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Broken Cylinder Head Cover Bolt

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I was replacing the cylinder head cover today and trusted my torque wrench too much. The bolt on the kickstand side snapped off. Any suggestions on the best way to extract the broken bolt? Thanks.

What is left of the bolt...

1086632584_brokenbolt.thumb.jpg.fcda62377506dc8a0ad8d8be7457e16b.jpg

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As its not cross threaded and just failed due to too much stretch, likely now that its broken and tension released, you can rotate it out with a very small center punch and small taps from a hammer. There is no need to go caveman on it. you may even find you can rotate it out with just a pick


Center punching , drilling small pilot hole, and then using a larger left hand drill bit will also work.


If you have to resort to a screw remover (easy out) something went very wrong in the easier steps and ways

 

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You are going to make me go into my rant on torque wrenches. It is a 7mm threaded shoulder bolt.  Essentially no stretch to it.  Trust your feel. Tighten medium snug and call it good.  At least you did not break one of the cam journal caps by over tightening.

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6 hours ago, Noble said:

You are going to make me go into my rant on torque wrenches. It is a 7mm threaded shoulder bolt.  Essentially no stretch to it.  Trust your feel. Tighten medium snug and call it good.  At least you did not break one of the cam journal caps by over tightening.

I could not agree more. Trust yourself on how much torque to apply to a bolt based on size and type of metal and it will likely be appropriate for most cases.

Edited by Augoose

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If your able to sharpen your own drillbits you can take one around 3/16" and sharpen it backward to grab the stud . It won't look right but as long as it's got the correct reliefs it'll dig in a grab , even drill material out if it's sharpened good enough, but your really only after it grabbing and turning the stud out .

 

 

.

Edited by jjktmrider

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Put a dab of grease on it to catch any shaving from a reverse drill bit and easy out.  As mentioned above, it could be very easy to extract without any tension on it.

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17 hours ago, Noble said:

You are going to make me go into my rant on torque wrenches. It is a 7mm threaded shoulder bolt.  Essentially no stretch to it.  Trust your feel. Tighten medium snug and call it good.  At least you did not break one of the cam journal caps by over tightening.

Definitely a right tool right job kind of deal, and better to go without if you do not have the correct tool.2021613021_TQwrenches.jpg.314ccd0f8ffd58087cdcc4aad27f317f.jpg

 

Thats one of two drawers  I have stuffed with TQ wrenches 9 in all and that only covers bikes, through medium trucks and such.
1/4" INLB to a 3/4" FTLB one I rarely use anymore 
Tested, certified, calibrated...

If your not using a Tested, certified, calibrated 1/4" drive tq wrench on 6 mm and smaller fasteners don't use one at all.

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Plus you need the correct torque spec which are not always right in any service manual.  And thread lubricant type or none further confuses the issue.

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18 hours ago, Noble said:

Plus you need the correct torque spec which are not always right in any service manual.  And thread lubricant type or none further confuses the issue.

Absolutely 
And when talking small fasteners,  even thread lube type and technique matters.

 

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Thank you to everyone who replied. I started with a left handed drill bit and was able to make a small dent in the bolt, but not turn it. I had some bits for removing stripped screws (gentler than an easy out) and I was able to back it out using one of them. The threads deformed a little at the top, but I was able to gently get the new bolt in and everything is put back together. Learned my lesson about blind trust and torque wrenches.

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