macpherson88 Posted August 23, 2011 Report Share Posted August 23, 2011 just wondering if anyone can help? I have sheered off a bolt in a v brake/magura adapter(4bolt to 2bolt). i could easily drill the sheered bolt out but how hard is helicoiling or is there another way? also stripped some magura threads but have tapped them up a size. havent rode trials for ages and trying to get bike going again as cheap as poss. all help greatly accepted. Quote Link to comment Share on other sites More sharing options...
wolf_rt Posted August 24, 2011 Report Share Posted August 24, 2011 Hi mate.. Helicoiling is for repairing damaged thread, not the best option for removing a snapped bolt. 1st thing, how/why did the bolt snap? if it snapped because of over tightening/faulty bolt, then as long as the thread isn't to badly stretched, the snapped off part should come out fairly easily. If it is corroded in there and snapped trying to loosen it, then it will go hard. So take the wheel off to give good access, I presume you have the adapter plate off, and the bolt is snapped flush with the frame? I have seen people get these out by hacksawing a few mm into the mount, through the bolt, and unscrew with a flat screwdriver. if you decide to drill the bolt, go to the hardware store and get the smallest "Easy-Out" or similar, and the appropriate size drill bit, and attempt to get it out this way. If you have to drill the bolt out entirely and helicoil it, it is very hard to keep the drill centered on the hard bolt and not dig into the soft alloy casting. basically you drill the whole out to the size of the bolt exactly, tap a new larger thread, then fit a helicoil to reduce the thread size.. not really helpfull unless you can get the bolt out... If it goes badly, it would probably be easiest to weld up the whole, then drill and tap a new thread in the correct position. the hacksaw trick would be my choice, but i'm dodgy..lol Quote Link to comment Share on other sites More sharing options...
macpherson88 Posted August 24, 2011 Author Report Share Posted August 24, 2011 the bolt sheered off flush in the actual mount where the v brake sits. i was only refitting my v brake then it snapped. was going to try cut a few mill off then mole grip the bolt out. think ill be getting a new hacksaw tommorrow..... Quote Link to comment Share on other sites More sharing options...
Tomy P Posted August 24, 2011 Report Share Posted August 24, 2011 Putting a helicoil in is pretty straight forward. Use a drill (pillar) preferably to drill it out. Use a tap for the thread and then screw the helicoil in et. voila. + much stronger than the alu thread Quote Link to comment Share on other sites More sharing options...
Silferme Posted August 24, 2011 Report Share Posted August 24, 2011 Or you might also consider welding a spacer to the end of the broken bolt and use pliers to twist it out? And if you decide to drill it out, you should try to get hold of a reverse drill bit for it. The broken off bolt might even come out while you are drilling with that. Quote Link to comment Share on other sites More sharing options...
Adesaxo31 Posted August 28, 2011 Report Share Posted August 28, 2011 You want an easy out most car part dealers sell them Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.