how do you remove a stripped bolt (top cap)

Discuss light weight issues concerning road bikes & parts.
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by artray

David Blaine

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by mrfish

The ez out is possible. But much easier just to drill the bolt head, particularly if you used a lightweight aluminium bolt. Start with the largest drill which fits into the allen socket and drill down maybe 3-4mm until the bolt head drops off. Should be possible to do this without damaging even the top cap.

Another alternative is to grind down a slightly larger allen key with a slight taper, then hammer it into the bolt head and unscrew. You need a bench grinder and a steady hand to do this. It takes a long time to do properly, but enables you to unscrew and possibly re-use the bolt. I've used this technique for exotic aero bar bolts which cannot be replaced.

by Weenie

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by Kennyg

Did you get it off?

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by eric

stella-azzurra wrote:Eric, extractors are made to extract bolts. This is a puny top cap bolt which is low torque. We are not talking about a rusted bolt that is seized. Please.

The extractors break when you get them in the screw and accidentally put side force on them. The small diameter ones snap very easily.

But hey, if you think I'm full of it, go for it.

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by ghisallo2003

If it will not loosen by turning the stem, I would quite quickly just go for drilling it out. Find the guy or girl you know who is best at this kind of off-the-cuff work and get them to help. With the right set-up it is a 5 minute job, including a tea-break, and you can just insert a new bolt and be on your way.

Key is setting up with a good central drilling position, with the stem clamped firmly down, and preferably a mounted drill. Use a drill bit of the right size (smaller than the head of the stripped bolt) and then drill until you can thin the shoulder of the bolt. It will then come free with some encouragement. Good luck.

roca rule
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by roca rule

i already removed it. i wanted to the stem turning solution to work, but my stem has only a 2mm spacer and was not able to turn. my dad is a handyman and he lend me the extractor bolt. but what i ended up doing is getting a hex bit that barely fit in and lightly hamer it in and carefuly turn it until it loosened.

roca rule
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by roca rule

the next question is has anybody tried another cap expander on a look 595 (like tune gum and tune cap). if so how how does it work compared to the stock one.

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