Hello, Everyone.

I was putting my caliper back on to my Rebas (post mount) yesterday and somehow managed to strip the thread in the bolt receiver. It must be very soft metal as I certainly didn’t overtighten. Now I cannot attach the brake and ride the bike, so what do I do? It’s Sunday tomorrow and I want to get out and muddy! Help!

Thanks for any suggestions,

Dom.

Helicoil or similar. Relativly easy to fit. Dunno if you will get one on a saturday. Thats the real fix. However have a look at the length of the bolt – there might be some thread left in the bottom of the hole that a longer bolt could grip

Cool. I had heard about helicoil but will try a longer bolt in the meantime. The bolts are for Avid Juicy 3’s, so does anyone know the thread size? (Non engineer…bit woolly on things like that!)

ATB, Dom.

Thread should be M6x1 – nuthin fancy. I’ve asked my local motorcycle dealer/service shop about doing this recently, they gave me an estimate of £10-£15. It’s a cheap an “proper” fix. Bring back ISO – much more fool proof! 😕

I reckon I’ll be off to my LBS later…

Don’t get anything too long – you don’t want the bolt coming out the other end of the mount.

i’d take it to your friendly LBS. They will look at it and tell you if you can save it as TJ says with a helicoil, or not. It may be possible to just run a tap through it, but depends on how bad a state its in..

i think post mount forks should come with pre helicoiled disc mounts, the magnesium lowers are just too soft for decent threads.

i think post mount forks should come with pre helicoiled disc mounts, the magnesium lowers are just too soft for decent threads.

inserts like that can go wrong too, especially after multiple usues

helicoils are much stronger than the original thread. Some race motorcycle engine builders put helicoils in all threads as a matter of course to avoid issues with repeated rebuilds. I have never had a helicoil that was properly installed fail and I have used a few on cycles and motorcycles

glad to here it TJ, I work with inserts/helicoils everyday and have seen many issues.

Your engine builders use them so that the item you’re trying to protect isn’t damaged, that doesn’t mean the insert itself cant have problems. Funnily enough, this is the same reason we use them in the defence industry.

Fairy snuff.

I got them done by a local precision engineering shop on a previous bike – cost £10 cash for the pair

Just got back from the local motorbike shop, as recommended by Reluctant (see above). The guy there was very helpful and had a go at putting a helicoil in, but it wouldn’t hold. He ended up tapping a thread in a bit deeper so there should be some purchase for a longer bolt. Just waiting for a 185mm adapter from CRC, then I’ll have a go. Don’t want to put anything in before that as I,m not sure how many attempts I’ll get. Magnesium lowers sound great, but the metal is VERY soft.

ATB, Dom.

If you are concerned about the thread you could use a stud rather than a bolt and glue / loctite it in – then use a nut on it so the bit yo undo is nut on a steel stud not a bolt into the alloy leg

Not a bad plan B, TandemJeremy! Thanks for the idea.

TJ’s idea is sound, you could use something like Araldite to seal the stud into the leg, then use a bolt on the top!

My favourite stuff for a job like this is chemical metal!

I used some once to put a speedo drive back into a gearbox, the drive is still there 8 years later!