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enter image description hereI recently got into a small bike accident and the handlebars became loose. It seems to not be in sync with the front bike tire. I tried to tighten the headset and locknut, nothing seems to work. I can easily turn the handlebar into a new position with the tight bolts, which is the issue. Is there any other possible ways to fix this?

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    There are several different schemes for mounting handlebars, and two major schemes for how the handlebar stem attaches to the front fork. We need to know a little more about your bike and problem to be of much help. (Is the handlebar actually loose, or does it simply not line up with the tire?) – Daniel R Hicks Jul 2 '15 at 1:17
  • A picture of your front set up would definitely help helping you. – super Jul 2 '15 at 4:06
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    That's a threaded headset. Easy fix, see my second paragraph below. That rust colored spot is the top of the bolt you need to loosen. If you adjusted the headset locknuts you'll probably want a shop to check the adjustment on them. Adjusting threaded headsets is one of those skills you need to develop a feel for. It doesn't take long to do, just requires a certain feel. – ChrisL Jul 2 '15 at 5:12
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When you say out of sync I assume this means that when you look down while on the bike the handlebars point one direction and the wheel points in a slight different direction.

You say locknut so that implies a threaded headset. If so, simply loosen the bolt on the top of the stem and realign the stem with the front wheel while straddling the bike. Note this will also now allow the stem to lower down into the frame so be sure to first mark the height with a piece of tape. Threaded headsets are no longer the norm except on low end bikes and older bikes. Adjusting the lock nut and headset requires a pair of large open-ended wrenches.

If the stem has bolt on top (when you look down on it while riding) AND at the back of it. Then you have a threadless headset. These have been the norm on most bikes for the past ~25 years. The "locknut" you're referring to is the bolt on top of the stem (this bolt holds the fork/frame/stem/headset bearings together and keeps them properly compressed)***. If this is the case then all you need to do is loosen the bolt (or bolts - could be 2) which will allow you to swing the stem and bars left/right. Line the stem with with the front wheel while straddling the bike and then tighten the bolts. Take care not to over tighten the stem bolts! Don't go gorilla with the wrench (this rule applies to almost anything on a bike!) Given the safety repercussions of improperly adjusted stems it would be prudent to have a trained bike mechanic double check your work.

***If you did monkey with the top bolt you may have messed up the adjustment of your headset bearings. Don't panic, it's an easy fix:

  1. Loosen that top bolt however many turns you think you tightened it and maybe a few extra. Also loosen the bolt (or two) at the back of the stem.
  2. Set the bike on the ground, stand next to it and turn the handlebars 90 degrees. Now squeeze and hold the front brake. Don't let go.
  3. Try to roll the bike back and forth. You should feel a slight knocking sensation. This is play in the bearings (bad!)
  4. Tighten the top bolt a half turn. Repeat steps 2 & 3.
  5. Repeat step 4 until the knocking sensation is gone. Key here is to adjust the top bolt in very small increments until the play/knocking is just removed. Any tighter and you'll create binding which will prematurely wear out the bearings.
  6. Tighten the bolt or bolts at the rear of the stem.
  • I did loosen the bolt and put it back into place, though once I tightened the bolt. It would still be moving the handle bar as if the bolt was loose. Can't find the issue. – Steven Tran Jul 2 '15 at 12:41
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    Did you loosen the bolt or remove the bolt? When you try to tighten the bolt does it get tight or does it keep spinning? If it keeps spinning instead of getting tight then the wedge at the bottom of the stem came undone. Remove the stem completely, turn the bike upside down and the wedge should fall out (might need to give it a poke with a long rod/stick/etc. Reattach the wedge, put the stem back in the frame and tighten. – ChrisL Jul 2 '15 at 15:56
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    I loosened the bolt, and it does get tight. It seems be another issue besides the bolt and locknut. – Steven Tran Jul 3 '15 at 18:01

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