[FaithRaven]

Could someone please tell me if 9speed FD will work with 10 speed shifter & cranks. All mtb.

 

[ryguy135]

Looking for some Info!
I am wanting to run a set of 2012 Sram XO 2x10 Cranks with a Sram XO 9 Speed Redwin rear Derailleur.
I am currently running a Sram Pg 1050 / 12-36T Cassette, and a Sram X7 2x10 High Mount Front Derailleur. I am also changing the front shifter to a Sram X7 2x10 from a Sram X7 3x10 shifter.
Can I run these cranks with that derailleur? Can this work, and if so what else might I have to change or do to make this setup work?

Nope. You'll need a 10 speed rear derailleur. SRAM changed the pull ratios slightly so you can't use a 9 speed derailleur with a 10 speed shifter for a 10 speed setup. However, you could use a Shimano 10 speed rear derailleur. Dynays's 10 speed pull ratio does work with SRAM's 9 speed derailleurs for a 10 speed setup.

 

[ryguy135]

Could someone please tell me if 9speed FD will work with 10 speed shifter & cranks. All mtb.

Will work just fine.

 

[Jeepnut22]

Updating cranks & chain only...

Current setup:
2007 XT 3x10 cranks, converted to 24x36 2 ring.
9 Spd FD and shifter
9 Spd RD and shifter
9 Spd 11-34 cassette
9 Spd SRAM 981 chain

Planning stetup:
2011 XT 2x10 cranks, 26x38
Keeping - 9 Spd FD and shifter
Keeping - 9 Spd RD and shifter
Keeping - 9 Spd 11-34 cassette
KMC X9-XL chain

Issues, things to consider? Thanks...

 

[Teigansdad]

The only possible problem you might run into will be if the X9 is indeed a 9 speed chain. You might possibly run into some trouble while in the 26t ring up front. This could range from chain rub and cross chaining to the chain skipping from time to time if the wider diameter chain gets picked up by the shifting ramps. Could try it, and report back or simply go with a 10sp chain which would be my recommendation. I run a 10sp compact and 10sp chain with 9 speed shifters, fd, rd and cassette on my road bike with no problem. If you are looking for reference check out the sheldon brown website. He talks all about chain size

 

[Jeepnut22]

^^ Sweet, thanks!

 

[gadget1]

@jeepnut

My understanding is for optimum performance you need a 10 speed front derailleur and front shifter with the 10 speed cranks. this is because the front chainrings on the 10 speed crank are marginally closer together than on the 9 speed cranks. what you are proposing should work, but possibly not be ideal.

and yes, you'd probably want to go with the 10 speed chain.

I recommend the shimano 10 speed chain with a wipperman 10 speed chainlink for easy removal/cleaning duties.

 

[gadget1]

though according to point 4 on the first post on this thread, you may be able to keep your 9 speed front shifter when using 10 speed front derailleur and crank. But i always thought it best to keep the front the same and the rear the same.

Am i right that the spacing on the front chainrings is different for 9 and 10 speed cranks because the chainrings themseves look interchangable.

Has anyone had any problems when they've tried just swapping the chainrings over from 9 to 10 speed cranks?

 

[Jeepnut22]

@jeepnut

My understanding is for optimum performance you need a 10 speed front derailleur and front shifter with the 10 speed cranks. this is because the front chainrings on the 10 speed crank are marginally closer together than on the 9 speed cranks. what you are proposing should work, but possibly not be ideal.

and yes, you'd probably want to go with the 10 speed chain.

I recommend the shimano 10 speed chain with a wipperman 10 speed chainlink for easy removal/cleaning duties.

Thanks! Think I am definitely going to exchange my 9 speed chain for a 10 speed chain. Gonna see how the 9 spd FD and Shifter work out. I'll report back!

 

[Teigansdad]

Thanks! Think I am definitely going to exchange my 9 speed chain for a 10 speed chain. Gonna see how the 9 spd FD and Shifter work out. I'll report back!

I think you're right to give it a go. Especially as you are running a compact up front. I would wager the worst case scenario will be how much you have to trim your inner and outer travel limit. My guess is if there is a compatibility issue it would be more likely to occur with a triple ring set up. For sure worth trying before you drop the change for front der and shifter. From my calculations that's a pair of tubeless ready tires and a bottle of stans.

 

[Teigansdad]

though according to point 4 on the first post on this thread, you may be able to keep your 9 speed front shifter when using 10 speed front derailleur and crank. But i always thought it best to keep the front the same and the rear the same.

