Stripped thread on post mount fork

tez001
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Stripped thread on post mount fork

Postby tez001 » Sun Dec 03, 2017 4:01 pm

Was adjusting my front disc calipers and have stripped the lower mount on the front fork - post mount.
I was in the process of getting them snug with a allen key before putting the torque wrench on it.

I doubt they'll give me warranty on the fork, so my options are:

- pay for a new fork (can I get any post mount fork?)
- heli coil? to fix the damaged thread

Helicoil will be the cheapest so that's the route Im thinking of.

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find_bruce
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Re: Stripped thread on post mount fork

Postby find_bruce » Thu Dec 07, 2017 7:55 am

Top or bottom bolt? If its a top bolt, the force is purely in compression so I would just use a helicoil.

I would want to think a bit more before using a helicoil on the bottom bolt, to see which direction the forces operate - properly installed a helicoil should be as strong as the original part, so I am probably just over-cautious.

tez001
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Re: Stripped thread on post mount fork

Postby tez001 » Tue Dec 12, 2017 3:11 pm

From all reports, a helicoil should be as strong, if not stronger than the original.
Warranty denied on it (as expected) so I've just run a helicoil through it, and don't need to worry about it stripping out in the future when I adjust the brakes

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Duck!
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Re: Stripped thread on post mount fork

Postby Duck! » Tue Dec 12, 2017 6:36 pm

If it's a big-brand fork you should be able to replace just the lower rather than the whole fork if the helicoil doesn't do the trick.
I had a thought, but it got run over as it crossed my mind.

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alrsv1
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Re: Stripped thread on post mount fork

Postby alrsv1 » Wed Dec 13, 2017 10:32 am

Could you tap the thread one size up then use an appropriately sized bolt? assuming it still fits through the caliper
mounting hole of course, and any spacers.
1997 Ritchey Road Logic, 1998 Frezoni MAX,
1992 Cannondale M2000, 201Pivot Mach5.5.

tez001
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Joined: Mon Nov 11, 2013 11:05 pm
Location: Sydney

Re: Stripped thread on post mount fork

Postby tez001 » Wed Dec 13, 2017 10:45 am

Sorted. Used a helicoil to tap in a new thread of the same size with the insert. I tried a die set on the original thread however that didn't work.

Rather than tap the next size up (and potentially have the same issue later on down the track) I opted for the heli coil.

@Duck, cant replace the lowers as this is for a road bike

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