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Converting 3x9 to 2x9

1504 Views 13 Replies 11 Participants Last post by  tmcq
I've always wanted to give myself different gearing options and have been thinking about converting the standard 3x9 gearing setup on my Niner Air 9 to a 2x9 using a 28 and 42 ring instead of an 22,32,44. The problem is I don't even know where to get started. Do I need a special crankset or front Derailleur, or is it possible to space the rings out evenly on my existing crankset?
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Yep just get the rings you need, put the big one in the middle ring place, then the small in the small ring place. Adjust your limiter screws so it won't go passed the outer ring. and ride!
No special cankset or deraileur needed. If you need rings have a look here.
Those rings may not fit though depends on which cranks you have, they fit most cranks though.

EDIT: Just remembered, you'll need some shorter bolts for the outer ring. Have a look at problemsolvers or middleburn.
You might not need shorter bolts if you put a bash guard in the large ring spot.
Using a standard 104/64 Race Face Deus crank with chainline adjusted as far right as possible, I could only do 26/36 rings on my 09 Niner Air 9...The 36 just barely misses the chainstay. I have a tube wrapped around the stay for chainslap protection and the 36T rubs it...Running a SRAM Force front mech with a speen adapter and have no issues shifting and can cross chain little and big ring with no rubbing......
I'm running a 2x9 on my 3x9 Stylo cranks. I put a bash on the big ring and left the 22/32 rings. Neat thing my shop did was to keep the third derailleur setting and I use it like a trim tab for adjusting the small ring so it doesn't rub, works pretty well.
2x9 rear derailleur?

Will a medium or even short cage rear derailleur work with a 2x9 set up?
Medium cage is typically ideal, with a short cage you may not be able to shift into small cog and and small chainring this is all depending on your chainring size differences and the size of your biggest cog
idon'tknow said:
Will a medium or even short cage rear derailleur work with a 2x9 set up?
A medium will for sure, but a short cage depends on what size rings and cassette your using.
A good rule of thumb I read on here was for 3 rings use a long cage, for 2 use a medium, and for 1 use a short.
Converted my XT hollowtech crankset to a 2x9 last night on my On One Scandal 29er. So the gearing is currently 44/32, would love to take it to 42/29 even 42/28. What I did was just removed my 22 granny gear and removed one spacer on the BB to get a better chain line. Also no need for shorter bolts. Problem is do one get a 29 ring for a XT crankset that sits on the middle?
Hi, I intend to setup my bike for commuting purpose. So I intend to change it to 48/32.

May I know if it is possible? and do i need to get a front d'railleur?
kiatkiat said:
Hi, I intend to setup my bike for commuting purpose. So I intend to change it to 48/32.

May I know if it is possible? and do i need to get a front d'railleur?
I don't see any reason why it wouldn't work.
You may need to get a road front derailleur. On the sram website it says the X-9's top gear is 44t/48t, but on the shimano website it says 44t.
I think Shimano can still handle 48t. The trekking group set are using mtb d'raileur.

But the problem is dunno if it can handle the 32t to 48t huge gap.
_daemon_ said:
Converted my XT hollowtech crankset to a 2x9 last night on my On One Scandal 29er. So the gearing is currently 44/32, would love to take it to 42/29 even 42/28. What I did was just removed my 22 granny gear and removed one spacer on the BB to get a better chain line. Also no need for shorter bolts. Problem is do one get a 29 ring for a XT crankset that sits on the middle?
The closest you are going to get that I know of is the extralite 30t middle ring. I've heard that some filing is needed to get it to fit and shift right. My suggestion would be to check out the link earlier in the post and get a 28t or 30t to fit on the granny gear and put the spacer back on the bottom bracket.
Can I go 1 X 9 Without buying a new crank?

I have been wanting to convert to 1 X 9 and assumed I would have to buy a new crank. I currently have a 22-32-42 and I never use the small chainring. I only use the middle chainring to get to the lowest sprockets on the cassette since the big - big chainline is at too sharp an angle for reliable shifting. While I would like to put my 42 into the middle position and be done with it...it is too big and would grind into the stay. I would like, then, to get a 38 tooth middle ring to use as the only ring. Can I install a chainguide like an e-thirteen or MRP and a bashguard with my "partially filled" existing crank?
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