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Stripped thread on Fox forks

GiantTranceRider's picture

By GiantTranceRider - Posted on 12 May 2014

NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.

Hi all, ive stripped one of the threads on the brake post mount on my fox forks im just wondering if anyone out there has had any experience with helicoils to fix a stripped thread on forks & how hard it is to do.
Thanks for any replies.

[Mod. moved to MTB gear]

fairy1's picture

I don't think there would be any fork that would have enough meat to fit a Helicoil.

First I'd check the depth of the hole with a piece of wire and see if you can get away with a longer bolt. If not you would have to use something like an metal loaded epoxy and drill and tap in to that.

Cotic Tony's picture

I've successfully helicoiled two forks now with absolutely no problems at all.
I was extremely careful making sure that the tap was dead straight, that the drill didn't wobble causing an enlarged hole & that I didn't go any deeper than necessary.

At the end of the day if it fails you'll either strike oil or it will give when tightening up. Either way you've not much to lose. Once tight with approx 10mm of thread held it won't rip out. Some say that a helicoiled thread is stronger than the original.

Funkychicken's picture

Helicoils will work, and are arguably tougher than the original thread. How far the thread is stripped isn't usually an issue since it will be possible to fit 1 and a half helicoils in the post mount without drilling into the body. Mine fit in with about an extra 4.5mm away from the edge of the post mount, and I used a longer bolt to reach in for engagement with the thread. You'll need your bolt to engage at least 9-10mm into solid thread for a good grip.

I wouldn't DIY though unless you've got precise tools to do the job. Get your LBS to do it - it's a standard job for them and $50 incl helicoils is worth the price imo.

fairy1's picture

Haha, seems I was wrong then.

How would a bike shop do it to get it perfect? I'd imagine my LBS would send it out as it would be in their too hard basket for sure.

Tom M's picture

With helicoils the trick is to go 1.5 to 2 turns deeper then the outside of the hole (flush).

Normally very easy to drill because the drill is the size of the original thread that's already stripped so your just shaving it really and it's alloy. So a stripped m6 thread would be a 6mm drill.

Discodan's picture

If you get a kit it should have the right sized drill bit included, it's not too hard at all

GiantTranceRider's picture

Thanks for the replys & info! So i decided to do the helicolis myself & turned out to be a pretty simple process & the thread are better than new! Happy days!

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