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^ Thanks for posting that; More evidence that DynaSys cable travel is the same as SRAM 9 speed. :)
Hi Satanas,
does it mean that you suggest that I can change my 9sp SRAM X9 RD with Shimano XT/SLX Dynasys10sp RD without changing my 9sp X9 shifter.?
 

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Tnks for all the info in this post, just something i dont understand.
Can i use a new xtr m980 28-36 crankset, with all my m970 setup?
- cassette 11-32
- fd and rd
- dual shifters
- kmc x9 sl gold ti

I really like the great lookin of the m980 crankset.
 

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Tnks for your answer Frank, but putting the Correct limits in the actual fd should work? Or is really necessary the change?
The chain isnt a problem.
 

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38/26 t M980 XTR Chainrings on M970 XTR Cranks

Hey, I was thinking abo ut doing the same upgrade (a 10sp xtr crank on an otherwise 9 drivetrain) but my lbs has just told me they could never get a 10 sp chain shift well over the 9 cassete.
I understand the need for a 10 sp fr deraill. But is the 10 sp chain a must?
Cheers
--------------------------------------------------------------------------------

Just finished converting my 2007 FC-M970 Crankset 44/32/24 to 38/26 using FC-M980 Chainrings !

Parts Purchased ;

FC-M980 38T-AH Chainring part # Y1LR98030
FC-M980 26T-AH Chainring part # Y1LR26000
FC-M800 FIX Bolts Part # Y1FB98010 only used 4 mm spacer from kit.

M970 Chainring thickness 1.96mm
M980 Chainring thickness 1.88mm this is only .0003 " not any differance !

I mounted the 38t using the stock lenght M970 XTR bolts and placed the above chainrings spacer under the head to fill the gap left by the removal of thhe 44 t large chainring this has a 4 mm thickness were the bolt goes throught the chainring, then mounted the 26 tooth chainring.

The M980 26t chainring has the exact same offset as the M970 22 or 24t Chainrings (2.1mm) Used my M970 XTR shifter and FD-970 XTR front Derailleur with only a small height adjustment. Just got back from a quick test ride and shifts great maybe a little smoother !

The small to middle spacing is exactly the same !

Weights 38t-79 grams / 26t -36 grams / qty Alum 4mm Spacers 2 grams for a total of 117 grams, M970 44/32/24= 156 grams / 44/32/22 = 148 grams so I saved 39 grams !

Pictures to follow left my camera at work. Very easy 2x9 conversion with a little research for the right spacers, I tried to fine shorter bolts however I was not able to fine the short female side that would be required. I think the stock M980 FIX bolts would work exept they were $$$ 68.00 for the set !

Still Using all the rest og my M970 XTR drive train RD-M970 and chain !
__________________
 

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Spin cycle, so you think that if i use the m980 26 -38 crankset, with all my m970 stuff, will work? Just setting the limits of the fd and maybe using a spavcer?
 

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Spin cycle, so you think that if i use the m980 26 -38 crankset, with all my m970 stuff, will work? Just setting the limits of the fd and maybe using a spavcer?
I measured everything before and after and the spacing between the chain rings is the same, as I posted the differance in the chain ring thickness is .003 if an inch ! Just got back from a 2 hour ride and no problems. I spent a good amount of time with it on the stands setting the height of my front derailluer (FD-970 low mount) currently set at 3 mm above the 38 t ring and shifting great. I should add that I all waays have run my chain line at 46.5 mm not the standard 50mm that is the stock set up for FC-M970 crank set, I just removed the center dust tube and run a .7mm spacer on the drive side and a 2.5 & .7mm on the non drive side this moved the chain ring into the frame 3.5 mm. Then add a 2 mm pedal spacer to equal it out at the pedals.

The key is to buy the FC-800 chain ring bolts to get the 4.0 mm spacer unless you can find some really short female side bolts to mount the middle ring. It works better that I ever thought. PM me if you want .
 

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Hello from Australia and a question...

Hello everyone, first time on this site and I need some advice. I have decided to step out of my comfort zone and build a mountain bike. I am working on a Baum Titanium hardtail frame, medium size. I am up to the stage of trying to work out what size crankset to buy. After reading through some of the information on the posts I have established when it is stated 175mm that refers to crank arm length. I am 185 cms tall, so what length would you advise? Next question relates to bottom bracket. Does the length and width of bottom brackets vary or is it standard sizing for all mountain bikes. I am concerned that if I purchase a bottom bracket off the net, then I could be in the position of purchasing the incorrect size. If I need to get a particular size how would I determine the sizing. I know I sound like I do not know what I am doing, and you are right, but I guess that there is only one way to learn and that is from the hip pocket. I look forward to using this site for regular technical advice and if any of you guys are ever plan on coming out to OZ, please let me know as I am looking for someone to go riding with, cheers Ian

This is what I am looking to purchase:
Race Face Evolve Crankset SS 175mm
Arms are net shape forged from high strength 6066 aluminum to maximize strength to weight ratio. All-Mountain strength at XC weight.
High wearing 7075 aluminum chainrings feature extensive CNC machining for shifting accuracy and sharp looks.
Evolve cranksets feature our 'EXI' interface external bottom bracket system for easier crank installation and removal with standard tools and fully adjustable chainline.
Features the lightweight, forged and CNC machined CrMo steel EXI spindle.
Bearings feature our custom triple wiper seal to better retain grease & keep contaminants out.
Comes with the all new Race XC BB
Bearings are factory filled with Phil Wood waterproof grease - tested & proven to extend bearing life.
 

