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Removing stripped bolts

I recently broke the head off of the steerer tube bolt on my road bike, when I was reassembling it when I landed in Spain. Had to wait for someone - who was less than friendly or speedy - to remove it and replace it. Not happy.

Now the #3 hex/allen bolt on my bottle cage on my tri bike is stripped.

I need a tool that I can take with me on the road that can remove stripped bolts and broken bolts. I see Craftsman has some options online, but don't know how well they work. Besides, I don't like to buy stuff sight unseen and personally untested. I want one that doesn't require electricity (ex, a drill bit) to work.

Any ideas?

Comments


  • Posted By Scott Alexander on 28 May 2014 01:28 PM

    I recently broke the head off of the steerer tube bolt on my road bike, when I was reassembling it when I landed in Spain. Had to wait for someone - who was less than friendly or speedy - to remove it and replace it. Not happy.

    Now the #3 hex/allen bolt on my bottle cage on my tri bike is stripped.

    I need a tool that I can take with me on the road that can remove stripped bolts and broken bolts. I see Craftsman has some options online, but don't know how well they work. Besides, I don't like to buy stuff sight unseen and personally untested. I want one that doesn't require electricity (ex, a drill bit) to work.

    Any ideas?

    If you're removing, and stripping, a stripped bolt in the field, than you didn't do it right, which is to check all of your stuff at home where you have access to all of your tools, spare bolts, etc. 

    You want an impact driver, I think, but my point is that if you're in a hotel using a manual impact driver on a stripped or broken bolt on your $6k carbon bike...you've already boogered several steps that would have prevented you from whacking your bike with a hammer. Just sayin 

  • I have a MAC tools multi bit kit with a baby ratchet and extension. It has torx, hex, phillips, slotted, metric and standard. I take it with me on every trip I have my bike. Last time the hex on my seat got a little sloppy and the 5mm hex driver wouldn't grab I used the closest torx that fit and it was grabby enough to break it loose. Broken bolts are something else altogether, probably pack a good quality needle nose vice grip and hope for the best. Be aware of broken bolt extractors, I work as a auto repair tech and haven't found one worth a shit yet. I have found that most bolts on bikes have about a 3 cycle life span. If you take them off a couple of times you should replace them.

  • Broken bolts stink. I'm a mechanical engineer by education (work as a petrophysicist now), and I am a car hobbiest as well. Dad was a lifetime car guy, and racing guru. I spent a lot of my youth helping with race cars. I still tinker with cars.

    Scott, I'm going to be mean and start with the heavy dose medicine first. Stop overtightening the bolts! That causes them to stretch beyond their designed tension and preexisting flaws then become breaks! I'm not going to go on about fracture mechanics, but you are overtorquing the bolts! Get a torque wrench if you are one of those I have to check every bolt every week kind of guys. I use a torque wrench and then just never worry about them ever after. If you are really worried get some blue loc tite (not red) and use a torque wrench. Then it won't move until you take it apart and it's at the proper torque, which yields the proper "clamping force" which is what we are really after.

    3T does a great job labeling all of their parts with the correct torque. You can use their values for a 4mm hex drive on anyone's parts that are the same size. The torque and hence clamping force will be similar.

    Now that the heavy medicine has been taken (sorry man), if you have a broken bolt, you can try needle nose pliers, other tools if they are stripped, but if its broken you are going to need a good drill and broken screw extractors. And honestly these are last resort tools. They likely lead to real problems like having to use heli-coils or other repair methods, none of which we want on carbon frame bikes.

    Now if you have a bolt removed, compare it to others of the same size. If you see odd uneven or damaged threads, throw it out. If you see stretching of the bolt necks down to smaller diameter anywhere on its length throw it out. Any of these can lead to broken bolts later.

    As long as a bolt never exceeds it's design torque, it should be reusable for a very long time (100s of times), but in practice pre-existing flaws (small cracks and nicks) prevent this from being realized. Metals a crystalline structures and crystals will break at a flaw.

    Use a torque wrench, inspect the bolts, and remember "just a little bit more" when tightening a bolt in fact will be worse over the long run.

    And since you are in Dallas, if you ever need help, I have a lot of tools at my disposal. I do a lot of my own bike wrenching too.
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