Just got my forks back from TFTuned, dead excited, setting the bike back up. Last thing to do - reattach the caliper. First just screwed one bolt in and with no pressure at all it just turned in the boss. The other one tightened fine. I removed the offending allen blot and it brought all the tapped alu from the boss with it. Bugger. I kind of think it might have been the amount of old threadlock there was on the bolt. As an interim measure I just greased it up and gingerly screwed it back in ( a bit more than fingertight) so the bike is sort of useable. What now? I think my options are: - Retap myself, I doubt I can get a 7/8mm bolt through the caliper slot though.
- Fill with liquid metal and retap (is this possible)
- Tig the hole up and retap
- Press an insert in (a curveball, I haven't the insert or tools!)
- Take to a bikeshop and get loads of tutting and a big bill
- Take to a local framebuilder ( I think there's one in Croydon)
Any ideas?
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 Are there still small engineering workshops in the UK? If so take it along and ask them to helicoil it.
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 Is there space to tap the hole bigger and fit a helicoil? That should be the most reliable solution. If you know what metal teh fork lowers are made from welding might be possible, but usually the heat from welding will lead to local hardening near the brake boss, so there is a possibility of a reliability problem. The liquid metal might work too if it bonds well with the fork lowers...
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Fork lowers are usually magnesium so expect spectacular results if you try to weld it! Don't.
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 Are there still small engineering workshops in the UK? If so take it along and ask them to helicoil it. Yes there are, a very good friend of mine runs one. He regularly gets customers of my LBS out of trouble. I haven't seen a post mount fork that he couldn't helicoil yet. And it seems that there are a hell of a lot of ham fisted twits trying to work on their own bikes.
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 Why not get a longer bolt, then a nut as thin as you can get and use the nut to tighten it against the mount? it's a bodge but it's the most elegant solution I can think of.
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 There are loads of small engineering companies around here too. Anyhow, I got my old Marz forks heli-coiled with splendid results. And, although I can be a ham fisted git, I hardly applied any pressure when I fooked mine up, honest. I now have a torque wrench which hasn't been used yet, and I have to confess that last week I split my seat post collar on the road bike due to sheer ham fistedness (I'd forgotten that I had purchased the torqure wrench). 
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Proper Ham fisted attempt at tightening the hose cable join thing, snapped the metal join bit clean in half
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A torque wrench wouldn't have helped me, the threads came off like butter. I'm a mechanical engineer who's been building and wrecking bikes for years and I was gutted I did it! Helicoils look ideal (it's an IS post mount so the old threaded bar idea wouldn't work). I've looked in yellow pages etc. I'll start ringing round workshops on Thurs when I've got spare time, I'm not optimistic though as I approached a few last year to try to get some BB shells made. Anyone know a good little jobbing workshop that can heliciol my forks in the South East (I'm Epsom). Cheers for your ideas, at least I don't have to chuck them out (damn - no excuse to upgrade!)
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Have a look on Ebay for Helicoil kits too - it's not difficult to do it yourself once you're careful to drill the hole in line with the old one. Use cutting fluid or oil to make sure the drill and tap stay cool and run freely. Also make sure you don't drill too far and hit the pressure/oil holding parts of the fork...
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Brill, a £15 helicoil kit it is then, wish me luck!!! This forum is great, I hadn't even heard of Helicoils before last night. I'll post in a week "Help I need to drill out a Helicoil"!!!
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