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Adventure Mapper
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Discussion Starter · #1 ·
On the Thomson x4 stem I have, it has cracked in two places.
The steerer clamping bolts are seized (sweatified with salt) and I have stripped out the 4 mm allen heads on both. I tried a few methods, including dremelling in a slot for a scredriver....
I still have seized bolts, have wondered about a few other possible methods.
-Heat the bolt , slowly hoping to loosen the salt/corrosion.

-go to harbor freight tools and buy an east our set and try to drill in a small hole into the bolt head to get a very small ez out.

Thoughts?
 

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If you're not trying to save the stem, consider just dremelling the bolts in half at the stem's slot.

If you do want to save the stem, you might start by carefully drilling the head right off the bolt, which releases its grip on the steer tube. Then you can immobilize the stem properly and take a shot at drilling down the bolt from one end or the other. If you drill from the non-head end with right-hand-twist bits, then the bolt may even begin to turn with the bit and spin out of the stem.

Good luck!
 

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What cracked, the faceplate or actual stem? If the faceplate, then simply either drill out the bolts or cut them in the space between the faceplate and stem. If it's the actual stem, thenas mechBgon suggetsed either drill the heads or cut them. One little bit of advice for future reference, you need to remove and regrease stuff like that at least once a year, more if you sweat that toxic type sweat some people do or you'll be faced with this problem again.
 

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In the gap between the headset and the plate (hopefully you have one) cut the bolt close as you can to the plate leaving enough of the stud sticking out to get vise grips on the studs to remove them. If you don't have enough of a gap like me, then cut or drill the bolt heads off and remove the studs with a vise grip or stud remover. Cutting them off will probably ruin it though. You almost need a drillpress to do the job right without ruining it. A bridgeport mill would be perfect for the job. It all depends what you want to save. It might be easier to just cut it to get the bars free and buy a new stem. Watch your torque when installing things (for sure)!
 

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Adventure Mapper
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554 Posts
Discussion Starter · #6 ·
Thanks for the tips guys. No gap. What I ended up doing was using the easy out style bolt removal bits (reverse drill bit things). Used hand power, not a drill, I busted the bit off inside the stem bolt head. Then, trying to drill out the hardened steel was a chore and a half. I used metal specific drill bits, along with a dremel + cone shaped grinding stone to drill through the head. Used the same drill the bolt head off method for the other stem bolt and it went a lot faster. I never want to do that again.
 
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