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meow, meow.
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ianjames9373,

I'd go with 175 mm cranks.

As for BB size, RF EXI type cranksets can be installed out of the box on 68 and 73 mm BB shells. Measure BB shell width on your frame, it is likely 68 or 73 mm. Also verify that the threads are English standard (left hand thread at the right side, right hand thread on the left side).
 

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ok i have been out of the biking scene for a while and notice this 10 speed set ups now. i have tried to read through this whole thread but just looking for some quick answer. i have a 9 speed set up right now. and planning to get a new bike with a 10 speed drive train. all i want to swap from my 9 speed to me 10 speed is my 26/36/48 crankset will this cranset be compatible with the 10 speed set up?
 

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Team U.G.L.Y.
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No. I've been down this path and it wasn't pretty. 1st I tried just running my same old 2x9 Dues XC crankset and the new 10 speed chain would get stuck in between the rings and not seat properly on the teeth. 2nd I tried changing to 10 speed rings and keeping the cranks, this just made the chain getting stuck between the rings worse. Chainring washers didn't help, because it weakened the rings and allowed them to flex. 3rd I ordered an X9 2x10 crank and F. derailleur, mounted it, and now I ride with no issues and a stiffer more direct crankset.

Don't make the mistakes I did. Just get a complete 10 speed drivetrain.
 

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the catalan connection
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My own kind dyna-sys

I decided to get rid of the TOO large 44 outer on my crankset. Got a 40 outer and also thought that would´t hurt to have the same tooth diff from the small to the 32 middle so also got a 24 small. Now the drivetrain is 24-32-40. Pretty much like a dyna-sys. Note there is always a 8 teeth jump from either ring. Feels nicer. All drivetrain is 9 speed.Also got a 11-34 cogset to compensate the larger 24 granny.
The problem came when I tried to adjust the front derailleur.(still a 9sp low clamp XTR) There was no way to get it right. Since the larger ring was way smaller I had to move the derailleur down, but then the inner cage would jam with the middle chainring. That forced me to leave the derailleur way upper than I liked and shifting was never good. But looking closer I found that a derailleur with a less tall inner cage would clear the middle ring just fine and started looking for it. I went to the LBS and started checking different derailleurs. All looked more or less like have the same problem.Then I got a XTR 10 sp dyna-sys on my hands, placed on the bike and was looking like it would clear it. Went home, installed it and...voilà! Shifts perfect (remember I use 9 sp shifters, xtr), it doesn´t rub in any combo, it drops to the small instantly (also a problem to solve with the low-clamp 9sp xtr I had before) Instant and crisp shifts. I really mean it when I say is the best adjusted derailleur I had in my 18 years of riding.
I don´t know if it would perform tha same on a normal 22-32-44 crankset, I dunno it. But if you go the same route of trying to make your own kind of dyna-sys crankset is definitely the way to go.
 

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so what is the answer here.

I have a 3x10 system (24,32,42) with 11-36.

I want to change this to 2x10 w/bash (racefacelight bash) (24, 36) 11-36.

What 36T chainring would be best for this?
 

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Because in order to improve the reliability of the mtb 10 speed shifting, shimano has finally admitted to themselves that SRAM had the right idea lowering the leverage ratio of the rear derailleur cable pull geometry (which makes the derailleur less sensitive to cable stretch and tension changes from shifter housing movement on a rear suspension bike). So the shifters now pull more cable than before for each shift. SRAM's 10 speed shifters and derailleurs also pull more cable than their 9 speed units. I believe the SRAM 10 speed works out as a 0.8:1 ratio now, their 8/9 speed stuff is 1:1, all shimano derailleurs except the new 10speed mtb (and the 7/8 speed DuraAce) are 2:1 and the shimano 10s MTB is I believe its been measured out as something like 1.25:1.
I know I'm dragging up an old post here, but from what you're saying, in theory you can set up a 10 speed system using the new xt/xtr front shifters with the old xo 9 speed rear mech & a 10 speed cassette.
 

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I know I'm dragging up an old post here, but from what you're saying, in theory you can set up a 10 speed system using the new xt/xtr front shifters with the old xo 9 speed rear mech & a 10 speed cassette.
I've just re-read the whole thread and based on what people tried and reported, 9sp SRAM rear ders are in fact interchangeable with 10sp Dyna-Sys units.
 

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Read the whole thing as well....but couldn't find the answer to my question. Will the SRAM 10 speed chain(s) and cassette(s) work with the Shimano Dyna-Sys 10 speed RD (1x10 setup)?
 

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Rider and Wrench
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Read the whole thing as well....but couldn't find the answer to my question. Will the SRAM 10 speed chain(s) and cassette(s) work with the Shimano Dyna-Sys 10 speed RD? Can't exactly figure out how and why EXACTLY the Shimano chains are directional...? I know it's for "the bestest shifting in the galaxy", but thats about it.
You should not run into any issue using the XT Dyna RD- the special profile/directional chain only affects the outside of the chain_
 
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