

And none of these shift any better than literally any other rear shifting I have owned for the past 20 years. Main thing I notice is that 11 speed seems more picky about having a perfectly straight RD hangar.

Our (his) experience with 12-speed: SRAM GX Eagle was unusable and self-destructed. Twice. Went through 2 derailleurs quickly. XT was vastly better, but Shimano's clutch is poorly designed (and is a $10 consumable part). The SLX is nearly identical functionally to the XT, including the clutch. All 12-speeds appear to be very fragile, so the next experiment is the Microshift Advent X drivetrain. So far, it is flawless, and the kid doesn't miss the extra speeds. Their clutch has a vastly better design, FWIW.

My personal very biased opinion is SRAM makes garbage brakes and components, at least at the GX level. I won't ever buy a bike again with SRAM on it.

Video review:

how about my 1x 7...
works great fun simple
https://cimg0.ibsrv.net/gimg/bikefor...a94d5800c2.jpg
see the large swans..

I went through this exercise once, where I actually weighed everything, but don't remember the numbers.

When all was said and done the extra weight of the few extra cogs on the cassette for the 1x system was less than the weight of the 2x system. Shifter, cable, derailleur, chainring and chainring bolts add up to more weight then the few extra cogs on the cassette. Plus 1x is less to maintain.

1x for the win all day long.

My understanding was that a 1x was usually about a pound lighter, much more reliable, and slightly more efficient as long as you are able to get a wide range of gears on the rear cassete.