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.
mtn. biking 101
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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    Is the plastic dust cover for the cassette important?

    I went for a ride today and noticed that the plastic cover behind the cassette was dislodged from it's normal position and when I got home I realized one of two plastic nipples holding it in place had broken off, therefore rendering the cover useless.

    I removed it from the bike so that it doesn't get in the way of my spokes, but would like to know if it's an important piece and whether to replace it or not.

  2. #2
    What could go wrong ...
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    nope ... its commonly called a dork disc for a reason
    I used to ride to Win ... Now I ride to Grin

    While my guitar gently weeps, my bike sits there mocking me

  3. #3
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    The upper limit adjustment on your rear derailleur keeps the chain from going off the largest rear gear and into the spokes. No real need for the plastic guard.

  4. #4
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    Ok cool, thanks guys!

  5. #5
    Workin for the weekend!
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    Quote Originally Posted by eb1888 View Post
    The upper limit adjustment on your rear derailleur keeps the chain from going off the largest rear gear and into the spokes. No real need for the plastic guard.
    Until your derailler comes out of adjustment, sending the chain over the top into the spokes... Just know what you're getting into before you take it off...

  6. #6
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    Quote Originally Posted by -Todd- View Post
    Until your derailler comes out of adjustment, sending the chain over the top into the spokes... Just know what you're getting into before you take it off...
    In that case, EVERYONE should get one put back on right away.

  7. #7
    gran jefe
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    Quote Originally Posted by -Todd- View Post
    Until your derailler comes out of adjustment, sending the chain over the top into the spokes...
    Wedging the chain in there, and bending/breaking spokes. One of those things that can save you some pretty serious trouble, but that many people get rid of.

  8. #8
    CSC
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    Quote Originally Posted by eb1888 View Post
    The upper limit adjustment on your rear derailleur keeps the chain from going off the largest rear gear and into the spokes. No real need for the plastic guard.
    True...though I have dealt with a crappy LBS upper limit setting on a loaner wheel...and became quite adept at fishing the chain out from the space between 1st gear and the hub (quite a task after the chain hops off during a steep climb...they really get wedged in there).

    I would think that a better, less "dorky" piece of hardware would have been made by now...maybe a disc of carbon fiber, with arms that lock onto the hub?

  9. #9
    Ride More, Whine Less
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    The plastic disc doesn't keep the chain out in the real world. The pressure from the cranks rips through the plastic like a hot knife through butter.

  10. #10
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    Sorry to jack but can that thing be broken off? (thus not needing to remove tha casette? Or does the dork disc removal require removing the casette?

  11. #11
    Ride More, Whine Less
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    Quote Originally Posted by ZmyDust View Post
    Sorry to jack but can that thing be broken off? (thus not needing to remove tha casette? Or does the dork disc removal require removing the casette?
    Yes. Cut it with a snips; it is plastic.

  12. #12
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    Interesting I didn't know that

  13. #13
    no trees are safe
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    I prefer to keep it. Screw looks, you never know what might happen on a bumpy ride.

  14. #14
    Ride More, Whine Less
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    When I broke mine on my first bike, I thought the world was coming to an end. 1000s of miles later, the world still turns without this plastic disk. Just make yourself a promise when the disk is old, yellow, and clunking around the hub as you pedal, that you will cut it out of the wheel.

  15. #15
    gran jefe
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    one time, when i was a young lad, first learning to adjust my limit screws, i went for a test ride and actually shifted the chain up onto the dork disk. i was really confused for a few seconds as to how i could pedal, and the chain could move, and i still wasn't going forward.

  16. #16
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    Just got my first bike, and mine is dislodged as well. It's used, so when I got home, I thought I got jipped. Good to know that all is well.

  17. #17
    T.W.O.
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    I took mine out but only because I couldn't handle the peer pressure

  18. #18
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    All the cool kids around here are replacing the DD with BBF's (big bright frisbees). It is the new bling! Y'all need to get you some!

    On a more serious note, I always wondered whaT that thing was supposed to do. Now I'm thinking of ripping mine off, because I've never had my chain go off that way.

  19. #19
    local trails rider
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    Quote Originally Posted by KingofWylieTX View Post
    Now I'm thinking of ripping mine off, because I've never had my chain go off that way.
    So you haven't had a bent derailer hanger yet?

    (That is what got my chain into the spokes)

    "it IS possible that you are faster or slower than anybody else who is having at least as much if not more or less fun"

  20. #20
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    Not yet, but I suppose anything is possible.

    I just replaced my old bike (maybe 2 months ago), so maybe I'll wait until the disk starts to look old before I remove it. I don't remember my last bike having one, so it must have broken off or I took it off after it became damaged. I rode that bike for 19 years - so I don't actually remember what happened to it.

  21. #21
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    Why is it the higher-end bikes tend not to have the pie-plate thingy?

  22. #22
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    @DennisF - (tongue-in-cheek) now I'll have to go see if my new bike has one so I'll know if it's a higher-end bike!! I don't know if does or does not have one, I assumed all bikes have them.

  23. #23
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    Quote Originally Posted by 2 Slow View Post
    I went for a ride today and noticed that the plastic cover behind the cassette was dislodged from it's normal position and when I got home I realized one of two plastic nipples holding it in place had broken off, therefore rendering the cover useless.

    I removed it from the bike so that it doesn't get in the way of my spokes, but would like to know if it's an important piece and whether to replace it or not.
    I would not bother to replace it....

    It prevents the chain from damaging the spokes if it falls off the cassette into the wheel side.

    You should pay a bit more attention and stop pedalling quickly if you think the chain may have fallen off that side, otherwise if you keep pedalling you could grind up some spokes as well.

    And yes no matter how you tune up your bike the chain can fall off to the inside.....think bent hanger trees, rocks, sticks twigs...etc.

    Mavic SLR's have a spoke protector (high-end wheel), but Shimano STR wheels (high end too) don't have aspoke protector...

  24. #24
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    Quote Originally Posted by DennisF View Post
    Why is it the higher-end bikes tend not to have the pie-plate thingy?
    Most high end builds are going for minimum weight.....and expert rider who will not grind a spoke or too if the chain slips into the spokes...

    on the other hand my Mavic SLR wheels did have a spoke protector (very small and light)....I did eventually drop and chain and grind off that spoke protector though.

  25. #25
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    ha mine just broke and started rattling around. time to get the snips out

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