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see me rollin, they hatin
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Discussion Starter · #1 ·
So i got a decent used bike, 2013. frame and fork were practically immaculate, so i know they're not old and beat to shyt.

front brakes were cheap and crappy, so i bought newer better ones. WELL. upon installing them, i find that the fork mount that holds the lower bolt of the brake, is stripped. This is in the meat of the lowers, not the bolt itself. I REFUSE TO BUY A NEW FORK!!!! There's got to be some way to remedy this. As it is, the brakes have a slight wiggle and the bolt will not hold tight, obviously. it just ate the aluminum threads right off, and i'm pretty sure it was not my fault. i didnt even work hard to get the bolt out and back in.

what can i do? the fork is not a beat turd, it's still pretty nice. i cant really responsibly afford a new one, and i just got this fuqing bike:mad:. I've heard of coring out new threads, but wont that make the hole wider incompatible with the brake bolt? HALLLP!!!
 

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well now i'm reading something about a helicoil. is that a good fix?
Yes, if done correctly a helicoil (aka recoil) gives a stronger thread than originally and is a permanent repair.
Brake post bolts are M6. Call around your local machine shops and see if they can help, the kits would normally cost you more than paying someone to install one from their kit.
 

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Cactus Cuddler
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If done by somebody right, helicoil works (basically it's threading it for a bigger size bolt, then putting the helicoil itself in there to make it smaller). Keensers are the same thing basically, iirc.
A machine shop that isn't inordinately busy (find one that isn't doing production) can do that really quickly and easily for cheap, and likely will have M8-M6 helicoils around, if nothing else than to keep their own fixtures working over use.
 

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Could you drill a hole right throgh it and put a nut on the other side with a longer bolt?
Drill a hole. Through the fork's lowers. Where all the oil and other important bits are. Which normally don't have big holes in them so all the aforementioned oils and don't end up on the outside of the fork. :skep:

Try that on your forks and let us know how that works out for you.

Like Dougal says, get the helicoils.
 

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Drill a hole. Through the fork's lowers. Where all the oil and other important bits are. Which normally don't have big holes in them so all the aforementioned oils and don't end up on the outside of the fork. :skep:

Try that on your forks and let us know how that works out for you.

Like Dougal says, get the helicoils.
Well the OP didn't specify which fork it is, but you could "drill a hole" with some forks without touching the the insides of the fork. Depends on the type of mount, right? Just asking if this was possible with OP's fork. By "drilling a hole" I meant removing the old thread so that the new bolt could go through, not trying to drill for oil..
 

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Well the OP didn't specify which fork it is, but you could "drill a hole" with some forks without touching the the insides of the fork. Depends on the type of mount, right? Just asking if this was possible with OP's fork. By "drilling a hole" I meant removing the old thread so that the new bolt could go through, not trying to drill for oil..
Show me any single post mount on any fork, cheap or not, that you could "drill a hole right through it and put a nut on the other side with a longer bolt", as you said in your previous post. I'm having difficulty seeing where you would affix said nut.
The only way this would work is if you had a fork with the old style IS mounts (which the caliper bolted from the side). If you did have one like that, then yes, you could do what you are suggesting, but on almost any fork made in the last 6-8 years that has post mounts, then it won't work. Given the OP's bike is from 2013, it is exceeding unlikely to have a fork with IS mounts.
 

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see me rollin, they hatin
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Discussion Starter · #11 ·
it's a manitou tower. the mount is a long metal finger-like projection that would not be drilled thru. i guess helicoil is my answer. tapping out a bigger hole means that the new larger bolt could not fit the brake.

i also got this bike at a shop, it was a shop demo, and lightly used, but i know this fork was nearly new because it's basically scratch free. i worry if i tell them there was a stripped bolt, they'd say it was my fault. i had no issue getting the bolt out, aside from the stickiness of the large amount of locktite in there. getting it back in wasnt hard either, so i know i wasnt pushing it's limits. i have a feeling somebody stripped the hole before, and tried to make up for it by splooging a bunch of locktite in there.
 

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It sounds like someone knew they missed up, so they added a ton of loctite. But I've seen many times where the hole gets stripped because someone put too short of a bolt in, so when it is properly torqued there's not enough threads holding on, so the threads get pulled out. Try a bolt slightly longer & I bet you'll be fine.
 

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Try a bolt slightly longer & I bet you'll be fine.
On a brake post - that's a very VERY bad idea! You need to have all the threads you can in contact with the mount bolt as there is a LOT of pressure on that front brake (70% of your braking force). Rear brake I'd consider chancing it but front brake? Nowayinhell! Do it RIGHT with a helicoil.

Have FUN!

G MAN
 

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see me rollin, they hatin
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Discussion Starter · #14 ·
the bolt seems long. it bottoms out with about 2mm to spare (extra bolt length) and spins freely. i have a friend offering to maybe drill out some adapters, etc, but i think the helicoil is the safest bet as to not permanently drill bigger holes that need odd sized bolts
 

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Show me any single post mount on any fork, cheap or not, that you could "drill a hole right through it and put a nut on the other side with a longer bolt", as you said in your previous post. I'm having difficulty seeing where you would affix said nut.
The only way this would work is if you had a fork with the old style IS mounts (which the caliper bolted from the side). If you did have one like that, then yes, you could do what you are suggesting, but on almost any fork made in the last 6-8 years that has post mounts, then it won't work. Given the OP's bike is from 2013, it is exceeding unlikely to have a fork with IS mounts.
Fair enough, my bad. It would have to be an older fork.

Sent from my GT-I9300 using Tapatalk
 

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aka dan51
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the bolt seems long. it bottoms out with about 2mm to spare (extra bolt length) and spins freely. i have a friend offering to maybe drill out some adapters, etc, but i think the helicoil is the safest bet as to not permanently drill bigger holes that need odd sized bolts
This might be why it stripped in the first place. Bolt bottomed out, you saw it wiggled and needed more tightening, proceeded to tighten which stripped the threads.
I've also seen that same process push the bolt through the lower and cause an oil leak, basically ruining the fork.
You got lucky with just stripped threads.
Get a shorter bolt or some washers before trying again after the heli-coil.
 

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see me rollin, they hatin
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Discussion Starter · #18 ·
oddly, there was no resistance though, not when putting it in. nothing felt cross threaded, and i certainly didnt force it when it was spinning. it just never ever felt tight the whole way thru. there was a lot of aluminum gunk spirals in the bolt threads when it came back out. i dont think the bolt started out too long in the first place. it was weird. but somebody also pointed out there might be shrapnel at the end of the hole thats not letting it back in all the way, including all that loctite junk.
 

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i worry if i tell them there was a stripped bolt, they'd say it was my fault. i had no issue getting the bolt out, aside from the stickiness of the large amount of locktite in there. getting it back in wasnt hard either, so i know i wasnt pushing it's limits. i have a feeling somebody stripped the hole before, and tried to make up for it by splooging a bunch of locktite in there.
I would let the shop know, if they are good they will try to help if not don't give them your business again
I would absolutely let the shop know. Trying to fill it with Loctite and hoping you don't find out can cause a serious issue on the trail at speed. Rip your caliper off on a downhill and wrap that hydraulic hose into your front spokes would not be pretty. Whether they fix it or not is on them, but, i'm sure it could be proven that whoever filled it with Loctite did it for a reason. If it was part of their demo fleet, they did all the service and maintenance. They SHOULD make good on this.
 
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