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Discussion Starter · #1 ·
2014 Trek Superfly 9.8 with 38/24

Last year I ran a 1x with 32f & 11/32r

I am not happy/used to large jumps in gearing with 38 & 11/36

What are my options?
Can I run 2x with 24 granny and smaller big ring (32? race face, etc?)

If I went back to 1x, can I simply bolt on race face 32t in place of 38t?
 

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Assuming your crank has a 104 BCD, yes. Could even put the 30T ring on if you don't mine loosing the top end. Would make a 32 rear cog more manageable.
 

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Again, assuming a 104/64 BCD you should have no problems. Technically you should match the 2 rings, buy them as a pair, so the ramps etc line up.
 

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Discussion Starter · #5 ·
Slash, Thanks for your response

With my front Derailleur fd-m786, Shimano says Top Gear Teeth 44-38T.

Has anyone used anything smaller than 38 for big ring on 2x?
 

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I'm using a 22 and 34T set from Blackspire and they work very well.
 

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Ronnie, just to confirm, you installed 22T and 34T chain rings on your XT 785 cranks? I only ask because I was completely unaware that this was possible. Sounds perfect for me!
 

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Ronnie, just to confirm, you installed 22T and 34T chain rings on your XT 785 cranks? I only ask because I was completely unaware that this was possible. Sounds perfect for me!
I've actually got a Shimano FC-M770 (three ring) crankset. I've got 22/34/bashguard fitted. It has the same 64mm. and 104mm. BCD as the M785. According to Blackspire on the page I linked above:

"● 22-28t & 34-40t rings are compatible with Shimano M785 and M675"

I started using the Blackspire rings a few years ago when I wanted replacement rings for a XTR M960 crankset I have and they still shift flawlessly. Also 22/34T.
 

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Discussion Starter · #9 ·
Ronnie, just to confirm, you installed 22T and 34T chain rings on your XT 785 cranks? I only ask because I was completely unaware that this was possible. Sounds perfect for me!
While i was Doing rsearch on this i came across service bulletin from one of the chainring manufactuters Wolftooth (FOR THEIR 1x) that u could put a 32 on, but had to space out sprocket 2mm or grind a little of crank to get chain to not hit crank
 

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Do u think i could just get away with big ring? And keep shimano granny?
In all probability it would work fine. The Blackspire 22T ring has no ramps or pins and looks very much like the original Shimano.

CRsuperPROmtb22_b.jpg
 

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The Bubble Wrap Hysteria
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I've actually got a Shimano FC-M770 (three ring) crankset. I've got 22/34/bashguard fitted. It has the same 64mm. and 104mm. BCD as the M785. According to Blackspire on the page I linked above:

"● 22-28t & 34-40t rings are compatible with Shimano M785 and M675"

I started using the Blackspire rings a few years ago when I wanted replacement rings for a XTR M960 crankset I have and they still shift flawlessly. Also 22/34T.
I have the similar set but 24/32 w/bash guard and a 11-36 rear. It works flawlessly.
 

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Discussion Starter · #20 ·
I mounted 32t Blackspire chainring last nite and going to 32t on rear (big to big) (11-32 casette) there appears to be cross chaining(?) from front sprocket that you can feel in pedal on work stand (throbbing)- shift to next gear higher (28) and it is fine.

It does have a clutch derailleur. I thought I measured chain like I usually do - rear derailleur angle seems ok. I may try adding a link later - see if that makes a difference

Any one experience anything similar?
 
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