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Help me fix my bike

  1. Jul 10, 2005 #1
    I've had this bike for about 2 years now. There is this really annoying clicking sound coming from somewhere in my front derailer. It happens in regular intervals relative to the turns in my pedals. (1 click for every time the pedal goes around) The sound is only there when I put a lot of torque into it when accelerating or climbing a hill. If I am just cruising, there is no clicking. I have a feeling it is coming from inside the axle that the pedals attach to but I can't be sure, that is just where the sound is coming from.

    Any ideas???

    thanks
     
  2. jcsd
  3. Jul 10, 2005 #2

    wolram

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    Souns like a bad bearing to me, some times one of the balls can get damaged.
    and only, "click", under load.
     
  4. Jul 10, 2005 #3

    brewnog

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    Seconded.

    It's amost certainly one of your bottom bracket bearings which is worn out. The good bit is you get to use one of my favourite and cleverest tools, - a crank puller.

    Depending on your bike, you need to either overhaul your bearings, or replace the BB as a unit. Let us know and we'll instruct you if you need it. Plenty of bike geeks around here.
     
  5. Jul 10, 2005 #4

    Chi Meson

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    Another possibility are the bolts that hold the chain rings to the front crank. There are five of these bolts, one side requires a 4 mm allen (hex) wrench, the other side requires either a special tool, but you can usually tighten this bolt without this tool. If you have a flathead screwdriver that has a really broad head, it can substitute.

    Try tightening each of the five bolts just a little bit. It is very easy to over-torque these guys (I've broken a few) so don't go overboard.

    Another possibility is your bottom-bracket might be loose. Assuming your bike is newer than 10 years old, this definately requires a special tool to tighten.

    What kind of bike is it anyway? How old, and where did you get it? You might be able to take it back to the shop where you got it to get it fixed, perhaps gratuit.
     
  6. Jul 10, 2005 #5

    brewnog

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    A good suggestion too. Remember, when tightening any bolts on a pitch circle, to tighten opposite 'corners', rather than going round in a circle (ie for 5 bolts, tighten 1, then 3, then 5, then 2, then 4, if you catch my drift).
     
  7. Jul 10, 2005 #6
    What you say makes me laugh a lot. :smile: :smile: :smile:
    You look fun, i am sure, when you ride your bike up hill; :smile: :biggrin:
     
  8. Jul 10, 2005 #7
    hmm. I'll go try your suggestion chi. I don't know much about about bikes so "depending on your bike" doesn't mean too much to me. Also, what is a crank puller?
    Not to sure what your getting at severfeelor; but if it makes you laugh...
     
  9. Jul 10, 2005 #8
    Crank Pull??!!! I prefer the hammer and pic method :smile: Actually, now that I think about it, I never needed a crank pull: When I changed frames my old frame's bb area was loose and the bearings slid right out.
     
  10. Jul 10, 2005 #9

    Moonbear

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    I don't know what a crank puller is either, but it has a fun sounding name and seems like a tool we really could use over in TD! :rofl:
     
  11. Jul 10, 2005 #10
    Is there any associated "jump" with the click? Does the pedal jerk forward at all when it clicks? If so, it could be a loose pedal or a worn chain or chainring.
     
  12. Jul 10, 2005 #11
    No, i actually don't understand, just the way you say really makes me laugh.
     
  13. Jul 10, 2005 #12
    ok. That didn't work. I couldn't tighten those bolts anymore than they were except for one, and that only moved a milimetre or two.

    Also, I have a new problem now...
    I was trying to raise my handle bars but there seems to be no screw to undo that actually loosens the post. there are two allen screws holding the handle bar to the post. so I loosened that and raised it a bit, but then I realized, but there are these stupid metal rings that are spacers between the bottom of the handle bar and the top of the frame tube for the post. So I couln't move the post up and I coudn't even raise the handles up a bit because then there would be space between the spacer rings and they would rattle all over the place. So I put everthing back together but something is loose. I think it is where the frame meets the fork. there is something loose and I can't figure out what it is. Ever time I go over even grooves in a sidewalk, it makes a clack/clunk/rattle noise and it sounds like soemthing is loose. I took the handles off 2 more times, and really pushed no them to make sure there was no looseness, but the noise is still there. I really need to fix this, cause it's even more annoying than the other clicking problem. It doesn't feel safe when I hear that noise cause I feel like the fork could just fall off any moment. (although I am confident it won't)

    thanks again

    oh ya, could someone go though the procedure/provide a link for fixing the problem in the OP cause I really don't know where to begin.

    thank
     
  14. Jul 10, 2005 #13

    brewnog

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    You have an AHead set, rather than a traditional style one with a threaded steerer tube. The chances are, that if all the spacers are already below your stem, you won't be able to raise your handebars. Are you sure you put it back together properly? I'm guessing not! Did you drop any bearings on the floor?! :smile:


    Since you've got an AHead type headset, I'm going to assume you've got a cartridge type bottom bracket too (relatively new bike).

    To replace the bottom bracket bearings:

    - Remove the cranks: Remove the bolt protector caps from the cranks, and remove the allen bolts/nuts holding the cranks onto the shaft. Bear in mind the possibility of one side having a left-hand thread.

