Bicycle Mechanics - Stripped Cable Anchor Bolt

I recently stripped the cable anchor bolt on my Dura Ace rear derailleur (actually I think it was already stripped when I bought it on eBay!! lesson learned)

Anyhow, has anyone repaired this? I'm thinking of buying a helicoil kit. Is there enough material to hold the helicoil in place on the derailleur mech. Actually I think there was a helicoil in it already, is this standard on DA derailleurs or was it stripped before by the previous owner?

Does anyone know the thread on the bolt? is it 5 x 0.8

Thanks for your help

I did the same thing on an old SunTour derailleur. There wasn't enough material or even decent enough access to the hole. Since it was 25 years old, I just bought a new one.

Az

You could try tapping it out to the next larger size bolt.

I'm almost certain the thread is M5x.8 as you surmise. The next common size up is M6x1.0.

If just the bolt is stripped, get a new bolt. If the nut is stripped, get a new nut.

If just the bolt is stripped, get a new bolt. If the nut is stripped, get a new nut.

Since the OP discussed helicoils, I think it's safe to assume his issue is with stripped threads in the derailleur body, not just the bolt. It makes sense as most derailleur bodies are soft alloy, most bolts harder steel.

Since helicoils also require tapping to a larger size (though with a larger non-standard helicoil-specific tap), the easiest solution is to tap to the next largest metric size.

Since the OP discussed helicoils, I think it's safe to assume his issue is with stripped threads in the derailleur body, not just the bolt. It makes sense as most derailleur bodies are soft alloy, most bolts harder steel.

Since helicoils also require tapping to a larger size (though with a larger non-standard helicoil-specific tap), the easiest solution is to tap to the next largest metric size.

Yes this is correct sorry for the confustion here is a pic. You can see the helicoil pushed through the derailleur body. I might try the helicoil as I found this kit on Amazon pretty cheap (probably cost almost as much to buy a drill bit and tap!). Also, this way I can use the old anchor bolt and washer

http://www.amazon.com/Helicoil-5546-5-Thread-Repair-Kit/dp/B000BB8XLG/ref=sr_1_1?ie=UTF8&s=automotive&qid=1203479417&sr=8-1

Yes this is correct sorry for the confustion here is a pic. You can see the helicoil pushed through the derailleur body. I might try the helicoil as I found this kit on Amazon pretty cheap (probably cost almost as much to buy a drill bit and tap!). Also, this way I can use the old anchor bolt and washer

http://www.amazon.com/Helicoil-5546-5-Thread-Repair-Kit/dp/B000BB8XLG/ref=sr_1_1?ie=UTF8&s=automotive&qid=1203479417&sr=8-1

Wow, that looks like a really amateurish helicoil installation. If you can remove that insert and still have threads in the derailleur body, make sure the new insert is completely inside the aluminum, not sticking out either side, like in your picture. :eek: It'll work much better that way. :D

Wow, that looks like a really amateurish helicoil installation. If you can remove that insert and still have threads in the derailleur body, make sure the new insert is completely inside the aluminum, not sticking out either side, like in your picture. :eek: It'll work much better that way. :D

This is a picture of the 'stripped' derailleur. I guess its not so much stripped as the original helicoil has been pushed out!

Do DA derailleurs typically have helicoil inserts OR was this derailleur repaired with a helicoil from the previous user?

Yes, I intend to make sure the new insert is completely inside the aluminum, I may need to trim it with a dremel or something. Anyhow if I go this route I will try to document each step in pictures for furure userd reference.

Thanks for all your advice