Broken Shock Stud

[cowboyup3371]

First, I haven't searched for the other threads I know are on the forum yet but I wanted to put this up in case those who have experienced this issue can provide their recommendations.

While mounting Charmayne's new shocks onto her bike, we noticed the right side stud had broken off with most of it still in the nut. Although I am already thinking I will need to weld on some all thread, can I just use a standard nut to secure the shock or do I not have enough thread to do so securely?

Busted stud without shock in place



with shock in place



with shock and outside washer

 

[Cipher]

This is a huge safety issue,
Get a new bit welded on cos I thin the current remnant is seriously compromised.
Metal tends not to forgive.

 

[cowboyup3371]

So after reading a few threads, I noticed quite a few said to drill through the stud and insert a new smaller in diameter bolt through it. How hard of metal is that stud and is there any recommendation as to the drill bit type?

 

[Cipher]

SO terribly wrong of you to do a half assed bodge on a critical component.

 

[cowboyup3371]

Cipher, you have been after me for a long time and I have no clue why. I'm repeating what some very respected members of this forum have recommended doing MULTIPLE Times. If you have nothing substantive to add then please back off


And another note, shock studs are not replaceable so putting a new bit on is not possible

 

[hillsy]

I've seen it done on many bikes. An M6 bolt will be strong enough - there's very little side loading on a shock mount like that.

Although, I would probably weld some stock on there and cut a new thread (because I have a welder).

 

[tkent02]

SO terribly wrong of you to do a half assed bodge on a critical component.

How half assed of you to post anything at all without showing the correct way to do it.

 

[Guest]

Why don't you just retap the thread you have?

 

[Guest]

Cut the compromised thread off and smooth off the stub end. Center punch the stub and pilot drill a 3/16 hole as close to center and as straight as you can. Use WD40 as a cutting oil. This will help the tap drill hold size.
If you choose the M6 thread the tap will be M6 x 1 and the drill would be 5mm or a #8.
I would prefer an M8 x 1.25 and that tap drill would be a 6.75 mm or a letter I (eye).
On your tap drill take your time as it will want to dive in.
I'd go at least 15 mm deep. Start the tap straight and back out every half turn or so to break chips.
Do not force the tap because if you break it off in the hole well...then you can weld something (which I wouldn't recommend).
Use plenty of WD40.
IMO that would be your best option for safety.

 

[cowboyup3371]

Why don't you just retap the thread you have?

There's only about two or three threads left before you hit the shoulder where the shock sits.

I've seen it done on many bikes. An M6 bolt will be strong enough - there's very little side loading on a shock mount like that.

Although, I would probably weld some stock on there and cut a new thread (because I have a welder).

Thanks Hillsy. My friend also has a welder and said last night he'd try it but I have to get him more wire first. Hopefully Lowes is open today

 

[cowboyup3371]

Cut the compromised thread off and smooth off the stub end. Center punch the stub and pilot drill a 3/16 hole as close to center and as straight as you can. Use WD40 as a cutting oil. This will help the tap drill hold size.
If you choose the M6 thread the tap will be M6 x 1 and the drill would be 5mm or a #8.
I would prefer an M8 x 1.25 and that tap drill would be a 6.75 mm or a letter I (eye).
On your tap drill take your time as it will want to dive in.
I'd go at least 15 mm deep. Start the tap straight and back out every half turn or so to break chips.
Do not force the tap because if you break it off in the hole well...then you can weld something (which I wouldn't recommend).
Use plenty of WD40.
IMO that would be your best option for safety.

Thank you sir, I'll give that a shot.


I'm glad I checked the forum before I left for Lowes as I didn't see this when I posted my replies to AZR and Hillsy

 

[Dogma]

I'm having trouble understanding how studs get broken there. I can easily imagine stripping one. How did it happen?

 

[cowboyup3371]

I'm having trouble understanding how studs get broken there. I can easily imagine stripping one. How did it happen?

I have my suspicions but am not really sure as I wasn't doing the work - just saw that she had it off.

 

[Mickeymoe]

Sorry to read of your dilema Cowboyup. When I just replaced my tires and had the shocks off, I noticed that my shock stud's threads were pretty buggered up. I cringed at the thought that they might strip or break off but I cut the factory nut to actually thread on. I don't have a lot of confidence that I can do it too many more times without an issue. I was also wondering what one would do if the stud had to be replaced and figured it would be addressed on the forum somewhere. Anyway, the real reason for my post I'd like to get a die and "chase" the threads on the stud and replace the stock chrome nuts. Does anyone know what the bolt/ thread size/ threads per inch the studs are? I'm not that well versed on tap and drill sizes.

THanks, Mark

P.S. Good luck with your drill and tap job.

 

[cowboyup3371]

I measured before I went to get the parts I needed and they were a M10 x 1.50

 

[tatu]

And another note, shock studs are not replaceable so putting a new bit on is not possible

Ahem....

http://www.thegsresources.com/_foru...ock-Mount-Repair&highlight=shock+mount+repair

 

[cowboyup3371]

Ahem....

http://www.thegsresources.com/_foru...ock-Mount-Repair&highlight=shock+mount+repair

Sorry Tatu, I misread your original thread as you used a bolt but see now it's an extra stud. Wish I had one like that and access to a lathe

 

[cowboyup3371]

Ugghhh, I hate my life sometimes. Cut off the old threads, drilled out the hole, and was cutting what I figured would be the last turn when the dang tap broke off inside.

I ended up cutting off the stud and i'm going to now drill through the frame to slide in a M12x1.50x100mm long bolt. If this works then my friend will weld it into place for me.

 

[Guest]

Soooo close.
The bad thing with tapping is that you have all the work done till you hear that snap.
I liked tatu's procedure too.

 

[geol]

The tap is a pain to drill out but you might be able to drill through it with a carbide drill bit. You can get a large enough automotive exhaust manifold stud to do the fix. Most auto parts stores will have 1/2" exhaust manifold studs in stock which is about the same size as an M12 bolt. You can just screw it into the tapped hole and then tack weld it. I would recommend using cutting oil (not WD40) when doing this stuff and to use a carbide tap... not one of those made in China no-names from Harbor Freight. I have give you some free advice on this but I have myself paid for this bit of education. Most taps ARE made in China these days but reputable brands won't snap like the ones that come in the $10 kit from Harbor Freight.