Exhaust Stud Replacement?

[Thumper]

One way to help center a drill bit on uneven broken stud is to use a punch. Take your time getting the hole centered. Punch drill, punch, drill...The punch also has the side effect of loosening the threads in the head. I always get some PB blaster or equivalent on there to soak before starting the process.

Thread size should be the same in the head as on the exposed threads. You can use a nut from holding on the flange to see what the size is. Maybe M8 x 1.25 (post 22 this thread)

[Thumper]

Originally Posted by Ariel Red Hunter

True. His problem is that the big box stores carry the absolute cheapest quality imaginable. And that is where most people in the States go to look...ARH

I think "all-thread" at big box stores is actually zinc. I used 1/4" all-thread to replace battery clamp rods in a tractor. Anything requiring actual torque would fail!

[zero_dgz]

Originally Posted by Thumper

I think "all-thread" at big box stores is actually zinc. I used 1/4" all-thread to replace battery clamp rods in a tractor. Anything requiring actual torque would fail!

They're zinc plated. Definitely steel. Mild steel for sure, but still. A magnet will tell you.


You're right in that a solid zinc piece of allthread wouldn't stand up to... much of anything, really. It'd make a bitchin' high surface area electrode for zinc plating other things, though!

[TominMO]

Is it possible to cut a slot using a diamond cutoff wheel in a Dremel? Then use a flat screwdriver to remove the old stud. Just a thought.

[Chinabike]

found it better just buying a new head

[thederrick106]

I found this reply in another thread:

Originally Posted by Megadan

Since the studs in question are metric (M8 x 1.25) the equivalent of grade 8 (SAE) would be grade 10.9.

On my last Hawk and the current one, I upgraded to stainless steel (A2) studs, washers, and nuts. Much like ARH, I use a double nut (main and locking) to secure the head pipe. I have never had one come loose or back out. The mid pipe mount is also crucial to prevent stud breakage (the one on the frame under the seat area). If that is loose and allows the pipe to vibrate it will put a lot of stress on the studs and increase the chance of, or lead up to, failures. I put two large flat washers on each side of the rubber in order to tighten it down enough without completely destroying the rubber in the process.

http://www.chinariders.net/newreply....reply&p=294479

[Megadan]

Good place to source studs https://www.belmetric.com/m8x125-coa...d-c-9_71_1840/

Just match the length dismensions to what you have.

[TxTaoRider]

I've had pretty good luck using left hand drill bits. The studs will usually come out while drilling into them.

[jatgm12]

Hey so I tried getting them out and just basically got nowhere. Drilled the hole, tried to remove it, didn't work. Tried to drill it out and thread it, also didn't work. I got a new cylinder head. I figured out their m8 x 1.25 studs and got replacements too. Turns out the intake is a different size. Can someone let me know the intake bolt size and thread pitch? Is it m6? Im not sure. I assume it's standardized.

[Thumper]

You can take a guess and buy a couple of metric bolts and see if they fit. Or just break down and buy a thread gauge like this one.
These things are SOOoo useful to have.

[jatgm12]

Originally Posted by Thumper

You can take a guess and buy a couple of metric bolts and see if they fit. Or just break down and buy a thread gauge like this one.
These things are SOOoo useful to have.


Attachment 28923

Dude I didn't know they made that. Nobody tells me these things lol. Do you have a cg250 and happen to know what size the intake stud is though? I kinda wanna just get the metric m6 studs and the gauge and be able to just pop it in, fix this thing and be done. I was hoping someone else could just confirm it's m6 so I don't waste time and money getting the Studs on Amazon.

[Megadan]

Intake bolts are an M6 bolt by 20mm long. I just can't remember the thread pitch with confidence, but I believe it is just a 1.0 ( aka M6x1.0x20 )