Am i right that the spacing on the front chainrings is different for 9 and 10 speed cranks because the chainrings themseves look interchangable.

Has anyone had any problems when they've tried just swapping the chainrings over from 9 to 10 speed cranks?

I used 10s rings from blackspire on my slx 9 speed crankset. my setup: xt dynasys shifter, front and back, 9 sp xt front der. 9 s slx crank w/ 10s rings 38t and 24 t, 10s xtr chain, xt 10 s cassette and rear der. Raced all season, shifted flawless. Seemed like just a touch of cross-chaining related rub in the 38t front, 36 t rear gear combo...not enough to affect performance. I do wonder if the 10 s specific crankset would have a little better chain line to avoid this.

 

[DarkFly3r]

Anyone tried 10-speed crankset on a 9-speed drivetrain? Will it work? Thanks.

 

[stolegrom]

Maybe I missed...Is it possible that 10sp front der. works with 9sp chain, crankset is Slx FC-M665 36/22 ? Thank you!

 

[Jeepnut22]

Anyone tried 10-speed crankset on a 9-speed drivetrain? Will it work? Thanks.

That is exactly what I am trying. Installing this week and will know how it works next week sometime. I'll report back!

 

[DarkFly3r]

That is exactly what I am trying. Installing this week and will know how it works next week sometime. I'll report back!

Awesome! Keep me updated.

 

[DeeEight]

Not correct, the shimano 10 speed rear road derailleurs have a different parallelogram than the pull ratio for 9 speed mtb. You won't hit all your gears, especially in the middle of the range.

Bzzzzt Wrong !!! But thanks for playing.

Yes the parallelogram is different but the pull ratio is actually identical. The difference between all the eight to 10 speed shimano road and all the 9speed or less shimano mtb derailleurs (with the exception of the 7400 series dura-ace 8speed derailleur) was largely the angle that the parallelogram took as the derailleur shifted over, and how far down it then lowered the top pulley to track under increasing sizes of cogs.

That's why the road derailleurs maxed out at a 28T maximum cog size limit where the mtb models were 34T. And that's a conservative number at that. I've used the Ultegra 10 speed 6600 and 6700 derailleurs with 32T cog cassettes just by tightening the B-tension screw in all the way. The only shimano road rear derailleur that had a different cable pull ratio than any of the mtb models were the 7 and 8 speed Dura-Ace models which had ratios used by DA and nothing else. They weren't even compatible with the other road model groups of the same time period. When DA went to 9speed, they changed the pull geometry to match the other groups but made the rear derailleur ONLY backwards compatible for older DA owners by having a 2-position cable anchor bolt position. That way older DA owners could keep buying new rear derailleurs for as long as their pre-9sp DA shifters lasted, and the rest of the road line was still at the time 8 speed so replacement chain, cassette and chainring options were going to remain plentiful.

 

[JezV]

Hi all

I'm thinking of converting to 2 x 9 using my existing XT M770 crankset with 26/38/bash. Currently I have an XTR M970 FD but this won't fit my new frame so I need to buy a new one.

I could get a M971 high mount 9 speed and limit its travel as described elsewhere. However, somewhere I read that the triple FD needs to be set at the same height on the seat tube as it would be with triple rings, which makes it look very high when the big ring is taken away.

Would a M985 10 speed double work on a 9 speed setup and, if so, would it be a better bet? I gather it will work with the M970 shifter. I haven't bought the rings yet, so could fit 10 speed rings and chain if it would help.

Thanks

I haven't seen much mention of chain line in the thread above, but the M971 is designed for a 50mm chain line. Converting to double rings would effectively reduce the chain line to around 47.5mm. The M985 is designed for 48.8mm. Is 1.3mm within the bounds of adjustment?

I could suck it and see, but it could be an expensive mistake...

 

[NielsJ]

Hi all
I could get a M971 high mount 9 speed and limit its travel as described elsewhere. However, somewhere I read that the triple FD needs to be set at the same height on the seat tube as it would be with triple rings, which makes it look very high when the big ring is taken away.

I don't see why the height should be the same. The height should match the largest ring, but I don't know if the FD will interfere with the bashring. If so, the FD should be placed according to the basher.

I reused my 3spd FD for in my new 2x9 setup. No problems

 

[JezV]

I don't see why the height should be the same. The height should match the largest ring, but I don't know if the FD will interfere with the bashring. If so, the FD should be placed according to the basher.

I reused my 3spd FD for in my new 2x9 setup. No problems

Thanks NielsJ. Good to know

 

[coursemyhorse]

Thanks for all the info in this thread everyone. Very helpful.