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  1. #1
    Member Bdude's Avatar
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    Changing gears by accident when bike is still

    Why is it bad to change gears while the big isn't moving? When I carried my bike to my apartment, before the elevator got fixed, I had to carry it several flights of stairs. At times, I would accidentally bump into something and when I rode it, the bike gears were messed up leading me to have to take it to the shop to be repaired. If only there was some way to lock the gears while you were carrying it so you wouldn't have to take it to the shop again. But yeah, why is it bad to change the gears without having the bike in motion? Could that cause permanent damage when done frequently?

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    When you shift the shifter while the bike is still (actually while the crank isn't turning; it doesn't matter if the bike is rolling or not), you force the derailleur against the chain as though it were going to shift. Since it has to be moving to guide onto the next chainring or cassette cog, though, the shift doesn't occur. In theory that can stress the derailleur, especially the rear, though I doubt it actually causes damage in real life. But the chain won't be squarely on the gear, so if you jump on the bike and start pedaling hard, it can jump toward the next gear and either spill you or tweak something. It's probably not as common as it used to be in the friction-shift days, and it's not a huge worry. From years of habit, though, I pick up the rear wheel and give the crank a spin before I get on the bike. If the chain is misaligned, that allows it to hop onto a gear.

  3. #3
    Bicycle Repair Man !!! Sixty Fiver's Avatar
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    Yep... before you ride give the crank a spin to make sure it is in gear and not somewhere in between.

    Takes 2 seconds.

    Saves grief.

  4. #4
    Member Bdude's Avatar
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    Quote Originally Posted by Velo Dog View Post
    When you shift the shifter while the bike is still (actually while the crank isn't turning; it doesn't matter if the bike is rolling or not), you force the derailleur against the chain as though it were going to shift. Since it has to be moving to guide onto the next chainring or cassette cog, though, the shift doesn't occur. In theory that can stress the derailleur, especially the rear, though I doubt it actually causes damage in real life. But the chain won't be squarely on the gear, so if you jump on the bike and start pedaling hard, it can jump toward the next gear and either spill you or tweak something. It's probably not as common as it used to be in the friction-shift days, and it's not a huge worry. From years of habit, though, I pick up the rear wheel and give the crank a spin before I get on the bike. If the chain is misaligned, that allows it to hop onto a gear.
    Sweet! Thanks a lot, dude!

  5. #5
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    If this is a big problem a visual check before you ride wouldn't hurt. Sometimes when stopped at a light on a group ride some friend will ride up next to you and tap the bifter two or three times just to be a joker. New riders panic and jump off the bike before the light changes and have to turn the crank to get into what ever gear the joker shifted them into. More seasoned riders simply look back at the cassette and see how many clicks it takes to get back in line.

    Don't ask me how many times I jumped off the bike.

  6. #6
    Fax Transport Specialist black_box's Avatar
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    would it matter if the derailleur spring was pushing against the chain vs. the next limit stop? I wouldnt think so. Just avoid spinning the cranks backwards and when possible, spin them forward to let the chain catch up to the shifter.

  7. #7
    Bike addict, dreamer AdamDZ's Avatar
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    You won't damage the derailleur, it's designed to take a lot more tension than that. The worst that will happen, if you push hard, the chain will not engage any sprocket and will slip (jumping over the sprocket teeth) causing the pedals to spin nearly freely and your feet might slip off the pedals causing you to fall or hit the crank or outright fall if you're clipped in. If this happens often you may risk damage to the sprocket teeth.

    Either do what Sixty Fiver suggested or start gently and allow the shift to complete before pushing hard. If you're facing uphill you have to do what Sixty Fiver said.

    Or, if you know how many clicks you shifted, just shift back to undo.

    Shift happens.

  8. #8
    Banned. Mr. Beanz's Avatar
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    Why not pop it in the small chainring before you start lugging? Chance are if you bump the derailleur, it might spin the pedal too into a nice clean shift! I do this with my stuff.

  9. #9
    Bike addict, dreamer AdamDZ's Avatar
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    Quote Originally Posted by Mr. Beanz View Post
    Why not pop it in the small chainring before you start lugging? Chance are if you bump the derailleur, it might spin the pedal too into a nice clean shift! I do this with my stuff.
    This happens to me very, very rarely and I usually just start slowly to let it complete the shift the shift back once I'm moving or I click back to undo. I don't like to shift chainrings unless I really need to, shifting chainrings takes too long IMHO. Also, I usually ride with panniers so lifting the rear wheel isn't a viable option either for me, but that may work well for light bikes. There are few options to deal with this so one needs to chose what shifts... umm suits them best

  10. #10
    Banned. Mr. Beanz's Avatar
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    Quote Originally Posted by AdamDZ View Post
    This happens to me very, very rarely and I usually just start slowly to let it complete the shift the shift back once I'm moving or I click back to undo. I don't like to shift chainrings unless I really need to, shifting chainrings takes too long IMHO. Also, I usually ride with panniers so lifting the rear wheel isn't a viable option either for me, but that may work well for light bikes. There are few options to deal with this so one needs to chose what shifts... umm suits them best
    True! I don' use my bikes for commute, strictly sport fun fitness. So if I'm heading to a mtn road where we'll be climbing 5,000 ft, I have no problem shifting my bike into the smalll gear beforehand!

    As far as our tandem, barend shifters so they rarely get bumped in transport.

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