1. The most important thing about buying a new bike is to make sure it fits. The only way you'll know if the bike is right for you is to size up the bike and make sure that the bike's geometry matches your body's geometry. Ask questions and do some research.
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2. If possible, try to find a shop that will let you demo the bike on real dirt. Five minutes in a parking lot won't cut it. You wouldn't buy a car without a real world test drive, and a bike should be no different.
3. Don't belive the hype. Just because your favorite rider or best friend rides a certain bike, that doesn't mean that's the best one for you. Have an open mind and be realistic about your needs and ability.
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  1. #1
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    Derailleur Education

    Was thinking about upgrades to my derailleurs and found out that there are dozens to choose from, of course. My main questions are:

    1. Medium Cage v. Long Cage Rear Derailleurs - What's the difference (other than cage length) and pros/cons of each.

    2. Low Clamp v. High Clamp Derailleurs - Again, what's the difference (other than the obvious construction types). Is it strictly a preference thing? Are low clamps designed to accomodate bikes with seat tube real-estate issues due to rear suspensions?

    Any other intel that I might not know to ask would be appreciated too.

  2. #2
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    With front deraillers you also have "top pull" versus "bottom pull". That difference is important. Which to get depends upon whether your derailler cable is routed down from the top-tube or up from under the bottom-bracket.

    Some front deraillers are dual-pull, and can be set up either way.

  3. #3
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    "1. Medium Cage v. Long Cage Rear Derailleurs - What's the difference (other than cage length) and pros/cons of each."

    The big difference is in the ability of the derailleur to take up the chain. A long cage is capable of taking up more chain than a short or medium cage. Thus it will have a larger capacity as far as gearing goes. General rule of thumb is if you are using a tipple front ring and a more or less standard mtb cassette, 11-32 or 11-34, use a long cage. If you are using a single ring up front (1x9) or a double ring and bashguard a medium cage is fine and in many cases prefereable.

    2. Low Clamp v. High Clamp Derailleurs - Again, what's the difference (other than the obvious construction types). Is it strictly a preference thing? Are low clamps designed to accomodate bikes with seat tube real-estate issues due to rear suspensions?

    This is an oldy and in some circles an issue of hot contention. In reality though the high clamp derailleur was the "oringinal" front derailleur design. It's a hold over from the days when road bikes were about the only thing available with multi gear transmissions. As far as performance there is little to be gained by going one way or the other. The low calmp came about as chainrings got smaller (compact drive) and there wasn't a need to lift the chain nearly as high from one ring to the next. Where you see them most commonly nowdays are on road bikes (still), FS bikes that have suspension clearance issues, and you'll see them speced occasionally on some hardtail mtbs for what ever reason. The one advantage of the low clamp design is, by placing the clamp lower on the seat tube it does give more latitude for clamp height adjustment without running into issues like waterbottle cage bolts getting in the way. This can be an issue with smaller frames and the high clamp derailleur design. There have also been some bikes produced in the past with externally butted seat tubes, why I really don't understand, but the transition from thinner to thicker tube made the high clamp impractical. Anyway the best bet is to stick with what came stock on your bike. The manufacturer likely speced the type for a reason, if nothing else than that's what they wanted. But in some cases (as rare as they are now days) there may well be a very good physical reason they did so. Usually though most modern mtbs will be speced with a low clamp unless there is some pressing reason to go with the high clamp. The only real reason to prefer one over the other is frame design/clearance issues.

    And we haven't even touched on E-type or the newer front d's that bolt directly to a swing arm or some other portion of the bike that some of the newer FS designs are using!

    Anyway, bottom line is, to be safe run with what was speced on the bike originally, especially with front derailleurs, unless you can test fit before hand. The only other reason to change designs would be if you are modifying the drive train, i.e. going 1x9 or 2x9 bashring setup, or something similar.

    Good Dirt
    "I do whatever my Rice Cripsies tell me to!"

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