    - Using a crank puller (or a hammer and a block of wood, CAREFULLY!) remove the cranks.

    - Using a bottom-bracket removal tool (or a hardened screwdriver and hammer, CAREFULLY!) remove the lockrings which retain the bottom bracket in the bb shell of the frame. The choice of BB-removal tool will depend on the BB in place, try a Shimano one first (most common). Depending on the bike, there might be lockrings on the left, right, or both sides. These get stiff, you might need some "persuasion" (bashing with mallet) to free the rings.

    - Unscrew and withdraw the bottom bracket cartridge from the frame shell.

    - Give the insides of the shell a really good clean, with some rags and WD-40 or equivalent.

    - Lube up! (The threads on the frame, not you).

    - Depending on how you took the knackered one out, stick a lockring back in, followed by the new (lubed) BB, followed by the other lockring.

    - Screw up nice and tightly

    - Replace cranks, nuts/allen bolts, and caps.

    Hey presto!
     
  15. Jul 10, 2005 #14

    Chi Meson

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    It's Probably the bottom bracket. A slight "annoying click" might mean the BB casing is loose; a more annoying, slightly crunchy, click would mean a bad bearing, but most BBs are "sealed bearings" these days

    uh oh. I agree with Brewnog. Before you start in on fixing your bike further, I am of the opinion that you should never do things without the right tools. You could go and buy all the right tools (for this job) and get a decent "How to" book probably for the same price that a bike shop would charge to fix this problem.
     
  16. Jul 10, 2005 #15

    Danger

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    Or at least in the Clinic.
     
  17. Jul 11, 2005 #16

    DocToxyn

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    First off, brewnog has provided a nice primer on how to break out the BB, but if you are replacing that item you must be sure to get the correct type for the bike you have. You either have to measure this or simply bring it into you local bike shop (LBS) and say "Can I have a new one of these?". The lube you use is also important, threads and bearings (unless sealed) should get some type of synthetic grease, chains and pivots get oils, waxes, etc. If you could provide us with the make, model and year of your bike, we may also be able to help in that respect. As Chi Meson states, if you are really going to get into this "biking thing", you would be better off learning how to fix/tune the machine yourself, it will save you time off the bike (while it in the shop) and money out of your pocket. You can pick up a basic tool set at online stores like nashbar for less than $50 and it will allow you to pretty much completely strip a bike and put it back together. I've got that tool set and while it's not top-of-the-line, it does what I need it to. Many bike parts, like the AHead set an only be serviced with specific tools and trying to get by with subtitutes will only cause damage, pain and frustration.
     
  18. Jul 11, 2005 #17

    DocToxyn

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    Here are some other useful, bike-related tools (I'm not making these up):

    third hand tool
    fourth hand tool
    chain whip
    cone wrench
    threadless nut setter
    nipple driver
     
  19. Jul 13, 2005 #18
    ok, I don't know the actual specs of the bike. It's a Jamis frame, manitou spyder shocks/fork and shimano stx rc gears.
    I still haven't solved the front fork/frame loosness problem. So I took it all apart, and in the bottom of the frames tube where the fork/handlebar post goes, there is a plastic ring and a ring of bearings. In the top, there is a metal ring and there is a plastic wedge that fits into this ring, there is also a ring of bearings here. I am having two problems putting this back together properly, at the bottom of the tube with the plasic ring and the bearings, is the plastic ring supposed to just sit there, or is it supposed to be pryed over the little edge/lip right at the base of the post. It looks like it should be pryed over the edge because when I put it back together, the metal edge is exposed and it looks like it doesn't belong. The second problem is that the wedge at the top doesn't seem to fit in very well, when the ring isn't over the post the plastic wedge fits fine but once on the post the plastic doesn't fit over the post AND into the ring at the same time. Is there some trick to get this in place or do I just have to really force it.
    These two things are the only things I can see that could be the problem, unless I have something in backwards or something, but I doubt it. Once I get this problem solved I can go back to fixing the clicking in the gears.

    thanks for all the help
     
  20. Jul 15, 2005 #19

    DocToxyn

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    Unless you built or had a shop build a custom bike for you, you have an entire bike produced by Jamis. I used to have one myself, its a great name in MTBs, just not all that well known. Check out the Jamis website and see if you can find your bike, it will help. As far as the problem, it's sortof hard for me to picture all the different pieces you are talking about since for one (and its not your fault) your terminology could be off. Bearings ride in cups and races, forks have steering tubes and on and on... I think it might help if you could find a name associated with the headset, it should be on there somewhere and then we could find a schematic. Once we get that, it should be a fairly simple re-assembly (hopefully). Otherwise, it shouldn't be too expensive for your local bike shop to fix this, maybe <$50?.
     
  21. Jul 18, 2005 #20
    hmm. ok, here is the newer version of my bike, but they only seem to have 04/05 model specs. I am not sure what mine is but it wouldn't be any newer than 02 maybe even 01 or 00. my fork is manitou but they are spyder not axel. and I don't have diskbrakes, and my gears are shimano, my brakes are avid though, so that is probably the same. I don't any problem with my brakes though :tongue2:
     
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