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  1. #1
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    converting to 2x9 or 10

    I have been thoroughly enjoying my new ride (12' rockhopper comp 29er) except for the gearing. I ride areas here in socal with a lot of climbing. Ive been researching going to a 2x9/10 or even a 1x10. The bike currently have alvio shifters, acera front derailleur, and a deore shadow rd. My question to you guys is, for the average rider, what kind of gearing should I look for and should I look at upgrading my fd and rd? My reason for going to a 2x setup is that my bike never sees the road (never in the 44 tooth chain ring) and im usually in the granny gear. I also hear that cross chaining isnt as bad on the 2x set up. Any advise is appreciated!
    Thanks gents
    Rob

  2. #2
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    You say you don't like your gearing. What IS your gearing (what size rings, what range cassette)? What's wrong with it? Can't go high enough? Can't go low enough?
    15mm is a second-best solution to a problem that was already solved.

  3. #3
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    Quote Originally Posted by kapusta View Post
    You say you don't like your gearing. What IS your gearing (what size rings, what range cassette)? What's wrong with it? Can't go high enough? Can't go low enough?
    Its a 44/32/22 up front and a 11-34 rear. Its a little challenging getting up the steeper portion of the longest climb at my local trail. I'd say if it could be a tad lower as I continue to get better with my climbing skills I'd be happy. Then maybe sometime down the road when that gearing gets easy to climb with I will change it up. I've been thinking about doing a 30/20 up front.

  4. #4
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    Quote Originally Posted by vtwin650 View Post
    Its a 44/32/22 up front and a 11-34 rear. Its a little challenging getting up the steeper portion of the longest climb at my local trail. I'd say if it could be a tad lower as I continue to get better with my climbing skills I'd be happy. Then maybe sometime down the road when that gearing gets easy to climb with I will change it up. I've been thinking about doing a 30/20 up front.
    22/34 is a pretty low combo. If you need lower, I'd just give yourself some time to get stronger.

    Forget 1x if you want a gear as low as you have now.
    15mm is a second-best solution to a problem that was already solved.

  5. #5
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    Quote Originally Posted by kapusta View Post
    22/34 is a pretty low combo. If you need lower, I'd just give yourself some time to get stronger.

    Forget 1x if you want a gear as low as you have now.
    Will do. You are probably right. But on my second question about going to the 2x9. I really wont be using that 44 tooth ring as there aren't many flat runs that I go to. Should I hold off on removing it and going to 2x or would it be an ok move as a beginner to go ahead and remove it and get a new shifter? or even getting a little better group set?

  6. #6
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    Agree with Kapusta -- give yourself time to get stronger. I have 24/36 which isn't quite as low as 22/34, and I use it less and less.

    There is a point where lower gearing won't make it easier -- you have to go at least about 3 mph to keep from tipping over. Lower gearing won't allow you to climb slower. Climbing a long steep grade is tiring, no matter what gearing you have.

    As for your 3X to 2X conversion question, I did mine and like and like it a lot. I had 24/32/42 front 11/36 10-speed rear.

    At first I just removed the 42 ring. I got shorter bolts for the crank, but you could use washers. I adjusted the limit screw on my FD so it wouldn't shift past the middle ring. I also shortened the chain.

    There was a problem with this setup. If you were in a small cog in the back and the small ring in the front, then shifted to the 32 ring, the chain would walk off the outside of the big ring. This is because the top of the front derailleur cage was too far from the big ring.

    So I got a 2-speed front derailleur and all was well. If you replaced the big ring with a bash guard, that would work too.

    I eventually got a Raceface Turbine 24/36 ring set. I really like the feel of the gearing change when shifting between the large and small rings. The shifting is VERY smooth and fast -- almost as good as the rear.

    The larger big ring would probably have solved the problem of the chain walking off with the stock 3-speed derailleur.

    Let me know if any questions.

  7. #7
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    What about chain line? did you have to shim out the chainrings somehow to keep from cross chaining your 24/11 combo or isn't it really much of an issue for you? I'm thinking of doing this to my Stumpy but might try changing out chainrings on crankset a little.

  8. #8
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    yup 22x34 is plenty low for nearly anything sans a wall.

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    What about chain line?
    It is stock.

    All 20 combinations clear the FD cage, and I do not get a lot of noise in any combination. The noisiest surprisingly is large/large. 24/11, where you think the problem would be, is pretty quiet. Not that I get in that combo very often anyway.

    I get a pretty straight chainline in the gears I use most. When climbing, I am typically in the 2nd or 3rd or 4th largest cogs and small ring of course. When cruising over levelish stuff (nothing is actually level here) I am typically big up front and 3rd thru 5th or 6th in the back.

    While I am using 24/36 less, I do use it for really grueling steep stuff, and I prefer to have that optimized rather than higher gears.

    Look at it this way -- if you did shim it, you would go out only half of the distance between the rings, which ain't much. I'm guessing you wouldn't see much difference. And the longer chainstay length of 29ers help.

  10. #10
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    converting to 2x9 or 10

    I went through same thing with my 29er. i would go on sheldon brown site and check out gearing ratio. I did try the 20t chainring and worked. I went with dual because when on flats i liked the bigger chainring and then used smaller with all the hills. I wouldnt go with 1 x 10. U will find gearing is not easy enough i think. Use calculations on sheldons site. Again, i recommend the dual. Oh, make sure to shorten chain length as much as possible because that 20 is pretty small. I use njump to prevent chain sliding off. Works great! i think i got my 20t from actiontec because a lot of places dont sell that size.

  11. #11
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    There are several threads here about converting a 3x9 to 2x9. It is very easy, and very cheap to do.

    1- Replace the big ring with a bash ring. Check out BBG basguards for $18 shipped: Home you can re-use the Chainring bolts you have for this.

    2- Adjust the high limit screw on the front derailleur in to keep from shifting into what was the big ring.

    3- Shorten your chain. Follow Park Tool's instructions on how to determine chain length, except now your 32t ring it you "big" ring. Park Tool Co. ParkTool Blog Chain Length Sizing
    This last step is really key. Being able to run a shorter chain is probably the biggest benifit of going 2x. This greatly reduces the amount of chain slack when in the middle and small rings. Since you will actaully be using your "big/big" combo more often than before make sure you have enough bend in the chain around the pulleys, and ere on the side of too loose than too tight (you will understand when you read the directions).

    Regarding chain line, your chain line is actually pretty good already. Modern 3x cranks have their chainlines moved a tad outboard already, so 2x conversions using the small and middle positions work very well. You can use your 32 ring in all cogs, but I would not be running your small ring up past the middle of the cassette.

    You can try 20t grannies, dedicated 2x front deraileurs, etc, but I would do what I suggest above first, it only costs $18, and works like a charm for almost everyone that tries it. You can always stick on a 20t granny or 2x FD later if you feel the need.

    EDIT: One more thing is that you do NOT need a new shifter.
    Last edited by kapusta; 05-07-2013 at 07:26 AM.
    15mm is a second-best solution to a problem that was already solved.

  12. #12
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    converting to 2x9 or 10

    Oh, forgot to mention. if u go with 20, i would go with 32 or 34 for bigger chainring. You will find that both gears will overlap too much with 30 and 20. Again, u can see this using sheldons gear calculator. And use the 11/34 in rear like u already have. I think u will be very happy.

  13. #13
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    Great info, Kapusta! I'm just researching doing this and you answered all the questions I had.

    I'm looking forward to not only the extra clearance, but also to not getting stabbed in the calf by the big ring anymore!

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