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How would I go about changing my 3x to a 1x drivetrain? Can I simply buy a (104 BCD) narrow-wide chainring and mount it up with some chainring bolts, or is there more to it? Do I need some sort of conversion kit?


I have an SR Suntour XCR-6 crankset, if that matters. Thanks
 

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Microshift advent is 1x9 groupset with 11-42 and 11-46 cassette. But you need to buy a chain from other brand. So you choose a chainring nw 104bcd (I recommend 30t for steep climb) and whatever chain you want just 9 speed.
 

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If you don’t increase the range of the rear cassette, you won’t really be improving the bike much by removing the front gears. On the other hand, if you improve the range on the rear, you could easily just ride the middle chainring to effectively have a 1x.
Put another way, except for a minor weight savings, the greatest benefit of a 1x is the wide range of rear gears.
Increasing the range of the rear will depend on the capacity of your rear mech to fit larger gears (like 40+teeth) which you may be able to increase if necessary with an extender.
 

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Technically you could just lock out your front derailleur on the middle chainring and you've got a 1x9, but your cassette is probably somewhere around 11-34 so you'll take a big hit when it comes to your ability to climb.

As others have said a 1x system uses a wide range cassette, anything up to 10-52 with the latest offerings from SRAM.

I've actually done two 3x to 1x conversions now, for my MTB I went with 11 speed XT for the shifter and mech, a OneUp Components narrow-wide chainring, a Wolftooth Components Goat Link and a Sunrace 11-50 cassette.

For my flat bar to drop bar gravel bike conversion I opted for the Microshift Advent X which uses an 11-48 cassette, and is available with both a flat bar trigger shifter, and drop bar brifters. Most of the time I run it with a 42T chainring, but for bike packing trips I swap the 42 for a 34 to give me a lot more climbing ability.
 

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I read that the chain rings are fused on your crank model. If not, then you can add a NW chain ring.
This is definitely something to check. My MTB conversion had a bolted crankset, so I could just buy the relevant chainring. My drop bar donor bike had a riveted crankset on a square taper, so I ended up with a new crankset and BB.
 

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I did a little gear ratio math on my bike and went from 3x9 (22-32-44x11-32) to 2x9 (22-36-bash ringx11-36). I felt like I eliminated the ridiculously high gears that I liked to use once in a while.
If you do the math and go 1x9 on your ride, you will want a bigger range on your cassette-->different shifter-->bigger range on derailleur...

-F
 

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If it's a 26er I'd leave it 3x, a 32t front on 26 is not fast enough, my 26er 'shed bike' is staying 3x. 29er 1x9 works great, I did a 30t on my hardtail, I would have done 32 but I consider it my 'mud' race bike and a little lower gear is nice, I have a 32 front on my fs 'dry' race bike. The 30t is working well (cheap Snail brand wnw ring off ebay, the snail is pretty cool, the 30t is threaded so you only need the screw part of the chainring bolts, and it's a little bit offset for the chainline). I did a Sunrace 11-40 cassette on that bike, your derailleur may or may not support that, - the sunrace has been a good cassette on my bike.
 

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What is the bike you are attempting to make the change on and what is the stock rear derailleur?

I successfully converted a standard range (11-34T) 1x8 setup to a widerange (11-40T) 1x8 using the stock SRAM X5 rear derailleur and a Wolftooth Goat Link. I rode the bike that way for years.

It does appear the XCR-6 crankset is bolted, if the image below is the similar to what you have. In that case, the narrow wide chainrings from Snail/JG bike on Amazon should work just fine.


If you want to upgrade the rest of the drivetrain for a wider range, I would take a look at the Acolyte, Advent and Advent X line from Microshift. They are very reasonably priced and perform quite well.
 

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Need specifics on bike and existing setup but you should be able to do it.

About 3 years ago I did a 1X9 conversion on my 2012 SC Heckler. Before doing anything I spent the time to figure out that a 30T chain ring combined with an 11-34 9spd cassette would work for my trails. Also ran various gear ratios into a gear calculator to compare existing 3X ratios with proposed 1X9 to verify I would be in the range I needed.

Stayed reasonable cost-wise using shimano XT components (M770 9spd cassette and 'shadow' rear der) along with a Zee M6 crankset that fit my bottom brkt design. I had to buy a 30T chainring that would fit the Zee bolt pattern because it came with 34T. You can still get these parts on-line.
 

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I’ve converted three bikes to 1x in a month. You just match the parts to the goal/funds.
mine I replaced 3x xt in a very old 110x5 pattern with a quality (saint) bottom bracket and generic aluminum cranks. I chose the crank length and 1x size based on my preferpence (175mm, 32T). Used Adventx cassette shifter and derailleur and a new 11 speed chain. Total cost $300.
daughter 1 i reused the 94 bcd 5 arm cranks and sq taper bb from the 3x, put a 30t on it, and used the 9 speed advent 42 cassette, derailleur and shifter and a 10 speed chain. $175.
daughter 2 has 24” wheels And had a riveted 152mm 3x. That required a 152mm 3x 94bcd crankset from sun tour, which I discarded the chainrings and replaced with a 30t, and put on a new 8 speed chain. The 34t megarange on a 24” wheel with a 30t is only 3 gear inches more than the 42/30 on a 26”. Dropped the gripshift with a 7 speed shimano rapid fire. $100.
 

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Yes, you can just remove the two other rings, the FD, and replace the middle with a Narrow-Wide ring. Then shorten the chain. No need for a new crankset.

One thing I might suggest is instead of getting shorter chainring bolts, get a BBG BashGaurd for the outer ring.position (google it) They are about $20 shipped. It will help with chain retention, since you don’t have a clutch RD.

There are in fact several benefits to losing the big and small ring.

Losing the big ring lets you run a shorter chain, as the middle position is now the “big” ring. This is why I used to convert all my 3x cranks to 2x long before 2x was offered stock.

Taking the next step of losing the small ring lets tou lose the FD (obviously) but also has the advantage of letting you run a NW ring.

Keep in mind you don’t have to go 32t for the single ring. There are NW rings out there that come in 30t that will work with your 104BCD middle position. There are also 28t rings that mount to your small ring position that are offset to move the ring closer to the middle position.

I’ve always found 32t ring with an 11t small cog to be perfectly fine as a high gear on 26” MTBs. The times I spin out are rare, and mostly just on the pavement or relatively smooth dirt road. The real question is whether you will have low enough gearing, but I assume you have already determined that you will.
 

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If it's a 26er I'd leave it 3x, a 32t front on 26 is not fast enough
Where's the fire? I'm running 30 x 11, and the only time I wish for a higher gear is if I'm doing a loop that finishes with a paved descent, but I really don't care if it takes me five minutes longer to get home. But of course, for some people, speed is part of the fun, so YMMV.

The 30t is working well (cheap Snail brand wnw ring off ebay, the snail is pretty cool, the 30t is threaded so you only need the screw part of the chainring bolts, and it's a little bit offset for the chainline). I did a Sunrace 11-40 cassette on that bike, your derailleur may or may not support that, - the sunrace has been a good cassette on my bike.
Remarkably similar to my setup. Snail came recommended, and was cheap, and I love the whimsical snail icon. The 30T not only lowered my first gear a smidge, it also moved my chainline closer to where I wanted it. Anyway, with an extension link, I'm running 44T on original derailleur. Very little $ invested.
 
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